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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q


☒			QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended ~~September~~March 3031, ~~2025~~2026


☐			TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from ______ to ______

Commission File No. 1-6571

Merck & Co., Inc.

(Exact name of registrant as specified in its charter)


New Jersey	22-1918501
(State or other jurisdiction of incorporation)	(I.R.S. Employer Identification No.)

126 East Lincoln Avenue
Rahway	New Jersey	07065
(Address of principal executive offices) (zip code)

(Registrant’s telephone number, including area code) (908) 740-4000


			Not Applicable
(Former name, former address and former fiscal year, if changed since last report.)


Securities Registered pursuant to Section 12(b) of the Act:
Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock ($0.50 par value)	MRK	New York Stock Exchange
1.875% Notes due 2026	MRK/26	New York Stock Exchange
3.250% Notes due 2032	MRK/32	New York Stock Exchange
2.500% Notes due 2034	MRK/34	New York Stock Exchange
1.375% Notes due 2036	MRK 36A	New York Stock Exchange
3.500% Notes due 2037	MRK/37	New York Stock Exchange
3.700% Notes due 2044	MRK/44	New York Stock Exchange
3.750% Notes due 2054	MRK/54	New York Stock Exchange

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company.


Large accelerated filer	☒	Accelerated filer	☐

Non-accelerated filer	☐	Smaller reporting company	☐

		Emerging growth company	☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The number of shares of common stock outstanding as of the close of business on ~~October~~April 3130, ~~2025~~2026: 2,~~482~~469,~~022~~824,~~536~~415

Table of Contents

Page No.

PART I

FINANCIAL INFORMATION

Item 1.

Financial Statements

Condensed Consolidated Statement of Income

Condensed Consolidated Statement of Operations

Condensed Consolidated Statement of Comprehensive Income

Condensed Consolidated Statement of Comprehensive (Loss) Income

Condensed Consolidated Balance Sheet

Condensed Consolidated Statement of Cash Flows

Notes to Condensed Consolidated Financial Statements

Item 2.

Management’s Discussion and Analysis of Financial Condition and Results of Operations

3529

Item 3.

Quantitative and Qualitative Disclosures about Market Risk

5042

Item 4.

Controls and Procedures

5042

Cautionary Factors That May Affect Future Results

5142

PART II

OTHER INFORMATION

5143

Item 1.

Legal Proceedings

5143

Item 2.

Unregistered Sales of Equity Securities and Use of Proceeds

5143

Item 5.

Other Information

5143

Item 6.

Exhibits

5244

Signatures

5345

Part I - Financial Information

Item 1. Financial Statements

MERCK & CO., INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENT OF ~~INCOME~~OPERATIONS

(Unaudited, $ in millions except per share amounts)

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
	2025		2024		2025		2024
	2026		2025
Sales	$	1716,~~276~~286	$	1615,~~657~~529	$	~~48,611~~	$	~~48,544~~
Costs, Expenses and Other
Cost of sales	34,~~855~~195		43,~~080~~419		~~10,831~~		~~11,365~~
Selling, general and administrative	2,~~633~~700		2,~~731~~552		~~7,835~~		~~7,952~~
Research and development	412,~~234~~592		53,~~862~~621		~~11,903~~		~~13,354~~
Restructuring costs	47195		5669		~~676~~		~~258~~
Other (income) expense, net	~~(238)~~138		(~~162~~35)		~~(281)~~		~~(151)~~
	10,531		12,567		30,964		32,778
	19,820		9,626
Income Before Taxes	6,745		4,090		17,647		15,766
(Loss) Income Before Taxes	(3,534)		5,903
Taxes on Income	958		929		2,346		2,377
Income Tax Provision	709		818
Net Income	5,787		3,161		15,301		13,389
Net (Loss) Income	(4,243)		5,085
Less: Net Income Attributable to Noncontrolling Interests	2		4		10		15
Less: Net (Loss) Income Attributable to Noncontrolling Interests	(3)		6
Net Income Attributable to Merck & Co., Inc.	$	5,785	$	3,157	$	15,291	$	13,374
Net (Loss) Income Attributable to Merck & Co., Inc.	$	(4,240)	$	5,079
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders	$	2.32	$	1.25	$	6.09	$	5.28
Basic (Loss) Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders	$	(1.72)	$	2.01
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders	$	2.32	$	1.24	$	6.08	$	5.26
(Loss) Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders	$	(1.72)	$	2.01

MERCK & CO., INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE (LOSS) INCOME

(Unaudited, $ in millions)

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
	2025		2024		2025		2024
	2026		2025
Net Income Attributable to Merck & Co., Inc.	$	5,785	$	3,157	$	15,291	$	13,374
Net (Loss) Income Attributable to Merck & Co., Inc.	$	(4,240)	$	5,079
Other Comprehensive Income (Loss) Net of Taxes:
Net unrealized gain (loss) on derivatives, net of reclassifications	~~170~~216		(~~296~~217)		~~(457)~~		~~(99)~~
Benefit plan net gain (loss) and prior service credit (cost), net of amortization	745		(1318)		48		~~(28)~~
Cumulative translation adjustment	~~(25)~~6		~~299~~215		~~152~~		~~(83)~~
	219		(10)		(257)		(210)
	227		(20)
Comprehensive Income Attributable to Merck & Co., Inc.	$	6,004	$	3,147	$	15,034	$	13,164
Comprehensive (Loss) Income Attributable to Merck & Co., Inc.	$	(4,013)	$	5,059

The accompanying notes are an integral part of these condensed consolidated financial statements.

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MERCK & CO., INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEET

(Unaudited, $ in millions except per share amounts)

	September 30, 2025		December 31, 2024
	March 31, 2026		December 31, 2025
Assets
Current Assets
Cash and cash equivalents	$	185,~~169~~327	$	1314,~~242~~565
Short-term investments	45375		~~447~~—
Accounts receivable (net of allowance for doubtful accounts of $93 in 2025 and $89 in 2024)	12,120		10,278
Accounts receivable (net of allowance for doubtful accounts of $103 in 2026 and $97 in 2025)	12,210		11,775
Inventories (excludes inventories of $5,412 in 2025 and $4,193 in 2024classified in Other assets - see Note 6)	6,444		6,109
Inventories (excludes inventories of $6,195 in 2026 and $5,681 in 2025classified in Other assets - see Note 6)	6,479		6,658
Other current assets	10,~~779~~624		810,~~706~~518
Total current assets	4735,~~557~~015		3843,~~782~~516
Investments	1,~~117~~105		~~463~~956
Property, Plant and Equipment, at cost, net of accumulated depreciation of $20,605 in 2025 and $19,155 in 2024	25,639		23,779
Property, Plant and Equipment, at cost, net of accumulated depreciation of $22,288 in 2026 and $21,914 in 2025	25,433		25,316
Goodwill	21,~~587~~581		21,~~668~~579
Other Intangibles, Net	1525,~~313~~745		1626,~~370~~681
Other Assets	1819,~~333~~806		1618,~~044~~818
	$	~~129~~128,~~546~~685	$	~~117~~136,~~106~~866
Liabilities and Equity
Current Liabilities
Loans payable and current portion of long-term debt	$	12,~~405~~444	$	2,~~649~~589
Trade accounts payable	43,~~147~~863		4,~~079~~404
Accrued and other current liabilities	1614,~~186~~549		1514,~~694~~468
Income taxes payable	43,~~848~~946		34,~~914~~726
Dividends payable	2,~~042~~143		2,~~084~~140
Total current liabilities	2826,~~628~~945		28,~~420~~327
Long-Term Debt	3946,~~969~~673		3446,~~462~~750
Deferred Income Taxes	1,~~381~~494		1,~~387~~439
Other Noncurrent Liabilities	7,~~661~~642		67,~~465~~688
Merck & Co., Inc. Stockholders’ Equity
Common stock, $0.50 par valueAuthorized - 6,500,000,000 sharesIssued - 3,577,103,522 shares in 2025 and 2024	1,788		1,788
Common stock, $0.50 par valueAuthorized - 6,500,000,000 sharesIssued - 3,577,103,522 shares in 2026 and 2025	1,788		1,788
Other paid-in capital	4445,~~832~~176		4445,~~704~~029
Retained earnings	7266,~~231~~721		6373,~~069~~075
Accumulated other comprehensive loss	(54,~~202~~060)		(4,~~945~~287)
	113,649		104,616
	109,625		115,605
Less treasury stock, at cost:1,089,754,712 shares in 2025 and 1,049,466,187 shares in 2024	61,799		58,303
Less treasury stock, at cost:1,107,410,143 shares in 2026 and 1,102,476,756 shares in 2025	63,747		62,999
Total Merck & Co., Inc. stockholders’ equity	5145,~~850~~878		4652,~~313~~606
Noncontrolling Interests	5753		5956
Total equity	5145,~~907~~931		4652,~~372~~662
	$	~~129~~128,~~546~~685	$	~~117~~136,~~106~~866

The accompanying notes are an integral part of this condensed consolidated financial statement.

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MERCK & CO., INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS

(Unaudited, $ in millions)

	Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
	2025		2024
	2026		2025
Cash Flows from Operating Activities
Net income	$	15,301	$	13,389
Net (loss) income	$	(4,243)	$	5,085
Adjustments to reconcile net income to net cash provided by operating activities:
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Amortization	~~1,820~~931		~~1,720~~597
Depreciation	~~1,552~~581		~~1,582~~502
Income from investments in equity securities, net	(~~563~~168)		(~~169~~90)
Charges for research and development asset acquisitions	—		2,756
Charge for research and development asset acquisition	8,540		—
Deferred income taxes	(~~846~~315)		(~~633~~186)
Share-based compensation	~~615~~185		~~574~~195
Other	~~393~~20		~~611~~109
Net changes in assets and liabilities	(41,~~657~~613)		(13,~~812~~712)
Net Cash Provided by Operating Activities	133,~~615~~918		182,~~018~~500
Cash Flows from Investing Activities
Capital expenditures	(~~3,079~~991)		(21,~~435~~328)
Purchases of securities and other investments	(~~1,207~~374)		(64595)
Proceeds from sales of securities and other investments	~~1,632~~—		~~370~~456
Acquisition of Eyebiotech Limited, net of cash acquired	—		(1,344)
Acquisition of Cidara Therapeutics, Inc., net of cash acquired	(8,779)		—
Acquisition of Elanco Animal Health Incorporated aqua business	—		(1,301)
Other	(66)		(20)
Acquisition of Harpoon Therapeutics, Inc., net of cash acquired	—		(746)
Net Cash Used in Investing Activities	(10,210)		(1,487)
Acquisition of MK-1045 (formerly CN201) from Curon Pharmaceutical	—		(700)
Other	114		(70)
Net Cash Used in Investing Activities	(2,540)		(6,290)
Cash Flows from Financing Activities
Net change in short-term borrowings	631,061		—
Proceeds from issuance of debt	5,962		3,599
Payments on debt	(1,140)		(2,500)
Payments on debt	(2,501)		(751)
Dividends paid to stockholders	(2,105)		(2,050)
Dividends paid to stockholders	(6,158)		(5,889)
Purchases of treasury stock	(874)		(1,164)
Purchases of treasury stock	(3,832)		(817)
Proceeds from exercise of stock options	157		19
Proceeds from exercise of stock options	45		165
Other	(80)		(60)
Other	(252)		(330)
Net Cash Used in Financing Activities	(2,981)		(5,755)
Net Cash Used in Financing Activities	(6,673)		(4,023)
Effect of Exchange Rate Changes on Cash, Cash Equivalents and Restricted Cash	(19)		156
Effect of Exchange Rate Changes on Cash, Cash Equivalents and Restricted Cash	540		74
Net Decrease in Cash, Cash Equivalents and Restricted Cash	(9,292)		(4,586)
Net Increase in Cash, Cash Equivalents and Restricted Cash	4,942		7,779
Cash, Cash Equivalents and Restricted Cash at Beginning of Year (includes restricted cash of $125 and $76 at January 1, 2026 and 2025, respectively, included in Other current assets)	14,690		13,318
Cash, Cash Equivalents and Restricted Cash at Beginning of Year (includes restricted cash of $76 and $68 at January 1, 2025 and 2024, respectively, included in Other current assets)	13,318		6,909
Cash, Cash Equivalents and Restricted Cash at End of Period (includes restricted cash of $71 and $103 at March 31, 2026 and 2025, respectively, included in Other current assets)	$	5,398	$	8,732
Cash, Cash Equivalents and Restricted Cash at End of Period (includes restricted cash of $91 and $95 at September 30, 2025 and 2024, respectively, included in Other current assets)	$	18,260	$	14,688

The accompanying notes are an integral part of this condensed consolidated financial statement.

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Notes to Condensed Consolidated Financial Statements (unaudited)

1. Basis of Presentation

The accompanying unaudited condensed consolidated financial statements of Merck & Co., Inc. (Merck or the Company) have been prepared pursuant to the rules and regulations for reporting on Form 10-Q. Accordingly, certain information and disclosures required by accounting principles generally accepted in the United States (U.S.) for complete consolidated financial statements are not included herein. These interim statements should be read in conjunction with the audited financial statements and notes thereto included in Merck’s Form 10-K filed on February 2524, ~~2025~~2026.

The results of operations of any interim period are not necessarily indicative of the results of operations for the full year. In the Company’s opinion, all adjustments necessary for a fair statement of these interim statements have been included and are of a normal and recurring nature. Certain reclassifications have been made to prior year amounts to conform to the current year presentation.

Recently Issued Accounting Standards Not Yet Adopted

In ~~December~~November ~~2023~~2024, the Financial Accounting Standards Board (FASB) issued guidance intended to improve ~~the~~financial ~~transparency~~reporting ~~of income tax disclosures~~ by requiring ~~consistent~~entities ~~categories~~to ~~and~~disclose ~~disaggregation~~additional of information inabout ~~the~~specific ~~effective~~expense ~~income~~categories ~~tax~~for ~~rate~~interim ~~reconciliation~~ and ~~income~~annual ~~taxes~~reporting ~~paid disclosures by jurisdiction~~periods. The guidance ~~also~~is ~~includes~~effective ~~other~~for ~~amendments~~2027 toannual ~~improve~~reporting ~~the~~and ~~effectiveness~~2028 ofinterim ~~income~~reporting. ~~tax~~Early ~~disclosures~~adoption byis ~~removing certain previously required disclosures~~permitted. The guidance, iswhich ~~effective~~can ~~for~~be ~~2025~~applied ~~annual~~on ~~reporting~~a ~~and~~prospective or retrospective basis, will result in incremental disclosures within the footnotes to the Company’s financial statements.

In ~~November~~December ~~2024~~2025, the FASB issued guidance ~~intended~~that toincludes ~~improve~~requirements for recognition of government grants in a company’s financial ~~reporting~~statements byas ~~requiring~~well ~~entities~~as todisclosure ~~disclose~~requirements, ~~additional~~including ~~information~~the ~~about~~nature ~~specific~~of ~~expense~~the ~~categories~~government atgrant ~~interim~~received, the accounting policies used to account for the grant, and ~~annual~~significant ~~reporting~~terms ~~periods~~and conditions of the grant. The guidance is effective for ~~2027~~2029 interim and annual reporting ~~and~~on ~~2028~~a ~~interim~~modified ~~reporting~~prospective, modified retrospective or retrospective approach. Early adoption is permitted. ~~The~~as ~~guidance,~~of ~~which~~the ~~can~~beginning beof ~~applied~~an onannual areporting ~~prospective~~period. orThe ~~retrospective~~Company ~~basis,~~is ~~will~~currently ~~result~~evaluating inthe ~~incremental~~impact ~~disclosures~~of ~~within~~adoption ~~the~~on ~~footnotes~~its toconsolidated ~~the Company’s~~ financial statements.

In September 2025, the FASB issued guidance intended to clarify and modernize the accounting for costs related to internal-use software. The guidance removes all references to software development project stages and clarifies the criteria entities should apply to begin capitalizing costs. The guidance is effective for 2028 annual and interim reporting and can be applied on a prospective, retrospective, or modified retrospective basis. Early adoption is permitted. The Company is currently evaluating the impact of adoption on its consolidated financial statements.

2. Acquisitions, Research Collaborations and Licensing Agreements

The Company continues to pursue acquisitions and the establishment of external alliances such as research collaborations and licensing agreements to complement its internal research capabilities. These arrangements often include upfront payments; expense reimbursements or payments to the third party; milestone, royalty or profit share arrangements contingent upon the occurrence of certain future events linked to the success of the asset in development; and can also include option and continuation payments. The Company also reviews its marketed products and pipeline to examine candidates which may provide more value through out-licensing and, as part of its portfolio assessment process, may also divest certain assets. Pro forma financial information for acquired businesses is not presented if the historical financial results of the acquired entity are not significant when compared with the Company’s financial results.

~~2025~~2026 Transactions

In ~~November~~March ~~2025~~2026, Merck ~~reached~~entered aninto a definitive agreement ~~with~~to ~~Dr.~~acquire ~~Falk~~Terns ~~Pharma~~Pharmaceuticals, ~~GmbH~~Inc. (~~Falk~~Terns), toa ~~discontinue~~clinical-stage anoncology ~~existing~~company, ~~contract~~for ~~concerning~~$53 ~~co-development~~per ~~and~~share, cofor a total transaction value of approximately $6.7 billion. Through this acquisition, Merck will acquire Terns’ lead candidate, TERN-~~commercialization~~701, ~~rights~~a novel investigational oral allosteric BCR::ABL1 tyrosine kinase inhibitor (TKI) currently being evaluated in ~~certain~~a ~~territories~~Phase 1/2 trial for ~~MK-8690~~patients ~~(formerly~~with ~~PRA~~Philadelphia chromosome-~~052)~~positive, ~~and~~chronic ~~for~~phase ~~Merck~~chronic tomyeloid ~~assume~~leukemia ~~full~~previously ~~responsibility~~treated ~~for~~with ~~the~~at ~~development~~least ~~program~~one ~~going~~prior ~~forward.~~TKI ~~MK-8690~~and iswho anexperienced ~~investigational~~treatment ~~anti-CD30~~failure, ~~ligand~~suboptimal ~~monoclonal~~response ~~antibody~~or ~~being~~treatment ~~evaluated~~intolerance. The transaction has been approved by ~~the~~both ~~Company~~Merck’s inand anTerns’ ~~early-stage~~Boards ~~clinical~~of ~~trial~~Directors. ~~Under~~The ~~the~~acquisition ~~terms~~is ofsubject ~~the~~to ~~agreement,~~a ~~Merck~~majority ~~and~~of ~~Falk~~Terns’ ~~have~~stockholders ~~discontinued~~tendering their ~~collaboration~~shares ~~based~~in onthe ~~their~~tender ~~existing~~offer ~~co-development~~initiated ~~contract~~by ~~resulting~~Merck in ~~Merck~~April ~~having~~2026. ~~secured~~The ~~global~~consummation ~~rights~~of tothe ~~MK-8690.~~proposed Intransaction ~~exchange,~~is ~~Falk~~also ~~will~~subject ~~receive~~to acustomary ~~$150 million~~closing ~~upfront~~conditions. ~~payment,~~Merck ~~which~~anticipates the ~~Company~~transaction will ~~record~~be accounted for as aan ~~charge~~asset acquisition since TERN-701 is expected to ~~Research~~account ~~and~~for ~~development~~substantially ~~expenses~~all inof the ~~fourth~~fair ~~quarter~~value of ~~2025~~the gross assets to be acquired (excluding cash and deferred income taxes). ~~Falk~~Upon closing of the transaction, which is ~~also~~anticipated ~~eligible~~in May 2026, Merck expects to ~~receive~~record a ~~developmental~~charge ~~milestone~~of ~~payment,~~approximately as$5.8 billion ~~well~~to asResearch ~~tiered~~and ~~low-single-digit~~development ~~royalties~~expenses. onThere ~~sales~~are inno ~~certain~~future ~~territories~~contingent payments associated with the acquisition.

In ~~October~~January ~~2025~~2026, Merck acquired ~~Verona~~Cidara ~~Pharma~~Therapeutics, ~~plc~~Inc. (~~Verona Pharma~~Cidara), a ~~biopharmaceutical~~biotechnology company ~~focused~~developing ondrug-Fc ~~respiratory~~conjugate ~~diseases~~(DFC) therapeutics, for ~~total consideration of approximately~~ $109.52 billion (including $570 million of payments to settle share-based equity awards of which $406 million related to unvested equity awards). ~~Through~~Cidara’s ~~this~~lead ~~acquisition~~DFC candidate, ~~Merck~~MK-1406 ~~acquired Ohtuvayre~~ (~~ensifentrine~~formerly CD388), is a ~~first~~long-inacting antiviral designed to prevent seasonal and pandemic influenza. MK-~~class~~1406 ~~selective~~is ~~dual~~currently ~~inhibitor~~being ofevaluated ~~phosphodiesterases~~in a Phase 3 ~~and~~trial 4among ~~(PDE3~~adult and ~~PDE4),~~adolescent ~~which~~participants ~~was~~who ~~approved~~are inat ~~the~~higher Urisk of developing complications from influenza.S. inThe ~~June~~transaction ~~2024~~was accounted for as an asset acquisition since MK-1406 accounted for substantially all of the ~~maintenance~~fair ~~treatment~~value of ~~chronic~~the ~~obstructive~~gross ~~pulmonary~~assets ~~disease~~acquired (~~COPD~~excluding cash and deferred income taxes). inMerck ~~adult~~recorded ~~patients~~a charge of $9.0 billion to Research and isdevelopment ~~also~~expenses ~~being~~(which ~~evaluated~~primarily represented acquired in-process ~~clinical~~research ~~trials~~and ~~for~~development ~~the~~with ~~treatment~~no ofalternative ~~non-cystic~~future ~~fibrosis~~use), ~~bronchiectasis.~~as ~~The~~well ~~Company~~as isnet assets of $332 million in the ~~process~~first quarter of ~~determining~~2026. ~~the~~Under ~~fair~~a ~~value~~previous oflicense ~~assets~~agreement ~~acquired~~between Cidara and ~~liabilities~~J&J ~~assumed~~Innovative inMedicine ~~this~~(a ~~transaction;~~Johnson ~~however~~& Johnson company, itpreviously ~~expects~~Janssen toPharmaceuticals, ~~capitalize~~Inc.), ~~most~~which ofwas ~~the~~assumed ~~purchase~~by ~~price~~Merck, asJ&J anInnovative ~~intangible~~Medicine ~~asset~~is ~~for~~eligible ~~Ohtuvayre.~~to ~~There~~receive ~~are~~up noto ~~future~~$105 million ~~contingent~~in ~~payments~~regulatory ~~associated~~milestones ~~with~~and ~~the~~up ~~acquisition~~to $455 million in sales-based milestones related to MK-1406.

Also in October 2025, Merck and Blackstone Life Sciences (Blackstone) entered into a funding arrangement under which Blackstone will pay Merck $700 million (which is non-refundable, subject to the termination provisions of the agreement) to

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Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

~~fund~~2025 a portion of the Company’s development costs for MK-2870, sacituzumab tirumotecan (sac-TMT), expected to be incurred throughout 2026. The funding will be recognized as a reduction to Research and development expenses as Merck incurs applicable development costs for the sac-TMT program. Sac-TMT is an investigational trophoblast cell-surface antigen 2 (TROP2)-directed antibody drug conjugate (ADC) being developed as part of an exclusive license and collaboration agreement with Kelun-Biotech that is currently in clinical development for the treatment of a variety of cancers. The agreement between Merck and Kelun-Biotech with respect to sac-TMT is unchanged by the new agreement with Blackstone. Merck will retain decision-making authority and control over the development, manufacturing, and commercial activities relating to sac-TMT provided for in the agreement with Kelun-Biotech, and Blackstone will not receive any rights to sac-TMT. Upon receipt of regulatory approval for an indication in the U.S. for first-line triple-negative-breast cancer (TroFuse-011 trial), Blackstone will be eligible to receive low-to-mid single-digit royalties on net sales of sac-TMT subsequent to such approval across all approved indications in Merck’s marketing territories.Transactions

In ~~July~~October 2025, Merck and Blackstone Life Sciences (Blackstone) entered into a funding arrangement under which Blackstone will pay Merck $700 million in the ~~technology~~fourth ~~transfer~~quarter of 2026 (which is non-refundable, subject to the termination provisions of the agreement) to fund a portion of the Company’s development costs for MK-~~2010~~2870, sacituzumab tirumotecan (LMsac-~~299~~TMT), expected to be incurred throughout 2026. Under the terms of the agreement, Merck recognized $200 million of funding in the first quarter of 2026 as a ~~novel~~reduction ~~investigational~~to ~~PD-1/vascular~~Research ~~endothelial~~and ~~growth~~development ~~factor~~expenses, ~~(VEGF)~~and ~~bispecific~~also ~~antibody~~recognized ~~that~~a ~~was~~corresponding ~~licensed~~receivable from ~~LaNova~~Blackstone, ~~Medicines~~which ~~Ltd~~was ~~(LaNova)~~recorded in ~~2024,~~Other ~~was~~current ~~completed~~assets. ~~Accordingly~~Upon receipt of regulatory approval for an indication in the U.S. for first-line triple-negative-breast cancer (TroFuse-011 trial), ~~Merck~~Blackstone ~~made~~will abe ~~$300~~eligible ~~million~~to ~~payment~~receive low-to-mid ~~LaNova~~single-digit royalties on net sales of sac-TMT subsequent to such approval across all approved indications in Merck’s marketing territories. Sac-TMT is an investigational trophoblast cell-surface antigen 2 (~~which~~TROP2)-directed ~~has~~antibody ~~been~~drug ~~acquired~~conjugate by(ADC) ~~Sino~~being developed as part of an exclusive license and collaboration agreement with Sichuan Kelun-Biotech Biopharmaceutical ~~Limited~~Co., Ltd. (Kelun-Biotech) that ~~was~~is ~~recorded~~currently asin clinical development for the treatment of a ~~charge~~variety of cancers. The agreement between Merck and Kelun-Biotech with respect to ~~Research~~sac-TMT is unchanged by the agreement with Blackstone. Merck retained decision-making authority and control over the development, ~~expenses~~manufacturing, and commercial activities relating to sac-TMT provided for in the ~~third~~agreement ~~quarter~~with Kelun-Biotech, and ~~first~~Blackstone ~~nine~~did ~~months~~not ofreceive ~~2025~~any rights to sac-TMT.

In May 2025, Merck and Jiangsu Hengrui Pharmaceuticals Co., Ltd. (Hengrui Pharma) closed an exclusive license agreement for MK-7262 (HRS-5346), an investigational oral small molecule Lipoprotein(a) inhibitor, which is currently being evaluated in a Phase 2 clinical trial in China. Under the agreement, Hengrui Pharma granted Merck exclusive rights to develop, manufacture and commercialize MK-7262 (HRS-5346) worldwide, excluding the Greater China region. The agreement provided for an upfront payment of $200 million, which was recorded as a charge to Research and development expenses in the first nine months of 2025. Hengrui Pharma is also eligible to receive future contingent developmental milestone payments of up to $92.5 million, regulatory milestone payments of up to $177.5 million, and sales-based milestone payments of up to $1.5 billion, as well as tiered royalties ranging from a mid-single-digit rate to a low-double-digit rate on future net sales of MK-7262 (HRS-5346), if approved.

In March 2025, Merck acquired the Dundalk, Ireland facility of WuXi Vaccines (a wholly owned subsidiary of WuXi Biologics), which was accounted for as an asset acquisition. Merck paid $437 million at closing which, combined with previous consideration transferred under a prior manufacturing arrangement with WuXi Vaccines related to this facility, resulted in $759 million being recorded as assets under construction within Property, Plant and Equipment. There are no future contingent payments associated with the acquisition.

2024 Transactions

In September 2024, Merck acquired MK-1045 (formally CN201), a novel investigational clinical-stage bispecific antibody for the treatment of B-cell associated diseases, from Curon Biopharmaceutical (Curon) for an upfront payment of $700 million. In addition, Curon is eligible to receive future contingent developmental milestone payments of up to $300 million and regulatory milestone payments of up to $300 million. The transaction was accounted for as an asset acquisition. Merck recorded a charge of $750 million (reflecting the upfront payment and other related costs) to Research and development expenses in the third quarter and first nine months of 2024 related to the execution of the transaction. In connection with the agreement, Merck is also obligated to pay a third party future contingent developmental, regulatory and sales-based milestone payments of up to $128 million in the aggregate, as well as tiered royalties ranging from a mid-single-digit rate to a low-double-digit rate on future net sales of MK-1045, if approved.

In July 2024, Merck acquired the aqua business of Elanco Animal Health Incorporated (Elanco aqua business) for total consideration of $1.3 billion. The Elanco aqua business consists of an innovative portfolio of medicines and vaccines, nutritionals and supplements for aquatic species; two related aqua manufacturing facilities in Canada and Vietnam; as well as a research facility in Chile. The acquisition broadens Animal Health’s aqua portfolio with products, such as Clynav, a new generation DNA-based vaccine that protects Atlantic salmon against pancreas disease, and Imvixa, an anti-parasitic sea lice treatment. This acquisition also brings a portfolio of water treatment products for warm water production, complementing Animal Health’s warm water vaccine portfolio. In addition to these products, the DNA-based vaccine technology that is a part of the business has the potential to accelerate the development of novel vaccines to address the unmet needs of the aqua industry. There are no contingent payments associated with the acquisition, which was accounted for as a business combination.

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Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The estimated fair values of assets acquired and liabilities assumed from the Elanco aqua business (inclusive of measurement period adjustments) are as follows:

($ in millions)	July 9, 2024
Inventories	$	65
Property, plant and equipment	66
Product rights - Clynav (useful life 15 years) (1)	340
Other product rights (useful lives 15 years) (1)	291
Deferred tax asset	106
Other assets and liabilities, net	23
Total identifiable net assets	891
Goodwill (2)	412
Consideration transferred	$	1,303

(1) The estimated fair values of Clynav and other product rights were determined using an income approach, specifically the multi-period excess earnings method. The future probability-weighted net cash flows were discounted to present value utilizing a discount rate of 8.5%. Actual cash flows are likely to be different than those assumed.

(2) The goodwill recognized is largely attributable to anticipated synergies expected to arise after the acquisition and was allocated to the Animal Health segment. This amount is expected to be deductible for tax purposes.

Also in July 2024, Merck acquired Eyebiotech Limited (EyeBio), a privately held ophthalmology-focused biotechnology company for $1.2 billion (including payments to settle share-based equity awards) and also incurred $207 million of transaction costs. The acquisition agreement also provides for former EyeBio shareholders to receive contingent developmental milestone payments of up to $1.0 billion (of which $200 million has since been paid associated with the achievement of milestones as noted below), regulatory milestone payments of up to $200 million and sales-based milestone payments of up to $500 million. EyeBio’s development work focused on candidates for the prevention and treatment of vision loss associated with retinal vascular leakage, a known risk factor for retinal diseases. EyeBio’s lead candidate, MK-3000 (formerly EYE103), is an investigational, potentially first-in-class tetravalent, tri-specific antibody that acts as an agonist of the Wingless-related integration site signaling pathway, which is in clinical development for the treatment of diabetic macular edema and neovascular age-related macular degeneration. The transaction was accounted for as an asset acquisition since MK-3000 accounted for substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $21 million, as well as a charge of $1.35 billion to Research and development expenses in the third quarter and first nine months of 2024 related to the acquisition. Additionally, a $100 million developmental milestone was recorded as a charge to Research and development expenses in the third quarter and first nine months of 2024 and an additional $100 million developmental milestone was charged to Research and development expenses in the first nine months of 2025.

In March 2024, Merck acquired Harpoon Therapeutics, Inc. (Harpoon), a clinical-stage immunotherapy company developing a novel class of T-cell engagers designed to harness the power of the body’s immune system to treat patients suffering from cancer and other diseases, for $765 million and also incurred $56 million of transaction costs. Harpoon’s lead candidate, gocatamig (MK-6070, formerly HPN328), is a T-cell engager targeting delta-like ligand 3 (DLL3), an inhibitory canonical Notch ligand that is expressed at high levels in small cell lung cancer and neuroendocrine tumors. The transaction was accounted for as an asset acquisition since gocatamig represented substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $165 million, as well as a charge of $656 million to Research and development expenses in the first nine months of 2024 related to the transaction. There are no future contingent payments associated with the acquisition. In August 2024, Merck and Daiichi Sankyo expanded their existing global co-development and co-commercialization agreement to include gocatamig. See Note 3 for more information on Merck’s collaboration with Daiichi Sankyo.

In February 2024, Merck and Alteogen Inc. (Alteogen) converted their existing non-exclusive license agreement into an exclusive license for the use of Alteogen’s proprietary berahyaluronidase alfa for the formulation of subcutaneous pembrolizumab. Pursuant to the amended agreement, Alteogen is eligible to receive regulatory approval milestone payments of up to $51 million, as well as annual and cumulative sales-based milestone payments of up to $1.0 billion in the aggregate. After the achievement of all sales-based milestones, a 2% royalty on net sales is payable to Alteogen. In September 2025, the U.S. Food and Drug Administration (FDA) approved Keytruda Qlex (pembrolizumab and berahyaluronidase alfa-pmph) injection, which triggered regulatory milestone payments of $25 million in the aggregate from Merck to Alteogen. Additionally, following FDA approval, the Company determined that it was probable that sales of Keytruda Qlex in the future would trigger $680 million of sales-based milestone payments from Merck to Alteogen. Accordingly, in the third quarter of 2025, Merck recorded a $705 million liability for these regulatory and sales-based milestone payments and a corresponding intangible asset related to Keytruda Qlex included in Other Intangibles, Net. The intangible asset will be amortized over its estimated useful life through December 2030. The $25 million of regulatory milestone payments were made in October 2025; the future sales-based milestone payments will be paid upon achievement of the corresponding milestone.

- 8 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

3. Collaborative Arrangements

Merck has entered into collaborative arrangements that provide the Company with varying rights to develop, produce and market products together with its collaborative partners. Both parties in these arrangements are active participants and exposed to significant risks and rewards dependent on the commercial success of the activities of the collaboration. Merck’s more significant collaborative arrangements are discussed below.

AstraZeneca PLC

In 2017, Merck and AstraZeneca PLC (AstraZeneca) entered into a global strategic oncology collaboration to co-develop and co-commercialize AstraZeneca’s Lynparza (olaparib) for multiple cancer types. Independently, Merck and AstraZeneca are developing and commercializing Lynparza in combinations with their respective PD-1 and PD-L1 medicines, Keytruda (pembrolizumab) and Imfinzi. Under the terms of the agreement, AstraZeneca and Merck share the development and commercialization costs for Lynparza monotherapy and non-PD-1/PD-L1 combination therapy opportunities.

Profits from Lynparza product sales generated through monotherapies or combination therapies are shared equally. AstraZeneca is the principal on Lynparza sales transactions. Merck records its share of Lynparza product sales, net of cost of sales and commercialization costs, as alliance revenue, and its share of development costs associated with the collaboration as part of Research and development expenses. Reimbursements received from AstraZeneca for research and development expenses are recognized as reductions to Research and development costs.

The initial collaboration agreement also included the joint development and commercialization of AstraZeneca’s Koselugo (selumetinib) for multiple indications, with revenues, costs and profits being accounted for similar to Lynparza. In August 2025, Merck and AstraZeneca amended the terms of the original collaboration agreement, which resulted in the discontinuation of the revenue and cost sharing provisions of the collaboration and ~~simplified~~the simplification of the governance structure related to Koselugo. In exchange, Merck received a $150 million upfront payment (which was recorded within Sales as alliance revenue) in the third quarter of 2025) and ~~may~~$150 million ~~receive~~in ~~future~~February ~~payments~~2026 (which was recorded within Sales as alliance revenue in the first quarter of 2026). Merck may also receive $150 million in ~~each~~the offirst ~~January~~quarter ~~2026~~of ~~and January~~ 2027, and $100 million in ~~January~~the first quarter of 2028, subject to an annual election by AstraZeneca in January of each year as discussed below. Additionally, the amended agreement ~~provides~~provided for Merck to receive contingent regulatory ~~and sales-based~~ milestone payments, asof ~~well~~up asto ~~mid-single-digit~~$175 million ~~royalties~~in onthe ~~future~~aggregate, ~~net~~all ~~sales.~~of ~~Koselugo~~which ~~received~~were atriggered ~~regulatory~~in ~~approval~~2025 inand ~~August~~recorded ~~2025~~within ~~triggering~~Sales aas alliance revenue. Of these milestone ~~payment~~amounts, ($50 million is due from AstraZeneca in ~~2026)~~the third quarter of 2026, $50 million ~~(which~~is ~~was~~due ~~recorded within Sales as alliance revenue~~ in the third quarter of ~~2025)~~2027, and ~~another~~$75 million ~~regulatory~~is ~~approval~~due in ~~October~~the ~~2025~~third ~~triggering~~quarter anof ~~additional~~2028. ~~milestone~~The ~~payment~~Company ~~(due~~is ~~from~~also ~~AstraZeneca~~receiving inmid-single-digit ~~2027)~~royalties ofon ~~$50 million~~net sales (which ~~will~~are beincluded ~~recorded~~ within Sales as alliance revenue ~~in the fourth quarter of 2025~~). Merck remains eligible to receive future contingent payments for the achievement of ~~regulatory milestones of up to $75 million and~~ sales-based milestones of up to $235 million. AstraZeneca has the option in January 2027 or January 2028 to revert back to the income and cost sharing terms of the original agreement (in which case any future annual, contingent milestone, and royalty payments referenced above would no longer be due) although Merck would retain any payments made by AstraZeneca prior to the exercise of that option and any amounts due from AstraZeneca would remain payable to Merck.

As part of the initial collaboration agreement, Merck made an upfront payment to AstraZeneca and also made payments over a multi-year period for certain license options. In addition, the initial collaboration agreement provided for contingent payments from Merck to AstraZeneca related to the successful achievement of sales-based and regulatory milestones. In the first quarter of 2025, Merck made sales-based milestone payments aggregating $700 million (related to the original collaboration agreement) to AstraZeneca of which $600 million related to Lynparza and $100 million related to Koselugo (both of which had been previously accrued for). Potential future sales-based milestone payments of $2.0 billion have not yet

~~In the first nine months of 2025, Merck made sales~~-~~based~~ ~~milestone~~7 payments aggregating $700 million (related to the original collaboration agreement) to AstraZeneca of which $600 million related to Lynparza and $100 million related to Koselugo (both of which had been previously accrued for). Potential future sales-based milestone payments of $2.0 billion have not yet been accrued as they are not deemed by the Company to be probable at this time. Lynparza received a regulatory approval triggering a capitalized milestone payment from Merck to AstraZeneca of $245 million in the first nine months of 2024 (which had been previously accrued for). The partners have agreed that no future regulatory milestone payments from Merck to AstraZeneca are likely.

The intangible asset balances related to Lynparza and Koselugo (which reflect the capitalized sales-based and regulatory milestone payments attributed to each product) were $926 million and $41 million, respectively, at September 30, 2025 and are included in Other Intangibles, Net. The assets are being amortized over their estimated useful lives (through 2028 for Lynparza and through 2029 for Koselugo) as supported by projected future cash flows, subject to impairment testing.

- 9 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

been accrued as they are not deemed by the Company to be probable at this time. The partners have agreed that no future regulatory milestone payments from Merck to AstraZeneca are likely.

The intangible asset balances related to Lynparza and Koselugo (which reflect the capitalized sales-based and regulatory milestone payments attributed to each product) were $762 million and $36 million, respectively, at March 31, 2026 and are included in Other Intangibles, Net. The assets are being amortized over their estimated useful lives (through 2028 for Lynparza and through 2029 for Koselugo) as supported by projected future cash flows, subject to impairment testing.

Summarized financial information related to this collaboration is as follows:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Alliance revenue - Lynparza	$	~~379~~341	$	~~337~~312	$	~~1,061~~	$	~~947~~
Alliance revenue - Koselugo (1)	~~214~~161		3944		~~301~~		~~114~~
Total alliance revenue	$	~~593~~502	$	~~376~~356	$	~~1,362~~	$	~~1,061~~
Cost of sales (2)	84		8283		~~253~~		~~245~~
Selling, general and administrative	3124		3932		~~103~~		~~121~~
Research and development	35		1912		31		57
($ in millions)	March 31, 2026		December 31, 2025		~~September 30, 2025~~		~~December 31, 2024~~
Receivables from AstraZeneca included in Other current assets (3)	$	401	$	451	$	~~436~~	$	~~424~~
Payables to AstraZeneca included in Accrued and other current liabilities (4)					4		713
Receivables from AstraZeneca included in Other assets (3)	125		125
Payables to AstraZeneca included in Accrued and other current liabilities	12		6

(1) ~~Amounts~~Amount in ~~2025 include~~ the ~~$150 million~~first ~~upfront~~quarter ~~payment~~of ~~and~~2026 includes $50150 million ~~regulatory~~related ~~milestone~~to ~~triggered in~~ the ~~third~~amendment ~~quarter as a result~~ of the ~~amendment to the~~ collaboration agreement noted above.

(2) Represents amortization of capitalized milestone payments.

(3) ~~Balance~~Includes ~~at September 30, 2025 includes a~~ milestone ~~receivable~~receivables.

(4) Balance at December 31, 2024 includes accrued milestone payments.

Eisai Co., Ltd.

In 2018, Merck and Eisai Co., Ltd. (Eisai) announced a strategic collaboration for the worldwide co-development and co-commercialization of Lenvima (lenvatinib), an orally available ~~tyrosine~~TKI ~~kinase inhibitor~~ discovered by Eisai. Under the agreement, Merck and Eisai are developing and commercializing Lenvima jointly, both as monotherapy and in combination with Keytruda. Eisai records Lenvima product sales globally (Eisai is the principal on Lenvima sales transactions) and Merck and Eisai share applicable profits equally. Merck records its share of Lenvima product sales, net of cost of sales and commercialization costs, as alliance revenue. Expenses incurred during co-development are shared by the two companies in accordance with the collaboration agreement and reflected in Research and development expenses. Certain expenses incurred solely by Merck or Eisai are not shareable under the collaboration agreement, including costs incurred in excess of agreed upon caps, and costs related to certain combination studies of Keytruda and Lenvima, as well as Welireg (belzutifan) and Lenvima.

Under the agreement, Merck made an upfront payment to Eisai and also made payments over a multi-year period for certain option rights. In addition, the agreement provides for contingent payments from Merck to Eisai related to the successful achievement of sales-based and regulatory milestones. Potential future sales-based milestone payments of $2.3 billion have not yet been accrued as they are not deemed by the Company to be probable at this time. There are no regulatory milestone payments remaining under the agreement.

InThe ~~the~~intangible ~~first~~asset ~~nine~~balance ~~months~~related ofto ~~2024,~~Lenvima ~~Merck~~(which ~~made~~includes acapitalized ~~$125 million~~ sales-based ~~milestone~~and ~~payment~~regulatory tomilestone ~~Eisai~~payments) ~~(which~~was ~~had~~$188 ~~been~~million ~~previously~~at ~~accrued~~March 31, ~~for).~~2026 ~~Potential~~and ~~future~~is ~~sales-based~~included ~~milestone~~in ~~payments~~Other ofIntangibles, $2Net.3 ~~billion~~The ~~have~~amount ~~not~~is ~~yet~~being ~~been~~amortized ~~accrued~~over asits ~~they~~estimated ~~are~~useful ~~not~~life ~~deemed~~through by2029 ~~the~~as ~~Company~~supported toby beprojected ~~probable~~future atcash ~~this~~flows, ~~time.~~subject ~~There~~to ~~are~~impairment ~~no regulatory milestone payments remaining under the agreement~~testing.

The intangible asset balance related to Lenvima (which includes capitalized sales-based and regulatory milestone payments) was $261 million at September 30, 2025 and is included in Other Intangibles, Net. The amount is being amortized over its estimated useful life through 2026 as supported by projected future cash flows, subject to impairment testing.

Summarized financial information related to this collaboration is as follows:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Alliance revenue - Lenvima	$	~~258~~256	$	~~251~~258	$	~~781~~	$	~~755~~
Cost of sales (1)	6013		60		~~181~~		~~181~~
Selling, general and administrative	3327		4031		99		~~120~~
Research and development	2		45		10		18
($ in millions)	March 31, 2026		December 31, 2025		~~September 30, 2025~~		~~December 31, 2024~~
Receivables from Eisai included in Other current assets	$	252	$	271	$	~~258~~	$	~~257~~

(1) Represents amortization of capitalized milestone payments.

~~Bayer~~- AG8 -

In 2014, the Company entered into a worldwide clinical development collaboration with Bayer AG (Bayer) to market and develop soluble guanylate cyclase (sGC) modulators including Bayer’s Adempas (riociguat) and Verquvo (vericiguat). The two companies have implemented a joint development and commercialization strategy. Under the agreement, Bayer

- 10 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

~~commercializes Adempas in the Americas, while Merck commercializes in the rest of the world. For Verquvo, Merck commercializes in the U.S. and~~ Bayer commercializes in the rest of the world. Both companies share in development costs and profits on sales. Merck records sales of Adempas and Verquvo in its marketing territories, as well as alliance revenue. Alliance revenue represents Merck’s share of profits from sales of Adempas and Verquvo in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs. Cost of sales includes Bayer’s share of profits from sales in Merck’s marketing territories.AG

In ~~addition~~2014, the Company entered into a worldwide clinical development collaboration with Bayer AG (Bayer) to market and develop soluble guanylate cyclase (sGC) modulators including Bayer’s Adempas (riociguat) and Verquvo (vericiguat). The two companies have implemented a joint development and commercialization strategy. Under the agreement, Bayer commercializes Adempas in the Americas, while Merck commercializes in the rest of the world. For Verquvo, Merck commercializes in the U.S. and Bayer commercializes in the rest of the world. Both companies share in development costs and profits on sales. Merck records sales of Adempas and Verquvo in its marketing territories, as well as alliance revenue. Alliance revenue represents Merck’s share of profits from sales of Adempas and Verquvo in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs. Cost of sales includes Bayer’s share of profits from sales in Merck’s marketing territories. The agreement provided for contingent payments from Merck to Bayer related to the successful achievement of sales-based milestones. There are no ~~sales-based~~such ~~milestone~~ payments remaining under this collaboration.

The intangible asset balances related to Adempas (which includes the acquired intangible asset balance, as well as capitalized sales-based milestone payments attributed to Adempas) and Verquvo (which reflects the portion of the final sales-based milestone payment that was attributed to Verquvo) were $~~312~~239 million and $4137 million, respectively, at ~~September~~March 3031, ~~2025~~2026 and are included in Other Intangibles, Net. The assets are being amortized over their estimated useful lives (through 2027 for Adempas and through 2031 for Verquvo) as supported by projected future cash flows, subject to impairment testing.

Summarized financial information related to this collaboration is as follows:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Alliance revenue - Adempas/Verquvo	$	~~112~~109	$	~~102~~106	$	~~340~~	$	~~306~~
Net sales of Adempas recorded by Merck	8278		7268		~~229~~		~~214~~
Net sales of Verquvo recorded by Merck	129		119		33		25
Total sales	$	~~206~~196	$	~~185~~183	$	~~602~~	$	~~545~~
Cost of sales (1)	7167		5958		~~190~~		~~182~~
Selling, general and administrative	2212		29		80		88
Research and development	1117		2724		55		82
($ in millions)	March 31, 2026		December 31, 2025		~~September 30, 2025~~		~~December 31, 2024~~
Receivables from Bayer included in Other current assets	$	162	$	167	$	~~168~~	$	~~160~~
Payables to Bayer included in Accrued and other current liabilities	87		81		93		82

(1) Includes amortization of intangible assets, cost of products sold by Merck, as well as Bayer’s share of profits from sales in Merck’s marketing territories.

Ridgeback Biotherapeutics LP

In 2020, Merck and Ridgeback Biotherapeutics LP (Ridgeback), a closely held biotechnology company, entered into a collaboration agreement to develop Lagevrio (molnupiravir), an investigational orally available antiviral candidate for the treatment of patients with COVID-19. Merck gained exclusive worldwide rights to develop and commercialize Lagevrio and related molecules. Following initial authorizations in certain markets in 2021, Lagevrio has since received multiple additional authorizations.

Under the terms of the agreement, Ridgeback received an upfront payment and is eligible to receive future contingent payments dependent upon the achievement of certain developmental and regulatory approval milestones. The agreement also provides for Merck to reimburse Ridgeback for a portion of certain third-party contingent milestone payments and royalties on net sales, which is part of the profit-sharing calculation. Merck is the principal on sales transactions, recognizing sales and related costs, with profit-sharing amounts recorded within Cost of sales. Profits from the collaboration are split equally between the partners. Reimbursements from Ridgeback for its share of research and development costs (deducted from Ridgeback’s share of profits) are reflected as decreases to Research and development expenses.

Summarized financial information related to this collaboration is as follows:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Net sales of Lagevrio recorded by Merck	$	~~138~~28	$	~~383~~102	$	~~323~~	$	~~843~~
Cost of sales (1)	8154		~~204~~53		~~178~~		~~491~~
Selling, general and administrative	11		1113		39		43
Research and development	115		58		25		7
($ in millions)					September 30, 2025		December 31, 2024
Payables to Ridgeback included in Accrued and other current liabilities (2)					$	49	$	68

(1) Includes cost of products sold by Merck, Ridgeback’s share of profits, royalty expense, amortization of capitalized milestone payments and inventory reserves.

~~(2) Includes~~- ~~accrued~~9 ~~royalties.~~-

- 11 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Daiichi Sankyo

In 2023, Merck and Daiichi Sankyo entered into a global development and commercialization agreement for three of Daiichi Sankyo’s DXd ADC candidates: patritumab deruxtecan (~~HER3-DXd) (~~MK-1022), ifinatamab deruxtecan (~~I-DXd) (~~MK-2400) and raludotatug deruxtecan (~~R-DXd) (~~MK-5909). All three potentially first-in-class DXd ADCs are in various stages of clinical development for the treatment of multiple solid tumors both as monotherapy and/or in combination with other treatments. The companies will jointly develop and potentially commercialize these ADC candidates worldwide, except in Japan where Daiichi Sankyo will maintain exclusive rights. Daiichi Sankyo will be solely responsible for manufacturing and supply.

Under the terms of the agreement, Merck made payments to Daiichi Sankyo totaling $4.0 billion in 2023. These payments included $1.0 billion ($500 million each for patritumab deruxtecan and ifinatamab deruxtecan), which may be refundable on a pro-rated basis in the event of early termination of development with respect to either program. In addition, the agreement provided for a continuation payment of $750 million related to patritumab deruxtecan (which Merck paid in October 2024) and a continuation payment of $750 million related to raludotatug deruxtecan (which Merck paid in October 2025). The agreement also provides for contingent payments from Merck to Daiichi Sankyo of up to an additional $5.5 billion for each DXd ADC upon the successful achievement of certain sales-based milestones. In conjunction with this transaction, Merck recorded an aggregate pretax charge of $5.5 billion to Research and development expenses in 2023 for the $4.0 billion of upfront payments and the $1.5 billion of continuation payments.

Merck and Daiichi Sankyo equally share research and development costs, except for raludotatug deruxtecan, where Merck is responsible for 75% of the first $2.0 billion of research and development expenses. Merck includes its share of development costs associated with the collaboration as part of Research and development expenses. Following regulatory approval, Daiichi Sankyo will generally record sales worldwide (Daiichi Sankyo will be the principal on sales transactions) and the companies will equally share expenses as well as profits worldwide except for Japan where Daiichi Sankyo retains exclusive rights and Merck will receive a 5% sales-based royalty. Merck will record its share of product sales, net of cost of sales and commercialization costs, as alliance revenue.

In ~~August~~ 2024, Merck and Daiichi Sankyo expanded their agreement to include gocatamig (MK-6070), an investigational DLL3 targeting T-cell engager, which Merck obtained through its acquisition of Harpoon ~~(see~~Therapeutics, ~~Note 2)~~Inc. The companies are planning to evaluate gocatamig in combination with ifinatamab deruxtecan in certain patients with small cell lung cancer, as well as other potential combinations. Merck received an upfront cash payment of $170 million from Daiichi Sankyo (recorded within Other (income) expense, net) and has also satisfied a contingent quid obligation from the original collaboration agreement. The companies will jointly develop and commercialize gocatamig worldwide and share research and development costs, as well as commercialization expenses. Research and development expenses related to gocatamig in combination with ifinatamab deruxtecan will be shared in a manner consistent with the original agreement for ifinatamab deruxtecan. Merck will be solely responsible for manufacturing and supply of gocatamig. If approved, Merck will generally record sales for gocatamig worldwide (Merck will be the principal on sales transactions) and the companies will equally share expenses as well as profits worldwide, except for Japan where Merck retains exclusive rights and Daiichi Sankyo will receive a 5% sales-based royalty.

Summarized financial information related to this collaboration is as follows:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Cost of sales (1)	$	67	$	—	$	67	$	—
Selling, general and administrative	$	12	$	9
Selling, general and administrative	8		5		21		21
Research and development	160		128
Research and development	110		94		379		227
($ in millions)	March 31, 2026		December 31, 2025
($ in millions)					September 30, 2025		December 31, 2024
Receivables from Daiichi Sankyo included in Other current assets	$	22	$	15
Receivables from Daiichi Sankyo included in Other current assets					$	17	$	8
Payables to Daiichi Sankyo included in Accrued and other current liabilities	85		113
Payables to Daiichi Sankyo included in Accrued and other current liabilities (2)					869		817

(1) Represents Merck’s share of certain inventory-related costs.

(2) Includes accrued continuation payment.

Moderna, Inc.

In 2022, Merck exercised its option to jointly develop and commercialize intismeran autogene (V940/mRNA-4157), an investigational individualized neoantigen therapy, pursuant to the terms of an existing collaboration and license agreement with Moderna, Inc. (Moderna). Intismeran autogene is currently being evaluated in combination with Keytruda in multiple clinical trials. Merck and Moderna share costs and will share any profits equally under this worldwide collaboration. Merck records its share of development costs associated with the collaboration as part of Research and development expenses. Any reimbursements received from Moderna for research and development expenses are recognized as reductions to Research and development costs. Merck has also capitalized a net $~~235~~230 million of shared facility costs at ~~September~~March 3031, ~~2025~~2026, primarily reflected within Other Assets. These costs are amortized over the assets’ estimated useful lives.

- 1210 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Summarized financial information related to this collaboration is as follows:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Selling, general and administrative	$	78	$	56	$	19	$	11
Research and development (1)	9690		9386		~~272~~		~~255~~
($ in millions)	March 31, 2026		December 31, 2025		~~September 30, 2025~~		~~December 31, 2024~~
Payables to Moderna included in Accrued and other current liabilities					$	13	$	57
Receivables from Moderna included in Other current assets	$	4	$	—
Payables to Moderna included in Accrued and other current liabilities	—		13

(1) Includes amortization of shared facility costs.

Bristol-Myers Squibb Company

Reblozyl (luspatercept-aamt) is a first-in-class erythroid maturation recombinant fusion protein that is being commercialized through a global collaboration with Bristol-Myers Squibb Company (BMS). Reblozyl is approved in the U.S., Europe and certain other markets for the treatment of anemia in certain rare blood disorders and is also being evaluated for additional indications for hematology therapies. BMS is the principal on sales transactions for Reblozyl~~; however, Merck co-promotes Reblozyl (and may co-promote any future products approved under this collaboration) in North America, which is reimbursed by BMS~~. Merck receives tiered royalties ranging from 20% to 24% based on sales levels. This royalty will be reduced by 50% upon the earlier of patent expiry or generic entry on an indication-by-indication basis in each market. Additionally, Merck is eligible to receive future contingent sales-based milestone payments of up to $80 million. Alliance revenue related to this collaboration, consisting of royalties (recorded within Sales), was $~~136~~148 million and $~~361~~119 million in the ~~third~~first quarter ~~and first nine months~~ of ~~2025,~~2026 ~~respectively, compared with $100 million~~ and ~~$261 million in the third quarter and first nine months of 2024~~2025, respectively.

4. Restructuring

In July 2025, the Company approved a ~~new~~ restructuring program (2025 Restructuring Program) designed to position the Company for its next chapter of growth and to successfully advance its pipeline and launch new products across multiple therapeutic areas. As part of this program, the Company expects to eliminate certain positions in sales and administrative organizations, as well as research and development. The Company will, however, continue to hire employees into new roles across all strategic growth areas of the business. In addition, the Company will reduce its global real estate footprint and continue to optimize its manufacturing network, aligning the geography of its global manufacturing footprint to its customers and reflecting changes in the Company’s business. Most actions contemplated under the 2025 Restructuring Program are expected to be largely completed by the end of 2027, with the exception of certain manufacturing actions, which are expected to be substantially completed by the end of 2029. The cumulative pretax costs to be incurred by the Company to implement the program are estimated to be approximately $3.0 billion, of which approximately 60% will be cash, relating primarily to employee separation expense and contractual termination costs. The remainder of the costs will be non-cash, relating primarily to the accelerated depreciation of facilities. The Company recorded total pretax costs of $~~302~~318 million ~~and $951 million~~ in the ~~third~~first quarter ~~and~~of ~~first~~2026 ~~nine~~related ~~months~~to ofthe 2025, ~~respectively,~~Restructuring ~~related~~Program. toSince inception of the 2025 Restructuring Program through March 31, 2026, Merck has incurred total cumulative pretax costs of $2.3 billion.

In January 2024, the Company approved a restructuring program (2024 Restructuring Program) intended to continue the optimization of the Company’s Human Health global manufacturing network as the future pipeline shifts to new modalities and also optimize the Animal Health global manufacturing network to improve supply reliability and increase efficiency. The actions contemplated under the 2024 Restructuring Program are expected to be substantially completed by the end of 2031, with the cumulative pretax costs to be incurred by the Company to implement the program estimated to be approximately $4.0 billion. Approximately 6050% of the cumulative pretax costs will be non-cash, relating primarily to the accelerated depreciation of facilities to be closed or divested. The remainder of the costs will result in cash outlays, relating primarily to facility shut-down costs. The Company recorded total pretax costs of $88148 million and $~~279~~105 million in the ~~third~~first quarter of ~~2025~~2026 and ~~2024, respectively, and $323 million and $701 million in the first nine months of~~ 2025 ~~and 2024~~, respectively, related to the 2024 Restructuring Program. Since inception of the 2024 Restructuring Program through ~~September~~March 3031, ~~2025~~2026, Merck has incurred total cumulative pretax costs of $1.48 billion.

For segment reporting, restructuring charges are unallocated expenses.

- 1311 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The following tables summarize the charges related to restructuring program activities by type of cost:

	Three Months Ended September 30, 2025								Nine Months Ended September 30, 2025
	Three Months Ended March 31, 2026
($ in millions)	Accelerated Depreciation		Separation Costs		Other Exit Costs		Total		~~AcceleratedDepreciation~~		~~Separation Costs~~		~~Other Exit Costs~~		~~Total~~
2025 Restructuring Program
Cost of sales	$	—12	$	—	$	72132	$	72144	$	—	$	—	$	~~172~~	$	~~172~~
Research and development	—		—		~~233~~34		~~233~~34		—		—		~~286~~		~~286~~
Restructuring costs	—		—123		~~(3)~~17		~~(3)~~140		—		~~481~~		12		~~493~~
	—		—		302		302		—		481		470		951
	12		123		183		318
2024 Restructuring Program
Cost of sales	5696		—		(183)		3893		~~152~~		—		~~(13)~~		~~139~~
Selling, general and administrative	—		—		—		—		—		—		1		1
Restructuring costs	—		—		55		55
Restructuring costs	—		6		44		50		—		13		170		183
	96		—		52		148
	56		6		26		88		152		13		158		323
	$	108	$	123	$	235	$	466
	$	56	$	6	$	328	$	390	$	152	$	494	$	628	$	1,274

	Three Months Ended September 30, 2024								Nine Months Ended September 30, 2024
	Three Months Ended March 31, 2025
($ in millions)	Accelerated Depreciation		Separation Costs		Other Exit Costs		Total		~~AcceleratedDepreciation~~		~~Separation Costs~~		~~Other Exit Costs~~		~~Total~~
2024 Restructuring Program
Cost of sales	$	4041	$	—	$	~~152~~(5)	$	~~192~~36	$	~~171~~	$	—	$	~~203~~	$	~~374~~
Selling, general and administrative	—		—		31		31		—		—		67		67
Restructuring costs	—		1		68		69
Research and development	—		—		—		—		—		—		2		2
	$	41	$	1	$	63	$	105
Restructuring costs	—		11		45		56		—		122		136		258
	$	40	$	11	$	228	$	279	$	171	$	122	$	408	$	701

Accelerated depreciation costs primarily relate to manufacturing, research and administrative facilities to be fully or partially closed or divested and equipment to be disposed of as part of the programs. Accelerated depreciation costs represent the difference between the depreciation expense to be recognized over the revised useful life of the asset, based upon the anticipated date the site will be closed or divested or the equipment disposed of, and depreciation expense as determined utilizing the useful life prior to the restructuring actions. All the sites will continue to operate up through the respective closure dates and, since future undiscounted cash flows are sufficient to recover the respective book values, Merck is recording accelerated depreciation over the revised useful life of the site assets. Anticipated site closure dates, particularly related to manufacturing locations, have been and may continue to be adjusted to reflect changes resulting from regulatory or other factors.

Separation costs are associated with actual headcount reductions, as well as involuntary headcount reductions which were probable and could be reasonably estimated.

Other exit costs in ~~2025~~2026 and ~~2024~~2025 include asset impairment, facility shut-down, contractual termination, and other related costs, as well as pretax gains and losses resulting from the sales of facilities and related assets. Additionally, other activity includes certain employee-related costs associated with pension and other postretirement benefit plans (see Note 10) and share-based compensation.

The following table summarizes the charges and spending related to restructuring program activities for the ~~nine~~three months ended ~~September~~March 3031, ~~2025~~2026:

($ in millions)	Accelerated Depreciation		SeparationCosts		Other Exit Costs		Total
2025 Restructuring Program
Restructuring reserves January 1, 2025	$	—	$	—	$	—	$	—
Restructuring reserves January 1, 2026	$	—	$	502	$	288	$	790
Expenses	—12		~~481~~123		~~470~~183		~~951~~318
(Payments) receipts, net	—		(7156)		(2166)		(9322)
Non-cash activity	—(12)		—(9)		(81117)		(81138)
Restructuring reserves September 30, 2025	$	—	$	474	$	387	$	861
Restructuring reserves March 31, 2026	$	—	$	460	$	188	$	648
2024 Restructuring Program
Restructuring reserves January 1, 2025	$	—	$	564	$	—	$	564
Restructuring reserves January 1, 2026	$	—	$	506	$	—	$	506
Expenses	~~152~~96		13—		~~158~~52		~~323~~148
(Payments) receipts, net	—		(7870)		(~~161~~53)		(~~239~~123)
Non-cash activity	(~~152~~96)		—12		31		(~~149~~83)
Restructuring reserves September 30, 2025	$	—	$	499	$	—	$	499
Restructuring reserves March 31, 2026	$	—	$	448	$	—	$	448

- 1412 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

5. Financial Instruments

Derivative Instruments and Hedging Activities

The Company manages the impact of foreign exchange rate movements and interest rate movements on its earnings, cash flows and fair values of assets and liabilities through operational means and through the use of various financial instruments, including derivative instruments.

A significant portion of the Company’s revenues and earnings in foreign affiliates is exposed to changes in foreign exchange rates. The objectives of and accounting related to the Company’s foreign currency risk management program, as well as its interest rate risk management activities are discussed below.

Foreign Currency Risk Management

The Company has established revenue hedging, balance sheet risk management and net investment hedging programs to protect against volatility of future foreign currency cash flows and changes in fair value caused by changes in foreign exchange rates.

The objective of the revenue hedging program is to reduce the variability caused by changes in foreign exchange rates that would affect the U.S. dollar value of future cash flows derived from foreign currency denominated sales, primarily the euro, Japanese yen and Chinese renminbi. To achieve this objective, the Company will hedge a portion of its forecasted foreign currency denominated third-party and intercompany distributor entity sales (forecasted sales) that are expected to occur over its planning cycle, typically no more than two years into the future. The Company will layer in hedges over time, increasing the portion of forecasted sales hedged as it gets closer to the expected date of the forecasted sales. The portion of forecasted sales hedged is based on assessments of cost-benefit profiles that consider natural offsetting exposures, revenue and foreign exchange rate volatilities and correlations, and the cost of hedging instruments. The Company manages its anticipated transaction exposure principally with purchased local currency put options, forward contracts, and purchased collar options.

The fair values of these derivative contracts are recorded as either assets (gain positions) or liabilities (loss positions) in the Condensed Consolidated Balance Sheet. Changes in the fair value of derivative contracts are recorded each period in either current earnings or Other comprehensive income (OCI), depending on whether the derivative is designated as part of a hedge transaction and, if so, the type of hedge transaction. For derivatives that are designated as cash flow hedges, the unrealized gains or losses on these contracts are recorded in Accumulated Other Comprehensive Loss (AOCL) and reclassified into Sales when the hedged anticipated revenue is recognized. The amount reclassified into earnings as a result of the discontinuation of cash flow hedges because it was no longer deemed probable the forecasted hedged transactions would occur was not material for the ~~third~~first quarter ~~or first nine months~~ of either ~~2025~~2026 or ~~2024~~2025. For those derivatives which are not designated as cash flow hedges, but serve as economic hedges of forecasted sales, unrealized gains or losses are recorded in Sales each period. The cash flows from both designated and non-designated contracts are reported as operating activities in the Condensed Consolidated Statement of Cash Flows. The Company does not enter into derivatives for trading or speculative purposes.

The Company manages operating activities and net asset positions at each local subsidiary in order to mitigate the effects of foreign exchange on monetary assets and liabilities. Monetary assets and liabilities denominated in a currency other than the functional currency of a given subsidiary are remeasured at spot rates in effect on the balance sheet date with the effects of changes in spot rates reported in Other (income) expense, net. The Company also uses a balance sheet risk management program to mitigate the exposure of such assets and liabilities from the effects of volatility in foreign exchange. Merck principally utilizes forward exchange contracts to offset the effects of foreign exchange on exposures when it is deemed economical to do so based on a cost-benefit analysis that considers the magnitude of the exposure, the volatility of the foreign exchange rate and the cost of the hedging instrument (primarily the euro, Swiss franc, Japanese yen, and Chinese renminbi). The forward contracts are not designated as hedges and are marked to market through Other (income) expense, net. Accordingly, fair value changes in the forward contracts help mitigate the changes in the value of the remeasured assets and liabilities attributable to changes in foreign currency exchange rates, except to the extent of the spot-forward differences. These differences are not significant due to the short-term nature of the contracts, which typically have average maturities at inception of less than six months. The cash flows from these contracts are reported as operating activities in the Condensed Consolidated Statement of Cash Flows.

The Company also uses forward exchange contracts to hedge a portion of its net investment in foreign operations against movements in foreign exchange rates. The forward contracts are designated as hedges of the net investment in a foreign operation. The unrealized gains or losses on these contracts are recorded in foreign currency translation adjustment within OCI and remain in AOCL until either the sale or complete or substantially complete liquidation of the subsidiary. The Company excludes certain portions of the change in fair value of its derivative instruments from the assessment of hedge effectiveness (excluded components). Changes in fair value of the excluded components are recognized in OCI. The Company recognizes in earnings the initial value of the excluded components on a straight-line basis over the life of the derivative instrument, rather than using the mark-to-market approach. The cash flows from these contracts are reported as investing activities in the Condensed Consolidated Statement of Cash Flows.

Foreign exchange risk is also managed through the use of foreign currency debt. Certain of the Company’s senior unsecured euro-denominated notes have been designated as, and are effective as, economic hedges of the net investment in a foreign operation. Accordingly, foreign currency transaction gains or losses due to spot rate fluctuations on the euro-denominated debt instruments are included in foreign currency translation adjustment within OCI.

- 1513 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The effects of the Company’s net investment hedges on OCI and the Condensed Consolidated Statement of Income are shown below:

	Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income (1)				Amount of Pretax Gain Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing				~~Amount of Pretax Gain Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing~~
	Three Months Ended September 30,				Nine Months Ended September 30,				Three Months Ended September 30,				Nine Months Ended September 30,
	Three Months Ended March 31,						Three Months Ended March 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~		~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Net Investment Hedging Relationships
Foreign exchange contracts	$	(2015)	$	127	$	45	$	4	$	(34)	$	—(3)	$	~~(11)~~	$	~~(2)~~
Euro-denominated notes	(1137)		~~169~~130		~~540~~		73		—		—		—		—

(1) No amounts were reclassified from AOCL into income related to the sale of a subsidiary.

Interest Rate Risk Management

The Company may use interest rate swap contracts on certain investing and borrowing transactions to manage its net exposure to interest rate changes and to reduce its overall cost of borrowing. The Company does not use leveraged swaps and, in general, does not leverage any of its investment activities that would put principal at risk.

At ~~September~~March 3031, ~~2025~~2026, the Company was a party to ~~seven~~ten pay-floating, receive-fixed interest rate swap contracts designated as fair value hedges of a portion of fixed-rate notes as detailed in the table below.

	September 30, 2025
	March 31, 2026
($ in millions)	Par Value of Debt		Number of Interest Rate Swaps Held	Total Swap Notional Amount
4.50% notes due 2033	$	1,500	6	$	1,500
5.00% notes due 2053	1,500		1	250
4.75% notes due 2035	1,500		2	500
5.00% notes due 2053	1,500		2	500

The interest rate swap contracts are designated hedges of the fair value changes in the notes attributable to changes in the benchmark Secured Overnight Financing Rate (SOFR) swap rate. The fair value changes in the notes attributable to changes in the SOFR swap rate are recorded in interest expense along with the offsetting fair value changes in the swap contracts. The cash flows from these contracts are reported as operating activities in the Condensed Consolidated Statement of Cash Flows. In February 2026, the Company entered into two forward starting swaps, each with a notional amount of $250 million.

The table below presents the location of amounts recorded in the Condensed Consolidated Balance Sheet related to cumulative basis adjustments for fair value hedges:

Carrying Amount of Hedged Liabilities

Cumulative Amount of Fair Value Hedging Adjustment Increase Included in the Carrying Amount

($ in millions)

~~September~~March 3031, ~~2025~~2026

December 31, ~~2024~~2025

~~September~~March 3031, ~~2025~~2026

December 31, ~~2024~~2025

Balance Sheet Caption

Long-Term Debt

12,~~819~~539

1,~~509~~810

8057

1770

~~Presented~~- in14 the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments:-

		September 30, 2025						December 31, 2024
		Fair Value of Derivative				U.S. DollarNotional		Fair Value of Derivative				U.S. DollarNotional
($ in millions)		Asset		Liability				Asset		Liability
Derivatives Designated as Hedging Instruments	Balance Sheet Caption
Interest rate swap contracts	Other Assets	$	80	$	—	$	1,750	$	17	$	—	$	1,500
Foreign exchange contracts	Other current assets	55		—		4,681		323		—		8,662
Foreign exchange contracts	Other Assets	37		—		2,274		66		—		2,125
Foreign exchange contracts	Accrued and other current liabilities	—		246		5,694		—		1		162
Foreign exchange contracts	Other Noncurrent Liabilities	—		—		—		—		1		16
		$	172	$	246	$	14,399	$	406	$	2	$	12,465
Derivatives Not Designated as Hedging Instruments	Balance Sheet Caption
Foreign exchange contracts	Other current assets	$	144	$	—	$	12,498	$	323	$	—	$	12,544
Foreign exchange contracts	Accrued and other current liabilities	—		246		15,975		—		343		13,551
		$	144	$	246	$	28,473	$	323	$	343	$	26,095
		$	316	$	492	$	42,872	$	729	$	345	$	38,560

- 16 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Presented in the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments:


		March 31, 2026						December 31, 2025
		Fair Value of Derivative				U.S. Dollar Notional		Fair Value of Derivative				U.S. Dollar Notional
($ in millions)		Asset		Liability				Asset		Liability
Derivatives Designated as Hedging Instruments	Balance Sheet Caption
Interest rate swap contracts	Other Assets	$	58	$	—	$	2,500	$	71	$	—	$	1,750
Interest rate contracts	Other Assets	8		—		500		—		—		—
Foreign exchange contracts	Other current assets	247		—		7,751		113		—		6,430
Foreign exchange contracts	Other Assets	55		—		1,828		32		—		1,793
Foreign exchange contracts	Accrued and other current liabilities	—		48		3,705		—		131		4,726
Foreign exchange contracts	Other Noncurrent Liabilities	—		1		33		—		1		13
		$	368	$	49	$	16,317	$	216	$	132	$	14,712
Derivatives Not Designated as Hedging Instruments	Balance Sheet Caption
Foreign exchange contracts	Other current assets	$	194	$	—	$	13,870	$	107	$	—	$	11,643
Foreign exchange contracts	Accrued and other current liabilities	—		180		11,919		—		191		13,579
Foreign exchange contracts	Other Noncurrent Liabilities	—		—		—		—		1		357
		$	194	$	180	$	25,789	$	107	$	192	$	25,579
		$	562	$	229	$	42,106	$	323	$	324	$	40,291

As noted above, the Company records its derivatives on a gross basis in the Condensed Consolidated Balance Sheet. The Company has master netting agreements with several of its financial institution counterparties (see Concentrations of Credit Risk below). The following table provides information on the Company’s derivative positions subject to these master netting arrangements as if they were presented on a net basis, allowing for the right of offset by counterparty and cash collateral exchanged per the master agreements and related credit support annexes:

September 30, 2025

December 31, 2024

March 31, 2026

December 31, 2025

($ in millions)

Asset

Liability

Asset

Liability

Gross amounts recognized in the condensed consolidated balance sheet

~~316~~562

~~492~~229

~~729~~323

~~345~~324

Gross amounts subject to offset in master netting arrangements not offset in the condensed consolidated balance sheet

(~~246~~225)

(~~299~~245)

Cash collateral received

(189)

—

(~~165~~1)

—

Net amounts

69248

~~246~~4

~~265~~77

4679

The table below provides information regarding the location and amount of pretax gains and losses of derivatives designated in fair value or cash flow hedging relationships:

	Three Months Ended September 30,												Nine Months Ended September 30,
	Three Months Ended March 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~2026		~~2024~~2025		~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~		~~2025~~		~~2024~~		~~2025~~		~~2024~~
Financial Statement Caption in which Effects of Fair Value or Cash Flow Hedges are Recorded	Sales				Other (income) expense, net (1)				Other comprehensive income (loss)				~~Sales~~				~~Other (income) expense, net (1)~~				~~Other comprehensive income (loss)~~
	$	1716,~~276~~286	$	1615,~~657~~529	$	~~(238)~~138	$	(~~162~~35)	$	~~219~~227	$	(1020)	$	~~48,611~~	$	~~48,544~~	$	~~(281)~~	$	~~(151)~~	$	~~(257)~~	$	~~(210)~~
Loss (gain) on fair value hedging relationships:
(Gain) loss on fair value hedging relationships:
Interest rate swap contracts
Hedged items	—		—		4(14)		6838		—		—		—		—		62		42		—		—
Derivatives designated as hedging instruments	—		—		~~(5)~~13		(6939)		—		—		—		—		~~(63)~~		~~(43)~~		—		—
Impact of cash flow hedging relationships:
Foreign exchange contracts
Amount of gain (loss) recognized in OCI on derivatives	—		—		—		—		~~113~~168		(~~325~~201)		—		—		—		—		~~(630)~~		22
(Decrease) increase in Sales as a result of AOCL reclassifications	(8598)		4874		—		—		8598		(4874)		~~(35)~~		~~146~~		—		—		35		~~(146)~~
Interest rate contracts
Amount of gain recognized in Other (income) expense, net on derivatives	—		—		—(1)		—		—		—		—		—		~~(1)~~		~~(1)~~		—		—
Amount of gain (loss) recognized in OCI on derivatives	—		—		—		—		18		—		—		—		—		—		17		(1)
Amount of gain recognized in OCI on derivatives	—		—		—		—		7		—

(1) Interest expense is a component of Other (income) expense, net.

- 15 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The table below provides information regarding the income statement effects of derivatives not designated as hedging instruments:

Amount of Derivative Pretax Loss (Gain) Recognized in Income

Three Months Ended September 30,

Nine Months Ended September 30,

Three Months Ended March 31,

($ in millions)

~~2025~~2026

~~2024~~2025

~~2025~~

~~2024~~

Derivatives Not Designated as Hedging Instruments

Income Statement Caption

Foreign exchange contracts (1)

Other (income) expense, net

3936

(~~139~~20)

~~(217)~~

~~(65)~~

Foreign exchange contracts (2)

Sales

~~(8)~~12

1016

~~(10)~~

(1) These derivative contracts primarily mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates.

(2) These derivative contracts serve as economic hedges of forecasted transactions.

At ~~September~~March 3031, ~~2025~~2026, the Company estimates $~~298~~69 million of pretax net unrealized ~~losses~~gains on derivatives maturing within the next 12 months that hedge foreign currency denominated sales over that same period will be reclassified from AOCL to Sales. The amount ultimately reclassified to Sales may differ as foreign exchange rates change. Realized gains and losses are ultimately determined by actual foreign exchange rates at maturity.

- 17 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Investments in Debt and Equity Securities

Information on investments in debt and equity securities is as follows:

	September 30, 2025								December 31, 2024
	March 31, 2026								December 31, 2025
	AmortizedCost		Gross Unrealized				FairValue		AmortizedCost		Gross Unrealized				FairValue
($ in millions)			Gains		Losses						Gains		Losses
U.S. government and agency securities	$	99	$	—	$	—	$	99	$	188	$	—	$	—	$	188
Commercial paper	$	375	$	—	$	—	$	375	$	—	$	—	$	—	$	—
Commercial paper	45		—		—		45		348		—		—		348
U.S. government and agency securities	100		—		—		100		100		—		—		100
Foreign government bonds	1		—		—		1		—1		—		—		—1
Total debt securities	$	~~145~~476	$	—	$	—	$	~~145~~476	$	~~536~~101	$	—	$	—	$	~~536~~101
Publicly traded equity securities (1)							1,~~546~~571								~~920~~1,392
Total debt and publicly traded equity securities							$	12,~~691~~047							$	1,~~456~~493

(1) Unrealized net gains of $~~367~~126 million ~~and $630 million~~ were recorded in Other (income) expense, net in the ~~third~~first quarter ~~and first nine months~~ of ~~2025,~~2026 ~~respectively,~~ on equity securities still held at ~~September~~March 3031, ~~2025~~2026. Unrealized net ~~losses (~~gains) of $42115 million ~~and $(82) million~~ were recorded in Other (income) expense, net in the ~~third~~first quarter ~~and first nine months~~ of ~~2024,~~2025 ~~respectively,~~ on equity securities still held at ~~September~~March 3031, ~~2024~~2025.

At ~~September~~March 3031, ~~2025~~2026 and ~~September~~March 3031, ~~2024~~2025, the Company also had $~~834~~881 million and $~~848~~872 million, respectively, of equity investments without readily determinable fair values included in Other Assets. The Company records unrealized gains on these equity investments based on favorable observable price changes from transactions involving similar investments of the same investee and records unrealized losses based on unfavorable observable price changes, which are included in Other (income) expense, net. During the first ~~nine~~quarter ~~months~~ of ~~2025~~2026, the Company recorded unrealized gains of $135 million ~~and unrealized losses of $33 million~~ related to certain of these equity investments still held at ~~September~~March 3031, ~~2025~~2026. During the first ~~nine~~quarter ~~months~~ of ~~2024~~2025, the Company recorded unrealized ~~gains of $12 million and unrealized~~ losses of $2511 million related to certain of these equity investments still held at ~~September~~March 3031, ~~2024~~2025. Cumulative unrealized gains and cumulative unrealized losses based on observable price changes for investments in equity investments without readily determinable fair values still held at ~~September~~March 3031, ~~2025~~2026 were $~~293~~320 million and $~~131~~164 million, respectively.

At ~~September~~March 3031, ~~2025~~2026 and ~~September~~March 3031, ~~2024~~2025, the Company also had $~~226~~229 million and $~~328~~249 million, respectively, recorded in Other Assets for equity securities held through ownership interests in investment funds. ~~Losses~~ (~~gains~~Gains) losses recorded in Other (income) expense, net relating to these investment funds were $~~2 million and $~~(213) million ~~for the third quarter of 2025~~ and ~~2024, respectively, and were~~ $53 23 million ~~and $(26) million~~ for the first ~~nine~~quarter ~~months~~ of ~~2025~~2026 and ~~2024~~2025, respectively.

Fair Value Measurements

Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The Company uses a fair value hierarchy which maximizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. There are three levels of inputs used to measure fair value with Level 1 having the highest priority and Level 3 having the lowest:

Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities.

Level 2 - Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3 - Unobservable inputs that are supported by little or no market activity. Level 3 assets or liabilities are those whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques with significant unobservable inputs, as well as assets or liabilities for which the determination of fair value requires significant judgment or estimation.

If- ~~the~~16 inputs used to measure the financial assets and liabilities fall within more than one level described above, the categorization is based on the lowest level input that is significant to the fair value measurement of the instrument.-

- 18 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

If the inputs used to measure the financial assets and liabilities fall within more than one level described above, the categorization is based on the lowest level input that is significant to the fair value measurement of the instrument.

Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis

Financial assets and liabilities measured at fair value on a recurring basis are summarized below:

	Fair Value Measurements Using								Fair Value Measurements Using
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
($ in millions)	~~September~~March 3031, ~~2025~~2026								December 31, ~~2024~~2025
Assets
Investments
Commercial paper	$	—	$	45375	$	—	$	45375	$	—	$	~~348~~—	$	—	$	~~348~~—
Foreign government bonds	—		1		—		1		—		—1		—		—1
U.S. government and agency securities	—		—		—		—		—		99		—		99
Publicly traded equity securities	1,104		—		—		1,104		955		—		—		955
Publicly traded equity securities	1,116		—		—		1,116		463		—		—		463
	1,104		376		—		1,480		955		1		—		956
	1,116		46		—		1,162		463		447		—		910
Other assets (1)
U.S. government and agency securities	99100		—		—		99100		89100		—		—		89100
Publicly traded equity securities (2)	~~430~~467		—		—		~~430~~467		~~457~~437		—		—		~~457~~437
	529		—		—		529		546		—		—		546
	567		—		—		567		537		—		—		537
Derivative assets (3)
Forward exchange contracts	—		~~169~~310		—		~~169~~310		—		~~499~~168		—		~~499~~168
Interest rate swaps	—		80		—		80		—		17		—		17
Purchased currency options	—		186		—		186		—		84		—		84
Purchased currency options	—		67		—		67		—		213		—		213
Interest rate swaps	—		58		—		58		—		71		—		71
	—		316		—		316		—		729		—		729
Interest rate contracts	—		8		—		8		—		—		—		—
Total assets	$	1,645	$	362	$	—	$	2,007	$	1,009	$	1,176	$	—	$	2,185
	—		562		—		562		—		323		—		323
Total assets	$	1,671	$	938	$	—	$	2,609	$	1,492	$	324	$	—	$	1,816
Liabilities
Other liabilities
Contingent consideration	$	—	$	—	$	—	$	—	$	—	$	—	$	193	$	193
Derivative liabilities (3)
Forward exchange contracts	—$	—	~~461~~$	202	—$	—	~~461~~$	202	—$	—	~~338~~$	293	—$	—	~~338~~$	293
Written currency options	—		3127		—		3127		—		731		—		731
	—		492		—		492		—		345		—		345
Total liabilities	$	—	$	229	$	—	$	229	$	—	$	324	$	—	$	324
Total liabilities	$	—	$	492	$	—	$	492	$	—	$	345	$	193	$	538

(1) Investments included in other assets are restricted as to use, including for the payment of benefits under employee benefit plans.

(2) ~~Includes~~Balance at March 31, 2026 includes securities with ana ~~aggregate~~ fair value of $81 17 million atthat ~~December 31,~~are ~~2024~~subject to a contractual sale restriction that expires in July 2026, ~~which~~and ~~were~~securities with a fair value of $18 million that are subject to a contractual sale restriction that ~~expired~~expires in ~~April~~August ~~2025~~2026.

(3) The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant.

As of ~~September~~March 3031, ~~2025~~2026 and December 31, ~~2024~~2025, Cash and cash equivalents included $174.54 billion and $1213.38 billion of cash equivalents, respectively (which would be considered Level 2 in the fair value hierarchy).

Contingent Consideration

Summarized information about the changes in the fair value of liabilities for contingent consideration associated with business combinations is as follows:

($ in millions)	2025		2024
Fair value January 1	$	193	$	354
Changes in estimated fair value (1)	(52)		2
Payments (2)	(141)		(148)
Fair value September 30	$	—	$	208

(1) Recorded in Cost of sales, Research and development expenses, and Other (income) expense, net. Includes cumulative translation adjustments. Amount in 2025 includes the reversal of $45 million for a Zerbaxa sales-based milestone as it was determined that payment was not probable.

(2) Amount in both periods reflects payments related to the 2016 termination of the Sanofi Pasteur MSD joint venture. Amount in 2025 also includes a $25 million payment related to the achievement of a sales-based milestone for Zerbaxa.

Other Fair Value Measurements

Some of the Company’s financial instruments, such as cash and cash equivalents, receivables and payables, are reflected in the balance sheet at carrying value, which approximates fair value due to their short-term nature.

The estimated fair value of loans payable and long-term debt (including current portion) at ~~September~~March 3031, ~~2025~~2026, was $3744.7 billion compared with a carrying value of $4149.41 billion and at December 31, ~~2024~~2025, was $3245.6 billion compared with a carrying value of $3749.13 billion. Fair value was estimated using recent observable market prices and would be considered Level 2 in the fair value hierarchy.

- 19 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Concentrations of Credit Risk

On an ongoing basis, the Company monitors concentrations of credit risk associated with corporate and government issuers of securities and financial institutions with which it conducts business. Credit exposure limits are established to limit a concentration with any single issuer or institution. Cash and investments are placed in instruments that meet high credit quality standards as specified in the Company’s investment policy guidelines.

The majority of the Company’s accounts receivable arise from product sales in the U.S. and Europe and are primarily due from drug wholesalers, distributors and retailers, hospitals and government agencies. The Company monitors the financial performance and creditworthiness of its customers so that it can properly assess and respond to changes in their credit profile. The Company also continues to monitor global economic conditions, including the volatility associated with international sovereign economies, and associated impacts on the financial markets and its business.

The Company has accounts receivable factoring agreements with financial institutions in certain countries to sell accounts receivable. The Company factored $1.76 billion ~~and $2.1 billion~~ of accounts receivable as of ~~September~~both March 3031, ~~2025~~2026 and December 31, ~~2024,~~2025 ~~respectively,~~ under these factoring arrangements, which reduced outstanding accounts receivable. The cash received from the financial institutions is reported within operating activities in the Condensed Consolidated Statement of Cash Flows. In certain of these factoring arrangements, for ease of administration, the Company will collect customer payments related to the factored receivables, which it then remits to the financial institutions, generally within thirty days after receipt. As of ~~September~~March ~~30, 2025 and December~~ 31, ~~2024,~~2026 ~~the Company had collected $35 million~~ and $55 million, respectively, on behalf of the financial institutions, which is reflected as restricted cash in Other current assets, and the related obligation to remit the cash is recorded in Accrued and other current liabilities. The net cash flows related to these collections are reported as financing activities in the Condensed Consolidated Statement of Cash Flows. The cost of factoring such accounts receivable was de minimis.

~~Derivative~~- ~~financial~~17 instruments are executed under International Swaps and Derivatives Association master agreements. The master agreements with several of the Company’s financial institution counterparties also include credit support annexes. These annexes contain provisions that require collateral to be exchanged depending on the value of the derivative assets and liabilities, the Company’s credit rating, and the credit rating of the counterparty. Cash collateral received by the Company from various counterparties was $1 million and $165 million at September 30, 2025 and December 31, 2024, respectively. The obligation to return such collateral is recorded in Accrued and other current liabilities. -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

December 31, 2025, the Company had collected $39 million and $45 million, respectively, on behalf of the financial institutions, which is reflected as restricted cash in Other current assets, and the related obligation to remit the cash is recorded in Accrued and other current liabilities. The net cash flows related to these collections are reported as financing activities in the Condensed Consolidated Statement of Cash Flows. The cost of factoring such accounts receivable was de minimis.

Derivative financial instruments are executed under International Swaps and Derivatives Association master agreements. The master agreements with several of the Company’s financial institution counterparties also include credit support annexes. These annexes contain provisions that require collateral to be exchanged depending on the value of the derivative assets and liabilities, the Company’s credit rating, and the credit rating of the counterparty. Cash collateral received by the Company from various counterparties was $89 million and $1 million at March 31, 2026 and December 31, 2025, respectively. The obligation to return such collateral is recorded in Accrued and other current liabilities.

6. Inventories

Inventories consisted of:

($ in millions)	~~September~~March 3031, ~~2025~~2026		December 31, ~~2024~~2025
Finished goods	$	2,~~249~~211	$	2,~~022~~275
Raw materials and work in process	1011,~~165~~136		810,~~831~~645
Supplies	~~325~~334		~~289~~331
Total	1213,~~739~~681		1113,~~142~~251
Decrease to LIFO cost	(~~883~~1,007)		(~~840~~912)
	$	1112,~~856~~674	$	1012,~~302~~339
Recognized as:
Inventories	$	6,~~444~~479	$	6,~~109~~658
Other Assets	56,~~412~~195		45,~~193~~681

Amounts recognized as Other Assets are comprised almost entirely of raw materials and work in process inventories. At ~~September~~March 3031, ~~2025~~2026 and December 31, ~~2024~~2025, these amounts included $5.28 billion and $35.85 billion, respectively, of inventories not expected to be sold within one year. In addition, these amounts included $~~167~~360 million and $~~412~~211 million at ~~September~~March 3031, ~~2025~~2026 and December 31, ~~2024~~2025, respectively, of inventories produced in preparation for product launches.

7. ~~Long-Term~~Loans ~~Debt~~Payable

In ~~September~~April ~~2025~~2026, Merck entered into a delayed draw term loan credit agreement (Credit Agreement) pursuant to which the ~~Company~~lenders ~~issued~~have ~~$6.0 billion~~committed ~~aggregate~~(subject ~~principal~~to ~~amount~~satisfaction of ~~senior~~certain ~~unsecured~~conditions ~~notes~~set ~~consisting~~forth ofin ~~$500 million~~the ofCredit ~~floating~~Agreement) ~~rate~~to ~~notes~~provide ~~due~~Merck ~~2027,~~with ~~$750 million~~financing ofunder ~~3.85%~~a ~~notes~~364-day ~~due~~term ~~2027,~~loan ~~$750 million~~facility ofin ~~4.15%~~an ~~notes~~aggregate ~~due~~amount ~~2030,~~not to exceed $16.0 billion. ofBorrowings ~~4.55%~~under ~~notes~~the ~~due~~Credit ~~2032,~~Agreement ~~$1.75 billion~~will bear interest at an annual rate of 4the SOFR rate plus 0.9550% ~~notes~~from ~~due~~the ~~2035~~date loans are borrowed (Funding Date) to the date that is 180 days from the Funding Date, and ~~$1.25 billion~~then ofthe ~~5.70%~~SOFR ~~notes~~rate ~~due~~plus ~~2055~~0.75% thereafter. The Company ~~used~~has ~~the~~given ~~net~~required ~~proceeds~~notice to the lenders of its intention to draw down the ~~offering~~$6.0 billion ~~for~~of ~~general~~funds ~~corporate~~under ~~purposes~~the facility, ~~including~~which will be used to fund a portion of the approximately $106.5 7 billion cash consideration ~~and~~for ~~related~~the ~~fees~~acquisition ~~and~~of ~~expenses~~Terns. ~~payable~~The inCompany ~~connection~~intends ~~with~~to ~~Merck’s~~use ~~acquisition~~the ofproceeds ~~Verona~~from ~~Pharma~~a inlong-term ~~October~~debt ~~2025~~financing ~~(see~~to ~~Note 2)~~repay borrowings under the Credit Agreement.

- 20 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

8. Contingencies

The Company is involved in various claims and legal proceedings of a nature considered normal to its business, including product liability, intellectual property, commercial litigation, and securities litigation, as well as certain additional matters including governmental and environmental matters. In the opinion of the Company, it is unlikely that the resolution of these matters will be material to the Company’s financial condition, results of operations or cash flows.

Given the nature of the litigation discussed below and the complexities involved in these matters, the Company is unable to reasonably estimate a possible loss or range of possible loss for such matters until the Company knows, among other factors, (i) what claims, if any, will survive dispositive motion practice, (ii) the extent of the claims, including the size of any potential class, particularly when damages are not specified or are indeterminate, (iii) how the discovery process will affect the litigation, (iv) the settlement posture of the other parties to the litigation and (v) any other factors that may have a material effect on the litigation.

The Company records accruals for contingencies when it is probable that a liability has been incurred and the amount can be reasonably estimated. These accruals are adjusted periodically as assessments change or additional information becomes available. Generally, for product liability claims, a portion of the overall accrual is actuarially determined and considers such factors as past experience, number of claims reported and estimates of claims incurred but not yet reported. Individually significant contingent losses are accrued when probable and reasonably estimable. Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable.

- 18 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The Company’s decision to obtain insurance coverage is dependent on market conditions, including cost and availability, existing at the time such decisions are made. The Company has evaluated its risks and has determined that the cost of obtaining product liability insurance outweighs the likely benefits of the coverage that is available and, as such, has no insurance for most product liabilities.

Product Liability Litigation

Dr. Scholl’s Foot Powder

As previously disclosed, Merck is a defendant in product liability lawsuits in the U.S. arising from consumers’ alleged exposure to talc in Dr. Scholl’s foot powder, which Merck acquired through its merger with Schering-Plough Corporation and sold as part of the divestiture of Merck’s consumer care business to Bayer in 2014. In these actions, plaintiffs allege that they were exposed to asbestos-contaminated talc and developed mesothelioma as a result. As of ~~September~~March 3031, ~~2025~~2026, approximately ~~605~~735 cases were pending against Merck in various state courts.

The Company was recently the defendant in a trial in Chicago, Illinois, in which it was found to be not liable for the plaintiff’s mesothelioma. The Company anticipates that there will be additional trials in the Dr. Scholl’s litigation in the future.

Gardasil/Gardasil 9

As previously disclosed, Merck is a defendant in product liability lawsuits in the U.S. involving Gardasil (Human Papillomavirus Quadrivalent [Types 6, 11, 16 and 18] Vaccine, Recombinant) and Gardasil 9 (Human Papillomavirus 9-valent Vaccine, Recombinant). As of ~~September~~March 3031, ~~2025~~2026, approximately 135 cases were filed and are pending against Merck in either federal or state court. In these actions, plaintiffs allege, among other things, that they suffered various personal injuries after vaccination with Gardasil or Gardasil 9, with postural orthostatic tachycardia syndrome (POTS) as a predominate alleged injury.

In August 2022, the U.S. Judicial Panel on Multidistrict Litigation ordered that Gardasil/Gardasil 9 product liability cases pending in federal courts nationwide be transferred to Judge Robert J. Conrad in the Western District of North Carolina for coordinated pre-trial proceedings. In February 2024, the multidistrict litigation (Gardasil MDL) was reassigned to Judge Kenneth D. Bell. On March 11, 2025, the court granted Merck’s motion for summary judgment in 16 bellwether cases on implied preemption grounds; plaintiffs have appealed to the Fourth Circuit. The parties’ letter submissions on next steps in the Gardasil MDL proceeding in light of the court’s decision were submitted on April 8, 2025. Expert discovery on the remaining alleged conditions and summary judgment briefing are to follow.

On ~~March~~January 2128, 2025, ~~plaintiff’s~~a ~~co-lead~~trial ~~counsel~~commenced in ~~the~~California ~~Gardasil~~state ~~MDL~~court. ~~filed~~Plaintiff aclaims ~~seven-plaintiff~~that ~~complaint~~she insuffers ~~New~~from ~~Jersey~~POTS ~~state~~and ~~court~~fibromyalgia as a result of her Gardasil vaccinations. On ~~March~~February 2414, 2025, ~~Merck~~after ~~removed~~several ~~the~~weeks ~~case~~of trial and an opportunity to ~~federal~~litigate ~~court~~plaintiff’s ~~and~~claims ~~requested~~before ~~that~~a ~~the~~jury, ~~U.S.~~plaintiff’s ~~Judicial~~counsel ~~Panel~~approached onMerck ~~Multidistrict~~and ~~Litigation~~proposed ~~transfer~~that the ~~case~~jury tobe discharged and the ~~Gardasil~~case ~~MDL~~adjourned. ~~Plaintiffs~~Merck ~~opposed~~agreed, ~~transfer~~subject to ~~the~~an ~~Gardasil~~explicit ~~MDL~~stipulation ~~and~~that ~~moved~~Merck towould ~~have~~provide no financial or other consideration in exchange for the agreement to adjourn. The case ~~remanded~~has tobeen ~~New~~adjourned ~~Jersey~~until ~~state~~a ~~court.~~new Ontrial ~~August~~date 7,of ~~2025~~July 27, ~~the U~~2026.S. ~~Judicial~~Merck ~~Panel~~is onvigorously ~~Multidistrict~~defending ~~Litigation~~this ~~issued~~case anand ~~order~~believes ~~transferring~~that ~~the~~evidence ~~case~~presented toin ~~the~~court will show that Gardasil ~~MDL~~had no role in causing any of plaintiff’s conditions.

OnAs ~~May~~previously 1disclosed, in October 2025, ~~plaintiff’s~~Merck ~~co-lead~~entered into a proposed agreement with plaintiffs’ counsel into substantially resolve the Gardasil ~~MDL~~product ~~filed~~liability alitigation. ~~new~~The ~~six-plaintiff~~proposed ~~complaint~~agreement insets ~~New~~forth ~~Jersey~~various ~~state~~terms ~~court.~~and Onconditions ~~May~~under ~~30,~~which ~~2025,~~ Merck ~~removed~~would resolve the ~~case~~bulk toof ~~federal~~all ~~court~~pending ~~and~~Gardasil ~~has~~product ~~requested~~liability ~~that~~claims in the U.S. ~~Judicial~~in ~~Panel~~exchange onfor ~~Multidistrict~~a ~~Litigation~~total ~~transfer~~payment ~~the~~that ~~case~~is toconsiderably ~~the~~less ~~Gardasil~~than ~~MDL.~~Merck’s ~~Plaintiffs~~anticipated ~~have~~costs ~~opposed~~of ~~transfer~~defense toin the ~~Gardasil~~litigation ~~MDL~~ and ~~have~~that ~~moved~~is not material to ~~have~~Merck. The proposed agreement requires that several conditions be met within specified time periods, including participation thresholds, in order for the ~~case~~proposed ~~remanded~~agreement to ~~New~~result ~~Jersey~~in ~~state~~a ~~court~~final resolution of any pending litigation.

On July 11, 2025, plaintiff’s co-lead counsel in the Gardasil MDL filed a new six-plaintiff complaint in New Jersey state court. On July 11, 2025, Merck removed the case to federal court and has requested that the U.S. Judicial Panel on Multidistrict Litigation transfer the case to the Gardasil MDL. Plaintiffs have opposed transfer to the Gardasil MDL and have moved to have the case remanded to New Jersey state court.

On January 28, 2025, a trial commenced in California state court. Plaintiff claims that she suffers from POTS and fibromyalgia as a result of her Gardasil vaccinations. On February 14, 2025, after several weeks of trial and an opportunity to litigate plaintiff’s claims before a jury, plaintiff’s counsel approached Merck and proposed that the jury be discharged and the case adjourned. Merck agreed, subject to an explicit stipulation that Merck would provide no financial or other consideration in

- 21 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

exchange for the agreement to adjourn. The case has thus been adjourned until a new trial date of February 2, 2026. Merck is vigorously defending this case and believes that evidence presented in court will show that Gardasil had no role in causing any of plaintiff’s conditions.

In October 2025, Merck entered into a proposed agreement with plaintiffs’ counsel to substantially resolve the Gardasil product liability litigation. The proposed agreement sets forth various terms and conditions under which Merck would resolve the bulk of all pending Gardasil product liability claims in the U.S. in exchange for a total payment that is considerably less than Merck’s anticipated costs of defense in the litigation and that is not material to Merck. The proposed agreement requires that several conditions be met within specified time periods, including participation thresholds, in order for the proposed agreement to result in a final resolution of any pending litigation.

As previously disclosed, there are fewer than 15 product liability cases pending outside the U.S.

Governmental Proceedings

Civil Investigative ~~Demand~~Demands

InAs previously disclosed, in August 2025, the Company received a Civil Investigative Demand (CID) from the U.S. Department of Justice (DOJ), pursuant to a False Claims Act investigation, seeking documents, information, and testimony related to the Company’s programs and practices concerning diversity, equity, and inclusion. The CID states that the DOJ is investigating whether, in connection with the Company’s claims for payments under its federal contracts, the Company falsely certified compliance with federal antidiscrimination laws. The Company is cooperating with the investigation.

As previously disclosed, in June 2024, Merck received a CID from the DOJ, pursuant to a False Claims Act investigation, seeking documents and materials related to Steglatro, Januvia and certain related drugs. The CID states that it is investigating Merck’s price reporting under the Medicaid Drug Rebate Program as well as compliance with anti-kickback requirements in connection with patient assistance programs. The Company is cooperating with the investigation.

Other Matters

As previously disclosed, from time to time, the Company’s subsidiaries in China receive inquiries regarding their operations from various Chinese governmental agencies. Some of these inquiries may be related to matters involving other multinational pharmaceutical companies, as well as Chinese entities doing business with such companies. The Company’s policy is to cooperate with these authorities and to provide responses as appropriate.

- 19 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

As previously disclosed, from time to time, the Company receives inquiries and is the subject of preliminary investigation activities from competition and other governmental authorities in markets outside the U.S. These authorities may include regulators, administrative authorities, and law enforcement and other similar officials, and these preliminary investigation activities may include site visits, formal or informal requests or demands for documents or materials, inquiries or interviews and similar matters. Certain of these preliminary inquiries or activities may lead to the commencement of formal proceedings. Should those proceedings be determined adversely to the Company, monetary fines and/or remedial undertakings may be required.

Securities Litigation

As previously disclosed, on February 12, 2025, a putative class action was filed against Merck and certain of its officers in the U.S. District Court for the District of New Jersey, captioned Cronin v. Merck & Co., Inc., et al., purportedly on behalf of all purchasers of Merck common stock between ~~February~~October ~~2022~~26, 2023, and February 3, 2025. Plaintiff alleges that Merck violated federal securities laws by making materially false and misleading statements and ~~material~~ omissions regarding demand for Gardasil/Gardasil 9 in China. ~~Plaintiff~~On ~~seeks~~December ~~unspecified~~17, ~~monetary damages~~2025, ~~pre-judgment~~the ~~and~~court ~~post-judgment~~appointed ~~interest,~~AMF ~~and~~Tjänstepension ~~fees~~AB, ~~and~~KBC ~~costs.~~Asset OnManagement ~~April 7~~NV, ~~2025,~~and ~~the~~Wayne ~~court~~County ~~entered~~Employees’ aRetirement ~~joint~~System ~~stipulation~~as ~~staying~~lead ~~the~~plaintiffs ~~defendants’~~(Lead ~~deadline~~Plaintiffs). toLead ~~respond~~Plaintiffs tofiled ~~the~~an amended complaint ~~until~~on ~~after~~February a20, ~~lead~~2026, ~~plaintiff~~seeking isunspecified ~~appointed~~damages ~~and~~allegedly ~~requiring~~caused by the ~~parties~~purported tofalse ~~confer~~or ~~and~~misleading ~~jointly~~statements. ~~propose~~Defendants ~~deadlines~~filed ~~for~~a ~~amending~~motion ~~and~~to ~~responding~~dismiss toon ~~the~~May ~~complaint~~1, ~~within~~2026. 14The ~~days~~opposition ofbrief ~~the~~is ~~lead~~due ~~plaintiff~~June ~~appointment.~~30, ~~Lead~~2026 ~~plaintiff~~and ~~motions~~the ~~were~~reply ~~filed~~brief onis ~~April~~due August 14, ~~2025, and remain pending~~2026.

As previously disclosed, onvarious ~~July~~derivative ~~18,~~lawsuits ~~2025,~~were ~~purported Merck stockholder Terence Collins~~ filed ~~a derivative lawsuit~~ in ~~the U.S. District Court for the District of~~ New Jersey, ~~captioned~~state ~~Collins~~and v.federal ~~Davis,~~court ~~et al.,~~ against certain current and former Merck officers and board members. The ~~complaint~~derivative ~~asserts~~lawsuits assert claims ofunder ~~violation~~state ofand ~~Section~~federal ~~14(a)~~securities ~~of the Securities Act of 1934 (the Exchange Act)~~statutes, ~~breach~~as ofwell ~~fiduciary~~as ~~duty,~~New ~~waste~~Jersey ofcommon ~~corporate assets~~law, ~~and unjust enrichment~~ based on the same allegations as those made in the putative securities class action. OnThese ~~behalf~~derivative oflawsuits ~~the~~seek ~~Company, the complaint seeks~~ unspecified monetary damages, corporate governance reforms, injunctive relief, disgorgement of profits, restitution, ~~and~~ fees, and costs. All the derivative proceedings are stayed pending further developments in the class action.

On September 2, 2025, purported Merck stockholders Robert Daniel and Daniel Gershen filed a derivative lawsuit in the U.S. District Court for the District of New Jersey, captioned Daniel, et al. v. Frazier, et al., against certain current and former Merck officers and board members for violations of Sections 10(b), 14(a), and 20(a) of the Exchange Act, breach of fiduciary duty, waste of corporate assets, and unjust enrichment based on the same allegations as the putative securities class action and the earlier-filed Collins derivative lawsuit. On behalf of the Company, the complaint seeks unspecified monetary damages, corporate governance reforms, injunctive relief, restitution, and fees and costs.

On September 19, 2025, the parties to the Collins and Daniel lawsuits concurrently filed joint stipulations to stay the lawsuits pending the earliest of the following: (i) dismissal of the securities class action; (ii) any defendant filing an answer in the securities class action; or (iii) any party to the stipulation giving 15 days’ notice that they no longer consent to the stay. The parties also filed joint stipulations to consolidate the Collins and Daniel derivative lawsuits. On October 1, 2025, the district court so-ordered the stay stipulations. The court has not yet taken action in response to the consolidation stipulations.

On September 23, 2025, purported Merck shareholders Gary Weniger, Kathie McGinty, and Pamela Young filed a derivative lawsuit in the Superior Court of New Jersey (Union County), captioned Weniger, et al. v. Frazier, et al., against certain

- 22 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

current and former Merck officers and board members. The complaint asserts claims of breach of fiduciary duty, gross mismanagement, waste of corporate assets, unjust enrichment, insider trading, and a violation of New Jersey securities law based on the same allegations as the putative securities class action and the earlier-filed Collins and Daniel derivative lawsuits. On behalf of the Company, the complaint seeks unspecified monetary damages, disgorgement of any illicitly gained proceeds, corporate governance reforms, injunctive relief, restitution, and fees and costs.

Commercial and Other Litigation

~~Zetia~~RotaTeq Antitrust Litigation

As previously disclosed, ~~Merck,~~in ~~MSD,~~March ~~Schering Corporation~~2023, ~~Schering-Plough~~the ~~Corporation,~~Mayor and ~~MSP~~City ~~Singapore~~Council ~~Company~~of ~~LLC~~Baltimore ~~(collectively,~~filed ~~the~~a ~~Merck~~putative ~~Defendants)~~class ~~were~~action ~~defendants~~against MSD in athe ~~number~~Eastern District of ~~lawsuits~~Pennsylvania ~~filed~~on behalf of all third-party payers in ~~2018~~states onthat ~~behalf~~indirectly ofpurchased, ~~direct~~paid, and/or ~~indirect~~provided ~~purchasers~~reimbursement for some or all of ~~Zetia~~the purchase price of RotaTeq (~~ezetimibe~~Rotavirus Vaccine, Live Oral, Pentavalent), ~~alleging~~other ~~violations~~than offor resale, from March 3, 2019 to the present. Plaintiff alleges that MSD violated federal and state antitrust laws, asand ~~well~~state asconsumer ~~other~~protection ~~state~~laws. ~~statutory~~Plaintiff ~~and~~alleges ~~common~~that ~~law~~MSD ~~causes~~has ofimplemented ~~action.~~an ~~The~~anticompetitive ~~cases~~vaccine ~~were~~bundling ~~consolidated~~scheme inwhereby aMSD ~~federal~~leverages ~~multidistrict~~its ~~litigation~~alleged ~~(Zetia~~monopoly ~~MDL)~~power ~~before~~in ~~Judge~~certain ~~Rebecca~~pediatric ~~Beach~~vaccine ~~Smith~~markets to maintain its alleged monopoly power in the ~~Eastern~~U.S. ~~District~~market for rotavirus vaccines in order to charge supracompetitive prices for RotaTeq. Plaintiff seeks permanent injunctive relief and unspecified monetary damages on purchases of ~~Virginia~~RotaTeq, trebled, and fees and costs. In ~~April~~May 2023, ~~the~~MSD ~~Merck~~moved ~~Defendants~~to ~~reached~~dismiss ~~settlements~~the ~~with~~complaint. In November 2023, the ~~direct~~court ~~purchaser~~granted in part and ~~retailer~~denied ~~plaintiffs~~in part the motion to dismiss, ~~and~~dismissing aplaintiff’s ~~settlement~~Idaho ~~with~~and ~~the~~Utah ~~indirect~~consumer ~~purchaser~~law ~~class~~claims ~~that~~and ~~the~~allowing ~~court~~all ~~approved~~other inclaims ~~October~~to ~~2023~~proceed.

AsOn ~~previously~~January ~~disclosed~~20, in2026, ~~2020~~plaintiff ~~and~~filed ~~2021,~~a ~~United~~motion ~~HealthCare~~to ~~Services,~~certify ~~Inc~~the proposed class. ~~(United~~On ~~HealthCare)~~February 10, ~~Humana~~2026, ~~Inc.~~Merck ~~(Humana),~~filed ~~Centene~~an ~~Corporation~~opposition ~~and~~to ~~others~~plaintiff’s ~~(Centene),~~motion ~~and~~to ~~Kaiser~~certify ~~Foundation~~the ~~Health~~proposed ~~Plan,~~class ~~Inc.~~and ~~(Kaiser)~~a ~~(collectively,~~motion ~~the~~to ~~Insurer~~exclude ~~Plaintiffs),~~plaintiff’s ~~each~~expert’s ~~filed~~class acertification ~~lawsuit~~opinions. inPlaintiff filed a ~~jurisdiction~~reply ~~outside~~in support of ~~the~~its ~~Eastern~~request ~~District~~to ofcertify ~~Virginia~~the ~~against~~class ~~the~~and ~~Merck~~an ~~Defendants~~opposition ~~and~~to ~~others,~~the ~~making~~motion ~~similar~~to ~~allegations~~exclude ason ~~those~~March ~~made~~17, in2026. ~~the~~On ~~Zetia~~March ~~MDL~~31, as2026, ~~well~~Merck asfiled ~~additional~~a ~~allegations~~reply ~~about~~in ~~Vytorin.~~support ~~These~~of ~~cases~~the ~~were~~motion ~~transferred~~ to ~~the~~exclude ~~Eastern~~plaintiff’s ~~District~~expert’s ofopinions. ~~Virginia~~Merck toalso ~~proceed~~filed ~~with~~a sur-reply to the ~~Zetia~~class ~~MDL~~certification motion.

In December 2023, the U.S. Judicial Panel on Multidistrict Litigation remanded the four Insurer Plaintiff cases to the transferor courts in the Northern District of California (Kaiser), the District of Minnesota (United HealthCare), and the District of New Jersey (Humana and Centene). The Merck Defendants filed motions to dismiss in each of the Insurer Plaintiff cases.

In December 2024, the district court in the District of New Jersey granted in part and denied in part the motions to dismiss in the Humana and Centene cases and, on January 29, 2025, Humana and Centene filed amended complaints. On March 5, 2025, the Merck Defendants filed motions to dismiss the amended complaints. On March 24, 2025, the Merck Defendants filed a third-party complaint against AmerisourceBergen Drug Corp., AmerisourceBergen Corp., and Cencora, Inc., (collectively, Cencora) seeking indemnification and a declaration of rights for Humana’s direct purchaser claims. On June 23, 2025, Cencora moved to dismiss the third-party complaint or, in the alternative, to transfer the third-party action to the Eastern District of Virginia.

On February 25, 2025, the district court in the District of Minnesota granted in part and denied in part the motion to dismiss in the United HealthCare case. On March 11, 2025, the Merck Defendants filed an answer and affirmative defenses in response to United HealthCare’s complaint. On March 24, 2025, the Merck Defendants filed a third-party complaint against Cardinal Health, Inc., Cardinal Health 110, LLC, and Cardinal Health 112, LLC (collectively, Cardinal), seeking indemnification and a declaration of rights for certain of United HealthCare’s direct and indirect purchaser claims. On June 6, 2025, Cardinal filed a motion to dismiss the Merck Defendants’ third-party complaint on forum grounds, or in the alternative, to stay the Merck Defendants’ third-party claims pending arbitration.

On March 18, 2025, the district court in the Northern District of California granted in part and denied in part the motion to dismiss in the Kaiser case. The court granted Kaiser leave to amend its complaint, and Kaiser filed its second amended complaint on April 15, 2025. On May 20, 2025, the Merck Defendants moved to dismiss certain claims in the second amended complaint.

Qui Tam Litigation

As previously disclosed, in June 2012, the U.S. District Court for the Eastern District of Pennsylvania unsealed a complaint that had been filed against the Company under the federal False Claims Act by two former employees alleging, among other things, that the Company defrauded the U.S. government by falsifying data in connection with a clinical study conducted on the mumps component of the Company’s M-M-R II vaccine. The complaint alleged the fraud took place between 1999 and 2001. The U.S. government had the right to participate in and take over the prosecution of this lawsuit but notified the court that it declined to exercise that right. The two former employees pursued the lawsuit without the involvement of the U.S. government. In July 2023, the court denied relators’ motion for summary judgment, granted two of the Company’s motions for summary judgment, and denied the Company’s remaining motions for summary judgment as moot. The court entered judgment in favor of the Company and dismissed relators’ amended complaint in full with prejudice. Relators appealed that decision, and in August 2024, the Third Circuit affirmed the district court’s decision.

In addition, as previously disclosed, two putative class action lawsuits on behalf of direct purchasers of the M‑M‑R II vaccine, which charge that the Company misrepresented the efficacy of the M-M-R II vaccine in violation of federal antitrust laws and various state consumer protection laws, are pending in the Eastern District of Pennsylvania. The court granted the Company’s motion for summary judgment as to plaintiffs’ state law claims and denied the motion as to plaintiffs’ antitrust claim. The Company appealed and, in October 2024, the Third Circuit reversed-in-part the district court’s order and remanded the case with instructions to enter summary judgment for the Company. In November 2024, plaintiffs-appellees filed a petition for rehearing and rehearing en banc and, on February 10, 2025, the court denied the petition. On October 20, 2025, the Supreme Court denied the plaintiffs’ certiorari petition, ending the matter.

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Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Patent Litigation

From time to time, generic and biosimilar manufacturers of pharmaceutical products file abbreviated New Drug Applications (ANDAs) and Biologics License Applications, respectively, with the U.S. Food and Drug Administration (FDA) seeking to market generic and biosimilar forms of the Company’s products prior to the expiration of relevant patents owned by the Company. To protect its patent rights, the Company may file patent infringement lawsuits against such generic and biosimilar companies. Similar lawsuits defending the Company’s patent rights may exist in other countries. The Company intends to vigorously defend its patents, which it believes are valid, against infringement by companies attempting to market products prior to the expiration of such patents. As with any litigation, there can be no assurance of the outcomes, which, if adverse, could result in significantly shortened periods of exclusivity for these products and, with respect to products acquired through acquisitions ~~accounted for as business combinations~~, potentially significant intangible asset impairment charges. In addition to these matters, the Company may be involved in other litigation involving its intellectual property and intellectual property owned or licensed by other companies.

Bridion — As previously disclosed, between January and November 2020, the Company received multiple Paragraph IV Certification Letters under the Hatch-Waxman Act notifying the Company that generic drug companies had filed applications to the FDA seeking pre-patent expiry approval to sell generic versions of Bridion (sugammadex) Injection. In March, April and December 2020, the Company filed patent infringement lawsuits ~~in the U.S. District Courts for the District of New Jersey and the Northern District of West Virginia~~ against those generic companies. ~~All actions in the District of New Jersey were consolidated.~~ The ~~West Virginia case was jointly dismissed with prejudice in August 2022 in favor of proceeding in New Jersey. The remaining~~ defendants in the New Jersey action referred to below stipulated to infringement of the asserted claims and withdrew all remaining claims and defenses other than a defense seeking to shorten the patent term extension (PTE) of the sugammadex patent to December 2022. The U.S. District Court for the District of New Jersey held a one-day trial in December 2022 on this remaining PTE calculation defense.

InAs previously disclosed, in June 2023, the U.S. District Court for the District of New Jersey ruled in Merck’s favor. The court held that Merck’s calculation of PTE for the sugammadex patent covering the compound is not invalid and that the U.S. Patent & Trademark Office correctly granted a full five-year extension. Also in June 2023, the U.S. District Court for the District of New Jersey issued a final judgment prohibiting the FDA from approving any of the pending or tentatively approved generic applications until January 27, 2026, except for any subsequent agreements between defendants and Merck or further order by the court. In July 2023, the defendants filed a notice of appeal with the U.S. Court of Appeals for the Federal Circuit. Oral argument took place on February 4, 2025. On March 13, 2025, the Federal Circuit affirmed the district court’s decision, holding that the patent term extension granted to the sugammadex patent covering Bridion was not invalid and that the patent is entitled to its full five-year patent term extension. The FDA has now granted Bridion six months of pediatric exclusivity.

~~While~~- ~~the~~20 New Jersey action was pending, the Company settled with five generic companies providing that these generic companies can bring their generic versions of Bridion to the market in January 2026 (which were subject to delay by any applicable pediatric exclusivity) or earlier under certain circumstances. The FDA has now granted Bridion six months of pediatric exclusivity. Thus, the Federal Circuit’s decision and these settlements secure Bridion’s exclusivity in the U.S. through July 27, 2026.-

Januvia, Janumet, Janumet XR — As previously disclosed, the FDA granted pediatric exclusivity with respect to Januvia (sitagliptin), Janumet (sitagliptin/metformin HCI), and Janumet XR (sitagliptin and metformin HCl extended-release), which provides a further six months of exclusivity in the U.S. beyond the expiration of all patents listed in the FDA’s Orange Book. Adding this exclusivity to the term of the key patent protection extended exclusivity on these products to January 2023. However, Januvia, Janumet, and Janumet XR contain sitagliptin phosphate monohydrate and the Company has another patent covering certain phosphate salt and polymorphic forms of sitagliptin that expires in May 2027, including pediatric exclusivity (salt/polymorph patent).

As previously disclosed, beginning in 2019, a number of generic drug companies filed ANDAs seeking approval of generic forms of Januvia and Janumet along with Paragraph IV certifications challenging the validity of the salt/polymorph patent. The Company has settled with over two dozen generic companies providing that these generic companies can bring their generic versions of Januvia and Janumet to the market in the U.S. in May 2026 or earlier under certain circumstances, and their generic versions of Janumet XR to the market in July 2026 or earlier under certain circumstances.

In March 2021, the Company filed a patent infringement lawsuit in the U.S. District Court for the District of Delaware against Zydus Worldwide DMCC, Zydus Pharmaceuticals (USA) Inc., and Cadila Healthcare Ltd. (collectively, Zydus). In that lawsuit, the Company alleged infringement of the salt/polymorph patent based on the filing of Zydus’s NDA seeking approval of a form of sitagliptin that is different from than that used in Januvia. In December 2022, the parties reached settlement that included dismissal of the case without prejudice enabling Zydus to seek final approval of a non-automatically substitutable product. In January 2023, the Company received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Zydus filed an ANDA seeking approval of sitagliptin/metformin HCl tablets. In March 2023, the parties reached settlement enabling Zydus to seek final approval of a non-automatically substitutable product containing a different form of sitagliptin than that used in Janumet. In November 2023, the Company received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Zydus filed an ANDA seeking approval of sitagliptin/metformin HCl Extended Release tablets. In January 2024, the parties reached settlement enabling Zydus to seek final approval of a non-automatically substitutable version containing a different form of sitagliptin than that used in Janumet XR.

As a result of these settlement agreements related to the later expiring 2027 salt/polymorph patent directed to the specific sitagliptin salt form of the products, the Company expects that Januvia and Janumet will not lose market exclusivity in

- 24 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Patent & Trademark Office correctly granted a full five-year extension. Also in June 2023, the U.S. ~~until~~District ~~May~~Court ~~2026~~for ~~and~~the ~~Janumet~~District XRof ~~will~~New ~~not~~Jersey ~~lose~~issued ~~market~~a ~~exclusivity~~final injudgment prohibiting the ~~U.S.~~FDA from approving any of the pending or tentatively approved generic applications until ~~July~~January 27, 2026, ~~although~~except ~~Zydus~~for ~~has~~any ~~received~~subsequent ~~FDA~~agreements ~~approval~~between ~~for~~defendants aand ~~non-automatically~~Merck ~~substitutable~~or ~~form~~further oforder ~~sitagliptin~~by ~~that~~the ~~differs~~court. ~~from~~In March 2025, the ~~form~~Federal inCircuit affirmed the ~~Company~~district court’s ~~sitagliptin~~decision, ~~products~~holding that the patent term extension granted to the sugammadex patent covering Bridion was not invalid and that the patent is entitled to its full five-year patent term extension. In addition, the FDA has now granted Bridion six months of pediatric exclusivity.

While the New Jersey action was pending, the Company settled with five generic companies providing that these generic companies can bring their generic versions of Bridion to the market in January 2026 (which were subject to delay by any applicable pediatric exclusivity which has been granted) or earlier under certain circumstances. Thus, the Federal Circuit’s decision and these settlements secure Bridion’s exclusivity in the U.S. through July 27, 2026.

As previously disclosed, beginning in 2019, a number of generic drug companies filed ANDAs seeking approval of generic forms of Januvia and Janumet along with Paragraph IV certifications challenging the validity of the salt/polymorph patent. The Company has settled with over two dozen generic companies providing that these generic companies can bring their generic versions of Januvia and Janumet to the market in the U.S. in May 2026, and their generic versions of Janumet XR to the market in July 2026 or earlier under certain circumstances.

As a result of these settlement agreements related to the later expiring 2027 salt/polymorph patent directed to the specific sitagliptin salt form of the products, Januvia and Janumet will lose market exclusivity in the U.S. in May 2026 and Janumet XR will lose market exclusivity in the U.S. in July 2026, although the FDA has approved a non-automatically substitutable form of sitagliptin that differs from the form in the Company’s sitagliptin products.

In March 2024, the Company received another Paragraph IV Certification Letter under the Hatch-Waxman Act from Azurity Pharmaceuticals, Inc. (Azurity) asserting that a different sitagliptin product subject to its ANDA does not infringe the salt/polymorph patent. In May 2024, Merck filed a civil action in the U.S. District Court of Delaware alleging infringement. The case was dismissed without prejudice in July 2024. Following the dismissal, the Company granted Azurity a covenant not to assert the salt/polymorph patent against the Azurity product that is the subject of such ANDA.

Supplementary Protection Certificates (SPCs) for Janumet expired in April 2023 for the majority of European countries. Prior to expiration, generic companies sought revocation of the Janumet SPCs in a number of European countries. In February 2022, a Finnish court referred certain questions to the Court of Justice of the European Union that could impact the validity of the Janumet SPCs in Europe. A decision rendered in December 2024 provides guidance on points of law and does not directly apply to the Janumet SPCs. Thus, additional proceedings in certain countries where generic companies were prevented from launching products during the SPC period may be necessary to determine whether the SPCs are valid and if not, whether damages are appropriate. Those countries include Belgium, Czech Republic, Finland, and France. If the Janumet SPCs are ultimately upheld, the Company has reserved its rights related to the pursuit of damages for those countries where a generic launched prior to expiry of the Janumet SPC.

In October 2023, the Company filed a patent infringement lawsuit against Sawai Pharmaceuticals Co., Ltd. (Sawai) and Medisa Shinyaku Co., Ltd (collectively, Defendants) in the Tokyo District Court seeking an injunction to stop the manufacture, sale and offer for sale of the Defendants’ sitagliptin dihydrogen phosphate product, while the Company’s patents and patent term extensions are in force. The lawsuit is in response to the Defendants’ application for marketing authorization to sell a generic sitagliptin dihydrogen phosphate product, in the ~~anhydrate~~anhydride form, which was approved in August 2023. Merck asserts that the Defendants’ activity infringes a patent term extension associated with Merck’s patent directed to the sitagliptin compound patent. In January 2026, the Tokyo District Court orally indicated its view that the extended patent covers Sawai’s tablets. Following this, Sawai conceded to all of the Company’s claims; thus, the case was concluded without a written decision. The relevant PTE for Januvia in Japan expired on March 30, 2026.

Keytruda — As previously disclosed, in November 2022, the Company filed a complaint against The Johns Hopkins University (JHU) in the U.S. District Court of Maryland. This action concerns a joint research collaboration between Merck and JHU regarding the use of Keytruda in certain indications. Merck and JHU partnered to design and conduct a clinical study administering Keytruda to cancer patients having tumors that had the genetic biomarker known as microsatellite instability-high (MSI-H) (the Joint Clinical Study). Subsequently JHU obtained a number of U.S. patents specifically relying on the Joint Clinical Study. Merck alleges that JHU breached the collaboration agreement by obtaining issuance of these patents without informing or involving Merck, which were licensed to others, and then trying to enforce these patents against Merck. Merck, therefore, brought an action for breach of contract, declaratory judgment of noninfringement, and promissory estoppel. JHU answered the complaint in April and May 2023, denying Merck’s claims, and counterclaiming for willful infringement of nine issued U.S. patents, including a demand for damages. Between November 30, 2023, and March 13, 2024, the Company filed inter partes review petitions with the ~~United~~U.S. ~~States~~ Patent Office’s Patent Trial and Appeal Board (PTAB), challenging the patentability of all nine patents asserted in the district court. Between June 2024 and October 2024, the PTAB instituted a review of all nine challenged patents. In June 2024, ~~the district court granted Merck’s motion to stay the case in its entirety pending the outcome of the PTAB proceeding instituted in June 2024.~~

~~Between~~- ~~June~~21 and October of 2025, the PTAB issued Final Written Decisions finding all claims of the first six patents challenged unpatentable. JHU has filed notices of appeal to the Federal Circuit Court of Appeals for two of the patents invalidated by the PTAB. Director Review Requests and/or Appeals are still possible for the four additional patents invalidated by the PTAB. The remaining three patents are expected to have Final Written Decisions issued by the PTAB in mid to late November 2025. The district court’s stay is expected to continue until at least the issuance of Final Written Decisions for the three remaining patents.-

Subcutaneous Pembrolizumab — Halozyme, Inc. has publicly alleged that certain patents in its modified hyaluronidase (MDASE) portfolio cover an ingredient in the Company’s subcutaneous pembrolizumab product. In November 2024, the Company began filing a series of post grant review (PGR) petitions before the PTAB alleging that certain patents in the MDASE portfolio are invalid. On June 2, 2025, the PTAB instituted the first petition filed by the Company. Since then, the PTAB also instituted ten additional petitions. Institution decisions on three additional patents in the MDASE portfolio are still pending.

On April 24, 2025, Halozyme, Inc. filed a complaint in the U.S. District Court for the District of New Jersey alleging that the Company’s activities related to subcutaneous pembrolizumab infringe or will infringe 15 patents belonging to the MDASE portfolio, 12 of which are the subject of the Company’s already filed PGR petitions. Although there are three patents that were not and cannot be challenged using the PGR process, the Company believes those patents are invalid and suffer from the same defects as the patents currently being challenged and those patents can be challenged in court proceedings if required.

Between August and September 2025, the Company filed revocation actions against EP Patent No. 2 797 622 (the ‘622 patent) owned by Halozyme, Inc. in the UK, France, Germany and The Netherlands. Halozyme, Inc. counterclaimed for an injunction in the UK under the ‘622 patent as well as an additional patent but have undertaken not to enforce any injunction there until the validity of both patents, which is in dispute, is finally determined. On October 2, 2025, the Company accepted service of a preliminary injunction filed by Halozyme, Inc. under the ‘622 patent in Germany. A preliminary injunction hearing is scheduled to occur on December 4, 2025.

- 25 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

~~Lynparza — As previously disclosed, between December 2022 and November 2024, AstraZeneca Pharmaceuticals LP received Paragraph IV Certification Letters under~~ the ~~Hatch-Waxman~~district ~~Act~~court ~~notifying~~granted ~~AstraZeneca~~Merck’s ~~that~~motion ~~Natco Pharma Limited, Sandoz Inc., Cipla USA, Inc and Cipla Limited (collectively Cipla), and Zydus Pharmaceuticals (USA) Inc. have filed separate applications~~ to ~~the~~stay ~~FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. Between February 2023 and January 2025, AstraZeneca and~~ the ~~Company~~case ~~filed a series of patent infringement lawsuits~~ in ~~the~~its ~~U.S.~~entirety ~~District~~pending ~~Court for~~ the ~~District~~outcome of ~~New Jersey against each generic company asserting a number of Orange-Book listed patents. The filing of~~ the ~~initial~~PTAB ~~infringement~~proceeding ~~suit~~instituted generally stays FDA approval for 30 months from the date of the Paragraph IV notice or until an adverse court decision, if any, whichever may occur earlier. In these cases, however, none of the generic companies are challenging the patent specifically claiming the olaparib compound which expires in ~~September~~June ~~2027~~2024. ~~Thus, the earliest date the FDA can approve any of the currently pending generic applications is September 2027. All cases have been consolidated and a trial is expected in 2026.~~

~~Capvaxive~~As —previously Ondisclosed, ~~September~~between 5,June and November 2025, ~~Pogona,~~the ~~LLC~~PTAB ~~filed~~issued aFinal ~~complaint~~Written inDecisions ~~the~~finding ~~U.S.~~all ~~District~~challenged ~~Court~~claims ~~for~~of the ~~District~~nine ofpatents ~~New~~unpatentable. ~~Jersey~~JHU ~~alleging~~has ~~that~~filed ~~the~~notices ~~Company’s~~of ~~activities~~appeal ~~related~~ to ~~Capvaxive~~the ~~infringe~~Federal ~~U.S.~~Circuit ~~Patent~~Court ~~No.~~of ~~11,058,757~~Appeals. ~~Pogona,~~The ~~LLC~~district ~~is asserting the Company~~court’s ~~infringement~~stay is ~~willful~~expected ~~and~~to iscontinue ~~seeking~~until ~~monetary~~at ~~damages.~~least ~~The~~the ~~Company~~issuance ~~believes~~of the ~~asserted~~Federal ~~patent~~Circuit ~~is invalid and not infringed~~decision.

Subcutaneous Pembrolizumab — As previously disclosed, Halozyme, Inc. (Halozyme) has publicly alleged that certain patents in its modified hyaluronidase (MDASE) portfolio cover an ingredient in the Company’s subcutaneous pembrolizumab product. In November 2024, the Company began filing a series of post grant review (PGR) petitions before the PTAB alleging that certain patents in the MDASE portfolio are invalid. In June 2025, the PTAB instituted the first petition filed by the Company. Since then, the PTAB also instituted 13 additional petitions. An institution decision on one additional patent in the MDASE portfolio is still pending.

In April 2025, Halozyme filed a complaint in the U.S. District Court for the District of New Jersey alleging that the Company’s activities related to subcutaneous pembrolizumab infringe or will infringe 15 patents belonging to the MDASE portfolio, 12 of which are the subject of the Company’s already filed PGR petitions. The Company believes the three patents not challenged via PGR petitions are invalid and suffer from at least the same defects as the patents currently being challenged by the PGR process. In March 2026, the Company filed inter partes review (IPR) petitions against those three patents. The Company expects that the U.S. Patent and Trademark Office will issue an institution decision on these IPR petitions by late-September 2026.

Between August and September 2025, the Company filed revocation actions against EP Patent No. 2 797 622 (the ‘622 patent) owned by Halozyme in the UK, France, Germany and The Netherlands. Halozyme counterclaimed for an injunction in the UK under the ‘622 patent as well as an additional patent but have undertaken not to enforce any injunction there until the validity of both patents, which is in dispute, is finally determined. In October 2025, the Company accepted service of a preliminary injunction filed by Halozyme under the ‘622 patent in Germany. Following a one day hearing in December 2025, a preliminary injunction was awarded against the Company, prohibiting sales in Germany. The Company has appealed the preliminary injunction decision and expects a decision on the appeal in the second or third quarter of 2026. In the Dutch action, in February 2026, Halozyme counterclaimed for infringement including also Belgium, Denmark, France, Ireland, Italy, Sweden and Switzerland. The Dutch action will be heard at the end of July 2026 with a decision expected within three months thereof.

Lenvima — As previously disclosed, between 2019 and 2024, Eisai Inc (Eisai) received Paragraph IV Certification Letters under the Hatch-Waxman Act, providing notice that Sun Pharmaceuticals (Sun), Shilpa Medicare Ltd. (Shilpa), Dr. Reddy’s Laboratories (DRL), and Torrent Pharmaceuticals (Torrent) filed separate applications to the FDA seeking pre-patent expiry approval to sell generic versions of Lenvima (lenvatinib) tablets. Between 2019 and 2024, Eisai and the Company filed a series of patent infringement lawsuits in the U.S. District Court for the District of New Jersey against each generic company asserting several Orange-Book listed patents. The Lenvima compound patent expired in April 2026 (including pediatric exclusivity) and was not challenged. Eisai and the Company settled with Sun, DRL, and Torrent regarding the remaining asserted patents covering Lenvima. Eisai has announced publicly, these generic companies can bring their generic versions of Lenvima to the market in the U.S. in July 2030 or earlier under certain circumstances. In May 2025, Eisai and the Company received a favorable trial decision against Shilpa from the U.S. District Court for the District of New Jersey. As a result of the decision, Shilpa is unable to receive approval from the FDA to sell its generic version of Lenvima until February 2036. Shilpa has appealed the district court’s decision to the U.S. Court of Appeals for the Federal Circuit, and the appeal is currently pending.

Lynparza — As previously disclosed, between December 2022 and November 2024, AstraZeneca Pharmaceuticals LP received Paragraph IV Certification Letters under the Hatch-Waxman Act notifying AstraZeneca that Natco Pharma Limited, Sandoz Inc., Cipla USA, Inc and Cipla Limited (collectively, Cipla), and Zydus Pharmaceuticals (USA) Inc. have filed separate applications to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. Between February 2023 and January 2025, AstraZeneca and the Company filed a series of patent infringement lawsuits in the U.S. District Court for the District of New Jersey against each generic company asserting a number of Orange-Book listed patents. The filing of the initial infringement suit generally stays FDA approval for 30 months from the date of the Paragraph IV notice or until an adverse court decision, if any, whichever may occur earlier. In these cases, however, none of the generic companies are challenging the patent specifically claiming the olaparib compound which expires in September 2027. Thus, the earliest date the FDA can approve any of the currently pending generic applications is September 2027. All cases have been consolidated and a trial is now expected in early 2027.

Capvaxive — As previously disclosed, in September 2025, Pogona, LLC filed a complaint in the U.S. District Court for the District of New Jersey alleging that the Company’s activities related to Capvaxive infringe U.S. Patent No. 11,058,757 (‘757 patent). Pogona, LLC is asserting the Company’s infringement is willful and is seeking monetary damages. The Company believes the asserted patent is invalid and not infringed. On January 26, 2026, the Company filed an inter-partes review petition with the U.S. Patent Trial and Appeal Board, challenging the validity of Pogona’s ‘757 patent, which is currently pending.

Other Litigation

There are various other pending legal proceedings involving the Company, principally product liability and intellectual property lawsuits. While it is not feasible to predict the outcome of such proceedings, in the opinion of the Company, either the likelihood of loss is remote or any reasonably possible loss associated with the resolution of such proceedings is not expected to be material to the Company’s financial condition, results of operations or cash flows either individually or in the aggregate.

~~Legal~~- ~~Defense~~22 ~~Reserves~~-

Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable. Some of the significant factors considered in the review of these legal defense reserves are as follows: the actual costs incurred by the Company; the development of the Company’s legal defense strategy and structure in light of the scope of its litigation; the number of cases being brought against the Company; the costs and outcomes of completed trials; and the most current information regarding anticipated timing, progression, and related costs of pre-trial activities and trials in the associated litigation. The amount of legal defense reserves as of September 30, 2025 and December 31, 2024 of approximately $220 million and $225 million, respectively, represents the Company’s best estimate of the minimum amount of defense costs to be incurred in connection with its outstanding litigation; however, events such as additional trials and other events that could arise in the course of its litigation could affect the ultimate amount of legal defense costs to be incurred by the Company. The Company will continue to monitor its legal defense costs and review the adequacy of the associated reserves and may determine to increase the reserves at any time in the future if, based upon the factors set forth, it believes it would be appropriate to do so.

- 26 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Legal Defense Reserves

Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable. Some of the significant factors considered in the review of these legal defense reserves are as follows: the actual costs incurred by the Company; the development of the Company’s legal defense strategy and structure in light of the scope of its litigation; the number of cases being brought against the Company; the costs and outcomes of completed trials; and the most current information regarding anticipated timing, progression, and related costs of pre-trial activities and trials in the associated litigation. The amount of legal defense reserves as of March 31, 2026 and December 31, 2025 of approximately $270 million and $245 million, respectively, represents the Company’s best estimate of the minimum amount of defense costs to be incurred in connection with its outstanding litigation; however, events such as additional trials and other events that could arise in the course of its litigation could affect the ultimate amount of legal defense costs to be incurred by the Company. The Company will continue to monitor its legal defense costs and review the adequacy of the associated reserves and may determine to increase the reserves at any time in the future if, based upon the factors set forth, it believes it would be appropriate to do so.

9. Equity

	Three Months Ended September 30,
	Three Months Ended March 31,
	Common Stock			OtherPaid-InCapital		RetainedEarnings		AccumulatedOtherComprehensiveLoss		Treasury Stock			Non-controllingInterests		Total
($ and shares in millions except per share amounts)	Shares	Par Value								Shares	Cost
Balance at July 1, 2024	3,577	$	1,788	$	44,362	$	60,187	$	(5,361)	1,041	$	(57,394)	$	66	$	43,648
Balance at January 1, 2025	3,577	$	1,788	$	44,704	$	63,069	$	(4,945)	1,049	$	(58,303)	$	59	$	46,372
Net income attributable to Merck & Co., Inc.	—	—		—		35,~~157~~079		—		—	—		—		35,~~157~~079
Other comprehensive loss, net of taxes	—	—		—		—		(1020)		—	—		—		(1020)
Cash dividends declared on common stock ($0.77 per share)	—	—		—		(1,960)		—		—	—		—		(1,960)
Cash dividends declared on common stock ($0.81 per share)	—	—		—		(2,051)		—		—	—		—		(2,051)
Treasury stock shares purchased	—	—		—		—		—		413	(~~444~~1,164)		—		(~~444~~1,164)
Share-based compensation plans and other	—	—		~~168~~112		—		—		—(1)	966		—		~~177~~178
Net income attributable to noncontrolling interests	—	—		—		—		—		—	—		46		46
Distributions attributable to noncontrolling interests	—	—		—		—		—		—	—		(12)		(12)
Balance at March 31, 2025	3,577	$	1,788	$	44,816	$	66,097	$	(4,965)	1,061	$	(59,401)	$	65	$	48,400
Balance at September 30, 2024	3,577	$	1,788	$	44,530	$	61,384	$	(5,371)	1,045	$	(57,829)	$	58	$	44,560
Balance at January 1, 2026	3,577	$	1,788	$	45,029	$	73,075	$	(4,287)	1,102	$	(62,999)	$	56	$	52,662
Balance at July 1, 2025	3,577	$	1,788	$	44,644	$	68,477	$	(5,421)	1,074	$	(60,495)	$	67	$	49,060
Net loss attributable to Merck & Co., Inc.	—	—		—		(4,240)		—		—	—		—		(4,240)
Net income attributable to Merck & Co., Inc.	—	—		—		5,785		—		—	—		—		5,785
Other comprehensive income, net of taxes	—	—		—		—		227		—	—		—		227
Other comprehensive income, net of taxes	—	—		—		—		219		—	—		—		219
Cash dividends declared on common stock ($0.85 per share)	—	—		—		(2,114)		—		—	—		—		(2,114)
Cash dividends declared on common stock ($0.81 per share)	—	—		—		(2,031)		—		—	—		—		(2,031)
Treasury stock shares purchased	—	—		—		—		—		8	(925)		—		(925)
Treasury stock shares purchased	—	—		—		—		—		16	(1,324)		—		(1,324)
Share-based compensation plans and other	—	—		147		—		—		(3)	177		—		324
Share-based compensation plans and other	—	—		188		—		—		—	20		—		208
Net loss attributable to noncontrolling interests	—	—		—		—		—		—	—		(3)		(3)
Net income attributable to noncontrolling interests	—	—		—		—		—		—	—		2		2
Balance at March 31, 2026	3,577	$	1,788	$	45,176	$	66,721	$	(4,060)	1,107	$	(63,747)	$	53	$	45,931
Distributions attributable to noncontrolling interests	—	—		—		—		—		—	—		(12)		(12)
Balance at September 30, 2025	3,577	$	1,788	$	44,832	$	72,231	$	(5,202)	1,090	$	(61,799)	$	57	$	51,907

	Nine Months Ended September 30,
	Common Stock			OtherPaid-InCapital		RetainedEarnings		AccumulatedOtherComprehensiveLoss		Treasury Stock			Non-controllingInterests		Total
($ and shares in millions except per share amounts)	Shares	Par Value								Shares	Cost
Balance at January 1, 2024	3,577	$	1,788	$	44,509	$	53,895	$	(5,161)	1,045	$	(57,450)	$	54	$	37,635
Net income attributable to Merck & Co., Inc.	—	—		—		13,374		—		—	—		—		13,374
Other comprehensive loss, net of taxes	—	—		—		—		(210)		—	—		—		(210)
Cash dividends declared on common stock ($2.31 per share)	—	—		—		(5,885)		—		—	—		—		(5,885)
Treasury stock shares purchased	—	—		—		—		—		7	(817)		—		(817)
Share-based compensation plans and other	—	—		21		—		—		(7)	438		1		460
Net income attributable to noncontrolling interests	—	—		—		—		—		—	—		15		15
Distributions attributable to noncontrolling interests	—	—		—		—		—		—	—		(12)		(12)
Balance at September 30, 2024	3,577	$	1,788	$	44,530	$	61,384	$	(5,371)	1,045	$	(57,829)	$	58	$	44,560
Balance at January 1, 2025	3,577	$	1,788	$	44,704	$	63,069	$	(4,945)	1,049	$	(58,303)	$	59	$	46,372
Net income attributable to Merck & Co., Inc.	—	—		—		15,291		—		—	—		—		15,291
Other comprehensive loss, net of taxes	—	—		—		—		(257)		—	—		—		(257)
Cash dividends declared on common stock ($2.43 per share)	—	—		—		(6,129)		—		—	—		—		(6,129)
Treasury stock shares purchased	—	—		—		—		—		46	(3,832)		—		(3,832)
Share-based compensation plans and other	—	—		128		—		—		(5)	336		—		464
Net income attributable to noncontrolling interests	—	—		—		—		—		—	—		10		10
Distributions attributable to noncontrolling interests	—	—		—		—		—		—	—		(12)		(12)
Balance at September 30, 2025	3,577	$	1,788	$	44,832	$	72,231	$	(5,202)	1,090	$	(61,799)	$	57	$	51,907

- 27 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

10. Pension and Other Postretirement Benefit Plans

The Company has defined benefit pension plans covering eligible employees in the U.S. and in certain of its international subsidiaries. The net periodic benefit cost (credit) of such plans consisted of the following components:

	Three Months EndedSeptember 30,								Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
	2025				2024				2025				2024
	2026				2025
($ in millions)	U.S.		International		U.S.		International		~~U.S.~~		~~International~~		~~U.S.~~		~~International~~
Service cost	$	~~100~~98	$	5748	$	~~100~~89	$	6054	$	~~279~~	$	~~171~~	$	~~273~~	$	~~182~~
Interest cost	~~143~~145		7881		~~134~~141		7471		~~425~~		~~225~~		~~403~~		~~220~~
Expected return on plan assets	(~~210~~207)		(~~159~~161)		(~~206~~210)		(~~139~~143)		~~(630)~~		~~(454)~~		~~(621)~~		~~(416)~~
Amortization of unrecognized prior service credit	—		(4)		—		(34)		—		~~(12)~~		—		~~(10)~~
Net loss amortization	16		3		12		1		42		8		30		4
Net loss (gain) amortization	27		(1)		13		3
Termination benefits	—3		—15		1—		—		1		—		5		—
Curtailments	9		(16)		—		—		8		(16)		—		—
	$	66	$	(22)	$	33	$	(19)
	$	58	$	(41)	$	41	$	(7)	$	125	$	(78)	$	90	$	(20)

- 23 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The Company provides medical benefits, principally to its eligible U.S. retirees and similar benefits to their dependents, through its other postretirement benefit plans. The net credit of such plans consisted of the following components:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
	Three Months EndedMarch 31,
($ in millions)	~~2025~~2026		~~2024~~2025		~~2025~~		~~2024~~
Service cost	$	911	$	710	$	29	$	23
Interest cost	1516		1416		46		42
Expected return on plan assets	(1314)		(2014)		~~(39)~~		~~(60)~~
Amortization of unrecognized prior service credit	(109)		(1110)		~~(30)~~		~~(32)~~
Net gain amortization	(128)		(1410)		~~(33)~~		~~(38)~~
	$	(11)	$	(24)	$	(27)	$	(65)
Terminations benefits	1		—
	$	(3)	$	(8)

In connection with restructuring actions (see Note 4), termination charges were recorded on pension plans related to expanded eligibility for certain employees exiting Merck. ~~Also, in connection with these restructuring activities, curtailments were recorded on certain pension plans.~~

The components of net periodic benefit cost (credit) other than the service cost component are included in Other (income) expense, net (see Note 11), with the exception of certain amounts for termination benefits which are recorded in Restructuring costs if the event giving rise to the termination benefits related to restructuring actions.

11. Other (Income) Expense, Net

Other (income) expense, net, consisted of:

Three Months EndedSeptember 30,

Nine Months EndedSeptember 30,

Three Months EndedMarch 31,

($ in millions)

~~2025~~2026

~~2024~~2025

~~2025~~

~~2024~~

Interest income

(9635)

(~~127~~109)

~~(274)~~

~~(269)~~

Interest expense

~~327~~479

~~330~~313

~~946~~

~~943~~

Exchange losses

5638

3390

~~224~~

~~177~~

(Income) loss from investments in equity securities, net (1)

(373)

(563)

(169)

Income from investments in equity securities, net (1)

(168)

(90)

Net periodic defined benefit plan (credit) cost other than service cost

(~~152~~134)

(~~157~~148)

~~(452)~~

~~(476)~~

Other, net

—(42)

(~~272~~91)

~~(162)~~

~~(357)~~

~~(238)~~138

(~~162~~35)

~~(281)~~

~~(151)~~

(1) Includes net realized and unrealized gains and losses from investments in equity securities either owned directly or through ownership interests in investment funds. Unrealized gains and losses from investments that are owned directly are determined at the end of the reporting period, while gains and losses from ownership interests in investment funds are accounted for on a one quarter lag.

~~Other,~~Interest ~~net~~paid ~~(as~~for ~~reflected in~~ the ~~table~~three ~~above)~~months inended ~~the~~March 31, ~~third~~2026 ~~quarter~~ and ~~first~~2025 ~~nine~~was ~~months of 2024 includes~~ $~~170~~ 342 million ~~of income related to the expansion of the existing development~~ and ~~commercialization~~$233 ~~agreement~~million, ~~with Daiichi Sankyo (see Note 3)~~respectively.

Interest paid for the nine months ended September 30, 2025 and 2024 was $849 million and $822 million, respectively.

- 28 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

12. Income Taxes

The income tax provision of $709 million for the first quarter of 2026 on a pretax loss of $3.5 billion, resulted in an effective income tax ~~rates~~rate of 14(20.21)%. ~~and~~The 13first quarter 2026 effective income tax rate reflects a 33.3%1 percentage point unfavorable impact of the charge for the ~~third~~acquisition ~~quarter~~of Cidara, which had no tax benefit, partially offset by the favorable impacts of jurisdictional mix of income and ~~first~~expense. ~~nine~~The ~~months~~effective income tax rate of ~~2025,~~13.9% ~~respectively,~~for ~~reflect~~the first quarter of 2025 reflects the favorable impacts of ~~geographical~~jurisdictional mix of income and expense, as well as certain discrete items.

The ~~effective~~Internal ~~income~~Revenue ~~tax~~Service ~~rate~~(IRS) ofis ~~22.7%~~currently ~~for~~conducting examinations of the ~~third~~Company’s ~~quarter~~tax ofreturns ~~2024~~for ~~reflects~~the ayears ~~7.2~~2017 ~~percentage~~and ~~point~~2018, ~~combined~~including ~~unfavorable~~the ~~impact~~one-time oftransition ~~charges~~tax ~~related~~enacted tounder the ~~acquisitions~~Tax Cuts and Jobs Act of ~~EyeBio~~2017. ~~and~~In ~~MK-1045~~April 2025, ~~which~~Merck ~~had~~received ~~minimal~~Notices ~~tax~~of ~~benefits.~~Proposed ~~The~~Adjustment ~~effective~~(NOPAs) ~~income~~that ~~tax~~would ~~rate~~increase ofthe ~~15.1%~~amount ~~for~~of the ~~first~~one-time ~~nine~~transition ~~months~~tax on certain undistributed earnings of ~~2024~~foreign ~~reflects~~subsidiaries aby 2.approximately $1.3 billion. ~~percentage~~In ~~point~~addition, ~~combined~~the ~~unfavorable~~NOPAs ~~impact~~included penalties of ~~charges~~approximately ~~related~~$260 million. toThese ~~the~~amounts ~~acquisitions~~are exclusive of ~~Harpoon,~~any ~~EyeBio~~interest ~~and~~that ~~MK-1045,~~may ~~which~~be ~~had~~due. ~~minimal~~The ~~tax~~Company ~~benefits.~~disagrees ~~The~~with ~~effective~~the ~~income~~proposed ~~tax~~adjustments ~~rate~~and ~~for~~will vigorously contest the ~~first~~NOPAs ~~nine~~through ~~months~~all ofavailable ~~2024~~administrative ~~also~~and, ~~reflects~~if anecessary, 1judicial proceedings.6 ~~percentage~~It ~~point~~may ~~favorable~~take ~~impact~~a ~~due~~number of years to areach ~~$259 million~~resolution ~~reduction~~of inthis ~~reserves~~matter. ~~for~~If ~~unrecognized~~the ~~income~~Company ~~tax~~is ~~benefits~~ultimately ~~resulting~~unsuccessful ~~from~~in defending its position, the ~~expiration~~impact incould ~~June~~be ~~2024~~material ofto ~~the~~its financial statements. The statute of limitations for assessments ~~related~~with respect to the 2019 and 2020 federal tax return ~~year~~years expired in June 2024 and October 2024, respectively. The IRS is also currently conducting examinations of the Company’s tax returns for the years 2021 and 2022. In addition, various state and foreign tax examinations are in progress.

While many jurisdictions in which Merck operates have adopted the global minimum tax provision of the Organization for Economic Cooperation and Development (OECD) Pillar 2, effective for tax years beginning in January 2024, it resulted in a minimal impact to the Company’s 2024 effective income tax rate due to the accounting for the tax effects of intercompany transactions. In addition, in July 2025, H.R.1 - ~~One~~24 ~~Big Beautiful Bill Act (OBBBA) was enacted into law, which had an immaterial impact to the effective tax rates for the third quarter and first nine months of 2025.~~ -

The Internal Revenue Service (IRS) is currently conducting examinations of the Company’s tax returns for the years 2017 and 2018, including the one-time transition tax enacted under the Tax Cuts and Jobs Act of 2017 (TCJA). In April 2025, Merck received Notices of Proposed Adjustment (NOPAs) that would increase the amount of the one-time transition tax on certain undistributed earnings of foreign subsidiaries by approximately $1.3 billion. In addition, the NOPAs included penalties of approximately $260 million. These amounts are exclusive of any interest that may be due. The Company disagrees with the proposed adjustments and will vigorously contest the NOPAs through all available administrative and, if necessary, judicial proceedings. It is expected to take a number of years to reach resolution of this matter. If the Company is ultimately unsuccessful in defending its position, the impact could be material to its financial statements. The statute of limitations for assessments with respect to the 2019 and 2020 federal tax return years expired in June 2024 (as noted above) and October 2024, respectively. The IRS is also currently conducting examinations of the Company’s tax returns for the years 2021 and 2022. In addition, various state and foreign examinations are in progress.

13. Earnings Per Share

The calculations of earnings per share are as follows:

	Three Months EndedSeptember 30,				Nine Months EndedSeptember 30,
($ and shares in millions except per share amounts)	2025		2024		2025		2024
Net Income Attributable to Merck & Co., Inc.	$	5,785	$	3,157	$	15,291	$	13,374
Average common shares outstanding	2,495		2,534		2,509		2,534
Common shares issuable (1)	3		7		5		9
Average common shares outstanding assuming dilution	2,498		2,541		2,514		2,543
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders	$	2.32	$	1.25	$	6.09	$	5.28
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders	$	2.32	$	1.24	$	6.08	$	5.26

(1) Issuable primarily under share-based compensation plans.

For the third quarter of 2025 and 2024, 15 million and 7 million, respectively, and for the first nine months of 2025 and 2024, 12 million and 6 million, respectively, of common shares issuable under share-based compensation plans were excluded from the computations of earnings per common share assuming dilution because the effect would have been antidilutive.

- 29 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

13. (Loss) Earnings Per Share

The calculations of (loss) earnings per share are as follows:


	Three Months Ended March 31,
($ and shares in millions except per share amounts)	2026		2025
Net (Loss) Income Attributable to Merck & Co., Inc.	$	(4,240)	$	5,079
Average common shares outstanding	2,472		2,523
Common shares issuable (1)	—		8
Average common shares outstanding assuming dilution	2,472		2,531
Basic (Loss) Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders	$	(1.72)	$	2.01
(Loss) Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders	$	(1.72)	$	2.01

(1) Issuable primarily under share-based compensation plans.

The Company recorded a net loss for the first quarter of 2026; therefore, no potential dilutive common shares were used in the computation of loss per common share assuming dilution because the effect would have been antidilutive. For the first quarter of 2025, 10 million of common shares issuable under share-based compensation plans were excluded from the computation of earnings per common share assuming dilution because the effect would have been antidilutive.

14. Other Comprehensive Income (Loss)

Changes in each component of other comprehensive income (loss) are as follows:

	Three Months Ended September 30,
	Three Months Ended March 31,
($ in millions)	Derivatives			EmployeeBenefitPlans			Foreign CurrencyTranslationAdjustment		Accumulated OtherComprehensiveLoss
Balance July 1, 2024, net of taxes	$	173		$	(2,808)		$	(2,726)	$	(5,361)
Balance January 1, 2025, net of taxes	$	242		$	(2,327)		$	(2,860)	$	(4,945)
Other comprehensive income (loss) before reclassification adjustments, pretax	(~~325~~201)			—(1)			~~279~~200		(462)
Tax	6842			~~(3)~~—			2015		8557
Other comprehensive income (loss) before reclassification adjustments, net of taxes	(~~257~~159)			(31)			~~299~~215		3955
Reclassification adjustments, pretax	(4973)		(1)	(1410)		(2)	—		(6383)
Tax	1015			4(7)			—		148
Reclassification adjustments, net of taxes	(3958)			(1017)			—		(4975)
Other comprehensive income (loss), net of taxes	(~~296~~217)			(1318)			~~299~~215		(1020)
Balance September 30, 2024, net of taxes	$	(123)		$	(2,821)		$	(2,427)	$	(5,371)
Balance March 31, 2025, net of taxes	$	25		$	(2,345)		$	(2,645)	$	(4,965)
Balance July 1, 2025, net of taxes	$	(385)		$	(2,353)		$	(2,683)	$	(5,421)
Balance January 1, 2026, net of taxes	$	(105)		$	(1,499)		$	(2,683)	$	(4,287)
Other comprehensive income (loss) before reclassification adjustments, pretax	~~113~~168			931			~~(64)~~15		~~142~~184
Tax	(2435)			1			39(9)		16(43)
Other comprehensive income (loss) before reclassification adjustments, net of taxes	89133			942			~~(25)~~6		~~158~~141
Reclassification adjustments, pretax	~~103~~105		(1)	~~(22)~~5		(2)	—		81110
Tax	(22)			(2)			—		(2024)
Reclassification adjustments, net of taxes	8183			~~(20)~~3			—		6186
Other comprehensive income (loss), net of taxes	~~170~~216			745			~~(25)~~6		~~219~~227
Balance September 30, 2025, net of taxes	$	(215)		$	(2,279)		$	(2,708)	$	(5,202)
Balance March 31, 2026, net of taxes	$	111		$	(1,494)		$	(2,677)	$	(4,060)

	Nine Months Ended September 30,
($ in millions)	Derivatives			EmployeeBenefitPlans			Foreign CurrencyTranslationAdjustment		Accumulated OtherComprehensiveLoss
Balance January 1, 2024, net of taxes	$	(24)		$	(2,793)		$	(2,344)	$	(5,161)
Other comprehensive income (loss) before reclassification adjustments, pretax	22			6			(103)		(75)
Tax	(5)			(5)			—		(10)
Other comprehensive income (loss) before reclassification adjustments, net of taxes	17			1			(103)		(85)
Reclassification adjustments, pretax	(147)		(1)	(44)		(2)	20		(171)
Tax	31			15			—		46
Reclassification adjustments, net of taxes	(116)			(29)			20		(125)
Other comprehensive income (loss), net of taxes	(99)			(28)			(83)		(210)
Balance September 30, 2024, net of taxes	$	(123)		$	(2,821)		$	(2,427)	$	(5,371)
Balance January 1, 2025, net of taxes	$	242		$	(2,327)		$	(2,860)	$	(4,945)
Other comprehensive income (loss) before reclassification adjustments, pretax	(630)			91			270		(269)
Tax	132			—			(118)		14
Other comprehensive income (loss) before reclassification adjustments, net of taxes	(498)			91			152		(255)
Reclassification adjustments, pretax	52		(1)	(40)		(2)	—		12
Tax	(11)			(3)			—		(14)
Reclassification adjustments, net of taxes	41			(43)			—		(2)
Other comprehensive income (loss), net of taxes	(457)			48			152		(257)
Balance September 30, 2025, net of taxes	$	(215)		$	(2,279)		$	(2,708)	$	(5,202)

(1) Primarily relates to foreign currency cash flow hedges that were reclassified from AOCL to Sales.

(2) Includes net amortization of prior service cost, actuarial gains and losses, settlements and curtailments included in net periodic benefit cost (see Note 10).

~~- 30 -~~

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

15. Segment Reporting

The Company’s operations are principally managed on a product basis and include two operating segments, Pharmaceutical and Animal Health, both of which are reportable segments.

The Pharmaceutical segment includes human health pharmaceutical and vaccine products. Human health pharmaceutical products consist of therapeutic and preventive agents, generally sold by prescription, for the treatment of human disorders. The Company sells these human health pharmaceutical products primarily to drug wholesalers and retailers, hospitals, government agencies and managed health care providers such as health maintenance organizations, pharmacy benefit managers and other institutions. Human health vaccine products consist of preventive pediatric, adolescent and adult vaccines. The Company sells these human health vaccines primarily to physicians, wholesalers, distributors and government entities. A large component of pediatric and adolescent vaccine sales are made to the U.S. Centers for Disease Control and Prevention Vaccines for Children program, which is funded by the U.S. government. Additionally, the Company sells vaccines to the Federal government for placement into vaccine stockpiles.

~~The~~- ~~Animal~~25 Health segment discovers, develops, manufactures and markets a wide range of veterinary pharmaceutical and vaccine products, as well as health management solutions and services, for the prevention, treatment and control of disease in all major livestock and companion animal species. The Company also offers an extensive suite of digitally connected identification, traceability and monitoring products. The Company sells its products to veterinarians, distributors, animal producers, farmers and pet owners.-

- 31 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

The Company sells these human health vaccines primarily to physicians, wholesalers, distributors and government entities. A large component of pediatric and adolescent vaccine sales are made to the U.S. Centers for Disease Control and Prevention Vaccines for Children program, which is funded by the U.S. government. Additionally, the Company sells vaccines to the Federal government for placement into vaccine stockpiles.

The Animal Health segment discovers, develops, manufactures and markets a wide range of veterinary pharmaceutical and vaccine products, as well as health management solutions and services, for the prevention, treatment and control of disease in all major livestock and companion animal species. The Company also offers an extensive suite of digitally connected identification, traceability and monitoring products. The Company sells its products to veterinarians, distributors, animal producers, farmers and pet owners.

Sales of the Company’s products were as follows:

	Three Months Ended September 30,												Nine Months Ended September 30,
	Three Months Ended March 31,
	2025						2024						2025						2024
	2026						2025
($ in millions)	U.S.		Int’l		Total		U.S.		Int’l		Total		~~U.S.~~		~~Int’l~~		~~Total~~		~~U.S.~~		~~Int’l~~		~~Total~~
Pharmaceutical:
Oncology
Keytruda	$	4,~~879~~599	$	3,~~263~~307	$	87,~~142~~906	$	4,~~500~~308	$	2,~~929~~897	$	7,~~429~~205	$	~~13,936~~	$	~~9,367~~	$	~~23,303~~	$	~~13,031~~	$	~~8,614~~	$	~~21,646~~
Alliance revenue-Lynparza (1)	184		195		379		161		177		337		503		558		1,061		449		498		947
Keytruda Qlex	106		21		128		—		—		—
Alliance revenue-Lenvima (1)	177		81		258		173		78		251		545		236		781		523		233		755
Alliance revenue-Lynparza (1)	149		192		341		145		168		312
Welireg	161		35		196		127		12		139		422		74		496		320		29		349
Alliance revenue-Lenvima (1)	176		80		256		186		72		258
Alliance revenue-Reblozyl (2)	111		25		136		82		18		100		299		62		361		215		45		261
Welireg	152		47		199		123		15		137
Alliance revenue-Reblozyl (2)	128		20		148		101		18		119
Vaccines
Gardasil/Gardasil 9	~~1,154~~485		~~595~~585		1,~~749~~069		~~1,020~~536		~~1,285~~790		21,~~306~~327		~~2,235~~		~~1,967~~		~~4,202~~		~~2,045~~		~~4,988~~		~~7,032~~
ProQuad/M-M-R II/Varivax	~~554~~409		~~130~~129		~~684~~538		~~572~~423		~~131~~116		~~703~~539		~~1,457~~		~~374~~		~~1,832~~		~~1,500~~		~~391~~		~~1,891~~
Vaxneuvance	134		91		226		137		103		239		409		276		685		397		251		647
RotaTeq	165		42		206		164		64		228
RotaTeq	141		63		204		131		62		193		366		187		554		388		185		572
Vaxneuvance	123		78		202		139		92		230
Capvaxive	~~238~~118		723		~~244~~142		47106		—1		47107		~~473~~		8		~~480~~		47		—		47
Pneumovax 23	10		35		45		19		49		68		13		111		124		36		152		188
Cardiometabolic and Respiratory
Hospital Acute Care
Winrevair	477		48		525		268		12		280
Bridion	392		47		439		339		81		420		1,181		161		1,341		1,020		296		1,315
Ohtuvayre	131		—		131		—		—		—
Prevymis	128		138		266		101		107		208		345		357		702		265		305		570
Alliance revenue-Adempas/Verquvo (3)	109		—		109		97		9		106
Zerbaxa	49		32		81		39		26		64		136		89		225		106		77		182
Adempas	—		78		78		—		68		68
Dificid	30		13		43		83		13		96		185		37		222		231		30		261
Infectious Diseases
Cardiovascular
Bridion	427		45		472		378		63		441
Winrevair	335		25		360		147		3		149		926		49		976		216		3		219
Prevymis	135		138		272		102		106		208
Alliance revenue-Adempas/Verquvo (3)	103		8		112		96		7		102		308		32		340		283		22		306
Zerbaxa	52		30		82		42		28		70
Adempas	—		82		82		—		72		72		—		229		229		—		214		214
Delstrigo	10		65		75		15		52		67
Virology
Isentress/Isentress HD	35		24		59		51		39		90
Lagevrio	24		114		138		84		299		383		90		233		323		144		699		843
Dificid	24		10		34		72		11		83
Isentress/Isentress HD	44		37		82		54		48		102		144		114		258		147		155		302
Lagevrio	16		12		28		35		67		102
Delstrigo	13		64		77		15		50		65		42		185		228		42		139		180
Pifeltro	29		14		43		31		12		42		86		43		128		86		37		123
Neuroscience
Belsomra	28		19		47		20		58		78		59		77		137		53		124		177
Immunology
Simponi	—		—		—		—		189		189		—		—		—		—		545		545
Remicade	—		—		—		—		41		41		—		—		—		—		115		115
Diabetes
Januvia	~~258~~252		~~124~~116		~~382~~367		67344		~~211~~204		~~278~~549		~~819~~		~~483~~		~~1,302~~		~~428~~		~~674~~		~~1,102~~
Janumet	7868		~~165~~139		~~243~~207		1565		~~190~~182		~~204~~247		~~210~~		~~530~~		~~741~~		70		~~610~~		~~679~~
Other pharmaceutical (4)	~~239~~166		~~716~~608		~~953~~775		~~167~~227		~~466~~637		~~638~~865		~~558~~		~~1,713~~		~~2,268~~		~~521~~		~~1,364~~		~~1,890~~
Total Pharmaceutical segment sales	98,~~493~~512		65,~~118~~837		1514,~~611~~349		87,~~227~~927		65,~~717~~711		1413,~~943~~638		~~25,747~~		~~17,552~~		~~43,299~~		~~22,563~~		~~20,795~~		~~43,358~~
Animal Health:
Livestock	~~213~~211		~~811~~853		1,~~023~~064		194		~~692~~730		~~886~~924		~~598~~		~~2,312~~		~~2,909~~		~~529~~		~~2,044~~		~~2,573~~
Companion Animal	~~291~~308		~~301~~419		~~592~~727		~~293~~308		~~307~~356		~~601~~664		~~907~~		~~1,033~~		~~1,940~~		~~888~~		~~1,019~~		~~1,907~~
Total Animal Health segment sales	~~504~~519		1,~~112~~272		1,~~615~~791		~~487~~502		~~999~~1,086		1,~~487~~588		~~1,505~~		~~3,345~~		~~4,849~~		~~1,417~~		~~3,063~~		~~4,480~~
Total segment sales	9,~~997~~031		7,~~230~~109		1716,~~226~~140		8,~~714~~429		76,~~716~~797		1615,~~430~~226		~~27,252~~		~~20,897~~		~~48,148~~		~~23,980~~		~~23,858~~		~~47,838~~
Other (5)	15133		3413		50146		2293		~~206~~210		~~227~~303		~~119~~		~~343~~		~~463~~		~~109~~		~~597~~		~~706~~
	$	109,~~012~~164	$	7,~~264~~122	$	1716,~~276~~286	$	8,~~736~~522	$	7,~~922~~007	$	1615,~~657~~529	$	~~27,371~~	$	~~21,240~~	$	~~48,611~~	$	~~24,089~~	$	~~24,455~~	$	~~48,544~~

U.S. plus international may not equal total due to rounding.

(1) Alliance revenue for Lynparza and Lenvima represents Merck’s share of profits, which are product sales net of cost of sales and commercialization costs (see Note 3).

(2) Alliance revenue for Reblozyl represents royalties (see Note 3).

(3) Alliance revenue for Adempas/Verquvo represents Merck’s share of profits from sales in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs (see Note 3).

(4) Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately. Also reflects total alliance revenue for Koselugo of $~~214 million~~161 ~~and $39~~ million ~~in the third quarter of 2025~~ and ~~2024, respectively, and~~ $~~301~~44 million ~~and $114 million~~ in the first ~~nine~~quarter ~~months~~ of ~~2025~~2026 and ~~2024~~2025, respectively (see Note 3).

(5) Other is primarily comprised of miscellaneous corporate revenue, including revenue hedging activities which (decreased) increased sales by $(61110) million and $~~156~~58 million for the ~~nine~~three months ended ~~September~~March 3031, ~~2025~~2026 and ~~2024~~2025, respectively, as well as revenue from third-party manufacturing arrangements (including sales to Organon & Co.). Other for the ~~nine~~three months ended ~~September~~March 3031, ~~2025~~2026 and ~~2024~~2025 also includes $~~111~~132 million and $9195 million, respectively, related to ~~upfront and~~ milestone payments received by Merck for out-licensing arrangements.

- 3226 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Product sales are recorded net of the provision for discounts, including chargebacks, which are customer discounts that occur when a contracted customer purchases through an intermediary wholesale purchaser, and rebates that are owed based upon definitive contractual agreements or legal requirements with private sector and public sector (Medicaid and Medicare Part D) benefit providers, after the final dispensing of the product by a pharmacy to a benefit plan participant. These discounts, in the aggregate, reduced U.S. sales by $2.65 billion and $32.61 billion for the three months ended ~~September~~March 3031, ~~2025~~2026 and ~~2024, respectively, and $7.2 billion and $10.1 billion for the nine months ended September 30,~~ 2025 ~~and 2024~~, respectively.

Consolidated sales by geographic area where derived are as follows:

Three Months EndedSeptember 30,

Nine Months EndedSeptember 30,

Three Months EndedMarch 31,

($ in millions)

~~2025~~2026

~~2024~~2025

~~2025~~

~~2024~~

United States

109,~~012~~164

8,~~736~~522

~~27,371~~

~~24,089~~

Europe, Middle East and Africa

3,~~680~~886

3,~~583~~454

~~10,789~~

~~10,661~~

Latin America

~~905~~874

~~936~~792

~~2,556~~

~~2,591~~

Asia Pacific (other than China and Japan)

~~764~~738

~~823~~689

~~2,238~~

~~2,294~~

Japan

~~712~~555

~~938~~669

~~2,007~~

~~2,445~~

China

~~405~~390

~~1,017~~702

~~1,553~~

~~4,606~~

Other

~~798~~679

~~624~~701

~~2,097~~

~~1,858~~

1716,~~276~~286

1615,~~657~~529

~~48,611~~

~~48,544~~

A reconciliation of segment profits to (Loss) Income Before Taxes is as follows:

Three Months Ended September 30,

Nine Months Ended September 30,

Three Months Ended March 31,

2025

2024

2025

2024

2026

2025

($ in millions)

Pharma-ceutical

Animal Health

Total

Pharma-ceutical

Animal Health

Total

~~Pharma-ceutical~~

~~Animal Health~~

~~Total~~

~~Pharma-ceutical~~

~~Animal Health~~

~~Total~~

Segment sales

1514,~~611~~349

1,~~615~~791

1716,~~226~~140

1413,~~943~~638

1,~~487~~588

1615,~~430~~226

~~43,299~~

~~4,849~~

~~48,148~~

~~43,358~~

~~4,480~~

~~47,838~~

Less segment costs: (1)

Cost of sales

1,~~664~~553

~~710~~675

1,~~904~~573

~~613~~600

~~4,838~~

~~1,968~~

~~5,319~~

~~1,838~~

Selling, general and administrative

1,~~469~~332

~~277~~282

1,~~519~~402

~~268~~260

~~4,327~~

~~822~~

~~4,462~~

~~791~~

Research and development (2)

—

~~118~~112

—

~~323~~

—

~~276~~

Other segment items (3)

(6055)

~~(1)~~—

(2749)

(1)

~~(130)~~

~~(1)~~

~~(74)~~

Total segment profits

1211,~~538~~519

~~511~~722

1312,~~049~~241

1110,~~547~~712

~~510~~634

1211,~~057~~346

~~34,264~~

~~1,737~~

~~36,001~~

~~33,651~~

~~1,574~~

~~35,225~~

Other profits

4106

~~117~~202

~~235~~

~~391~~

Unallocated:

Interest income

9635

~~127~~109

~~274~~

~~269~~

Interest expense

(~~327~~479)

(~~330~~313)

~~(946)~~

~~(943)~~

Amortization

(~~623~~931)

(~~633~~597)

~~(1,820)~~

~~(1,720)~~

Depreciation

(~~449~~491)

(~~467~~441)

~~(1,345)~~

~~(1,368)~~

Research and development

(312,~~839~~404)

(53,~~716~~477)

~~(11,159)~~

~~(12,926)~~

Restructuring costs

(47195)

(5669)

~~(676)~~

~~(258)~~

Other unallocated, net

(1,~~119~~416)

(~~1,009~~857)

~~(2,917)~~

~~(2,904)~~

6(3,~~745~~534)

45,~~090~~903

~~17,647~~

~~15,766~~

(1) The significant expense categories and amounts align with the segment level information that is regularly provided to the chief operating decision maker.

(2) Human health-related research and development expenses incurred by Merck Research Laboratories are not allocated to segment profits as noted below.

(3) Includes equity (income) loss from affiliates and other miscellaneous non-operating expenses.

Pharmaceutical segment profits ~~are~~consist ~~comprised~~ of segment sales less standard costs, as well as selling, general and administrative expenses directly incurred by the segment. Animal Health segment profits ~~are~~consist ~~comprised~~ of segment sales, less all cost of sales, as well as selling, general and administrative expenses and research and development costs directly incurred by the segment. The chief operating decision maker (Merck’s Chief Executive Officer) uses segment profit tofor ~~allocate~~the purpose of evaluating performance, allocating resources, ~~predominately~~informing incentive compensation targets and setting strategic Company goals during the planning and forecasting process. On a quarterly basis, the CEO considers forecast-to-actual variances in segment profit when assessing performance of the segments and making decisions about allocating resources to the segments. For internal management reporting presented to the chief operating decision maker, Merck does not allocate the remaining cost of sales not included in segment profits as described above, research and development expenses incurred by Merck Research Laboratories, (the Company’s research and development division that focuses on human health-related activities), or general and administrative expenses not directly incurred by the segments, nor the cost of financing these activities. Separate divisions maintain responsibility for monitoring and managing these costs, including depreciation related to fixed assets utilized by these divisions and, therefore, they are not included in segment profits. In addition, costs related to restructuring activities, as well as the amortization of intangible assets and ~~amortization~~the recognition of ~~purchase~~fair ~~accounting~~value ~~adjustments~~step-up of inventories are not allocated to segments.

Other profits are primarily comprised of miscellaneous corporate profits, as well as operating profits (losses) related to third-party manufacturing arrangements.

- 3327 -

Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Other unallocated, net, includes expenses from corporate and manufacturing cost centers, intangible asset impairment charges, gains or losses on sales of businesses, expense or income related to changes in the estimated fair value measurement of liabilities for contingent consideration, and other miscellaneous income or expense items.

Equity income from affiliates and depreciation included in segment profits is as follows:

	Three Months Ended September 30,												Nine Months Ended September 30,
	Three Months Ended March 31,
	2025						2024						2025						2024
	2026						2025
($ in millions)	Pharma-ceutical		Animal Health		Total		Pharma-ceutical		Animal Health		Total		~~Pharma-ceutical~~		~~Animal Health~~		~~Total~~		~~Pharma-ceutical~~		~~Animal Health~~		~~Total~~
Equity income from affiliates	$	62	$	—	$	62	$	4358	$	—	$	4358	$	~~148~~	$	—	$	~~148~~	$	~~121~~	$	—	$	~~121~~
Depreciation	1		8289		8390		1		8560		8661		4		~~203~~		~~207~~		3		~~211~~		~~214~~

Property, plant and equipment, net, by geographic area where located is as follows:

($ in millions)	~~September~~March 3031, ~~2025~~2026		December 31, ~~2024~~2025
United States	$	15,~~482~~097	$	1415,~~724~~021
Europe, Middle East and Africa	8,~~665~~966		78,~~548~~856
Asia Pacific (other than China and Japan)	~~948~~842		~~982~~898
China	~~208~~213		~~202~~218
Japan	~~147~~136		~~143~~144
Latin America	~~139~~128		~~133~~128
Other	5051		4751
	$	25,~~639~~433	$	2325,~~779~~316

The Company does not disaggregate assets on a products and services basis for internal management reporting and, therefore, such information is not presented.

- 3428 -

Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Business Development Transactions

Below is a summary of significant business development activity thus far in ~~2025~~2026.

In ~~November~~March ~~2025~~2026, Merck ~~reached~~entered aninto a definitive agreement ~~with~~to ~~Dr.~~acquire ~~Falk~~Terns ~~Pharma~~Pharmaceuticals, ~~GmbH~~Inc. (~~Falk~~Terns), toa ~~discontinue~~clinical-stage anoncology ~~existing~~company, ~~contract~~for ~~concerning~~$53 ~~co-development~~per ~~and~~share, cofor a total transaction value of approximately $6.7 billion. Through this acquisition, Merck will acquire Terns’ lead candidate, TERN-~~commercialization~~701, ~~rights~~a novel investigational oral allosteric BCR::ABL1 tyrosine kinase inhibitor (TKI) currently being evaluated in ~~certain~~a ~~territories~~Phase 1/2 trial for ~~MK-8690~~patients ~~(formerly~~with ~~PRA~~Philadelphia chromosome-~~052)~~positive, ~~and~~chronic ~~for~~phase ~~Merck~~chronic tomyeloid ~~assume~~leukemia ~~full~~previously ~~responsibility~~treated ~~for~~with ~~the~~at ~~development~~least ~~program~~one ~~going~~prior ~~forward.~~TKI ~~MK-8690~~and iswho anexperienced ~~investigational~~treatment ~~anti-CD30~~failure, ~~ligand~~suboptimal ~~monoclonal~~response ~~antibody~~or ~~being~~treatment ~~evaluated~~intolerance. The transaction has been approved by ~~the~~both ~~Company~~Merck’s inand anTerns’ ~~early-stage~~Boards ~~clinical~~of ~~trial~~Directors. ~~Under~~The ~~the~~acquisition ~~terms~~is ofsubject ~~the~~to ~~agreement,~~a ~~Merck~~majority ~~and~~of ~~Falk~~Terns’ ~~have~~stockholders ~~discontinued~~tendering their ~~collaboration~~shares ~~based~~in onthe ~~their~~tender ~~existing~~offer ~~co-development~~initiated ~~contract~~by ~~resulting~~Merck in ~~Merck~~April ~~having~~2026. ~~secured~~The ~~global~~consummation ~~rights~~of the proposed transaction is also subject to ~~MK-8690~~customary closing conditions. InMerck ~~exchange,~~anticipates ~~Falk~~the transaction will ~~receive~~be aaccounted ~~$150~~for ~~million~~as ~~upfront~~an ~~payment,~~asset ~~which~~acquisition since TERN-701 is expected to account for substantially all of the ~~Company~~fair ~~will~~value ~~record~~of asthe agross ~~charge~~assets to ~~Research~~be acquired (excluding cash and ~~development~~deferred ~~expenses~~income intaxes). Upon closing of the ~~fourth~~transaction, ~~quarter~~which is anticipated in May 2026, Merck expects to record a charge of ~~2025~~approximately $5.8 billion to Research and development expenses, or approximately $02.0535 per share. ~~Falk~~There isare ~~also~~no ~~eligible~~future tocontingent ~~receive~~payments aassociated ~~developmental~~with ~~milestone~~the ~~payment~~acquisition. In addition, taking into consideration operational investment to advance TERN-701, as well as ~~tiered~~the ~~low-single-digit~~cost ~~royalties~~of onfinancing ~~sales~~the intransaction, ~~certain~~the ~~territories~~Company also anticipates a negative impact of approximately $0.12 per share over the remainder of 2026 following the closing of the transaction.

In ~~October~~January ~~2025~~2026, Merck acquired ~~Verona~~Cidara ~~Pharma~~Therapeutics, ~~plc~~Inc. (~~Verona Pharma~~Cidara), a ~~biopharmaceutical~~biotechnology company ~~focused~~developing ondrug-Fc ~~respiratory~~conjugate ~~diseases~~(DFC) therapeutics, for ~~total consideration of approximately~~ $109.52 billion (including $570 million of payments to settle share-based equity awards of which $406 million related to unvested equity awards). ~~Through~~Cidara’s ~~this~~lead ~~acquisition~~DFC candidate, ~~Merck~~MK-1406 ~~acquired Ohtuvayre~~ (~~ensifentrine~~formerly CD388), is a ~~first~~long-inacting antiviral designed to prevent seasonal and pandemic influenza. MK-~~class~~1406 ~~selective~~is ~~dual~~currently ~~inhibitor~~being ofevaluated ~~phosphodiesterases~~in a Phase 3 ~~and~~trial 4among ~~(PDE3~~adult and ~~PDE4),~~adolescent ~~which~~participants ~~was~~who ~~approved~~are inat ~~the~~higher Urisk of developing complications from influenza.S. inThe ~~June~~transaction ~~2024~~was accounted for as an asset acquisition since MK-1406 accounted for substantially all of the ~~maintenance~~fair ~~treatment~~value of ~~chronic~~the ~~obstructive~~gross ~~pulmonary~~assets ~~disease~~acquired (~~COPD~~excluding cash and deferred income taxes). inMerck ~~adult~~recorded ~~patients~~a charge of $9.0 billion to Research and isdevelopment ~~also~~expenses, ~~being~~or ~~evaluated~~$3.62 per share, (which primarily represented acquired in-process ~~clinical~~research ~~trials~~and ~~for~~development ~~the~~with ~~treatment~~no ofalternative ~~non-cystic~~future ~~fibrosis~~use), ~~bronchiectasis.~~as ~~The~~well ~~Company~~as isnet assets of $332 million in the ~~process~~first quarter of ~~determining~~2026. ~~the~~Under ~~fair~~a ~~value~~previous oflicense ~~assets~~agreement ~~acquired~~between Cidara and ~~liabilities~~J&J ~~assumed~~Innovative inMedicine ~~this~~(a ~~transaction;~~Johnson ~~however,~~& itJohnson ~~expects~~company, topreviously ~~capitalize~~Janssen ~~most~~Pharmaceuticals, ofInc.), ~~the~~which ~~purchase~~was ~~price~~assumed asby anMerck, ~~intangible~~J&J ~~asset~~Innovative ~~for~~Medicine ~~Ohtuvayre.~~is ~~There~~eligible ~~are~~to noreceive ~~future~~regulatory ~~contingent~~and ~~payments~~sales-based ~~associated~~milestones ~~with~~related ~~the~~to ~~acquisition~~MK-1406.

~~Also~~Pricing in October 2025, Merck and Blackstone Life Sciences (Blackstone) entered into a funding arrangement under which Blackstone will pay Merck $700 million (which is non-refundable, subject to the termination provisions of the agreement) to fund a portion of the Company’s development costs for MK-2870, sacituzumab tirumotecan (sac-TMT), expected to be incurred throughout 2026. The funding will be recognized as a reduction to Research and development expenses as Merck incurs applicable development costs for the sac-TMT program. Sac-TMT is an investigational trophoblast cell-surface antigen 2 (TROP2)-directed ADC being developed as part of an exclusive license and collaboration agreement with Kelun-Biotech that is currently in clinical development for the treatment of a variety of cancers. The agreement between Merck and Kelun-Biotech with respect to sac-TMT is unchanged by the new agreement with Blackstone. Merck will retain decision-making authority and control over the development, manufacturing, and commercial activities relating to sac-TMT provided for in the agreement with Kelun-Biotech, and Blackstone will not receive any rights to sac-TMT. Upon receipt of regulatory approval for an indication in the U.S. for first-line triple-negative-breast cancer (TroFuse-011 trial), Blackstone will be eligible to receive low-to-mid single-digit royalties on net sales of sac-TMT subsequent to such approval across all approved indications in Merck’s marketing territories.

InGlobal ~~July~~efforts ~~2025,~~toward ~~the~~health ~~technology~~care ~~transfer~~cost ~~for~~containment ~~MK-2010~~continue ~~(LM-299),~~to aexert ~~novel~~pressure ~~investigational~~on ~~PD-1/vascular~~product ~~endothelial~~pricing ~~growth~~and ~~factor~~market ~~(VEGF)~~access ~~bispecific~~worldwide. ~~antibody~~Changes ~~that~~to ~~was~~the ~~licensed~~U.S. ~~from~~health ~~LaNova~~care ~~Medicines~~system ~~Ltd~~as ~~(LaNova)~~part inof ~~2024,~~health ~~was~~care ~~completed. Accordingly~~reform, ~~Merck~~as ~~made~~well aas ~~$300 million~~increased ~~payment~~purchasing topower ~~LaNova~~of ~~(which~~entities ~~has been acquired by Sino Biopharmaceutical Limited)~~ that ~~was~~negotiate ~~recorded~~on asbehalf aof ~~charge~~Medicare, toMedicaid, ~~Research~~ and ~~development~~private ~~expenses~~sector ~~in the third quarter and first nine months of 2025~~beneficiaries, orhave ~~approximately~~contributed ~~$0.10~~to ~~per~~pricing ~~share~~pressure.

In ~~May 2025~~2021, ~~Merck~~the ~~and Jiangsu Hengrui Pharmaceuticals Co~~U.~~, Ltd~~S. ~~(Hengrui~~Congress ~~Pharma)~~passed ~~closed~~the anAmerican ~~exclusive~~Rescue ~~license~~Plan ~~agreement for MK-7262 (HRS-5346)~~Act, ~~an investigational oral small molecule Lipoprotein(a) inhibitor,~~ which isincluded ~~currently being evaluated in~~ a ~~Phase~~provision 2that ~~clinical~~eliminated ~~trial in China. Under~~ the ~~agreement,~~statutory ~~Hengrui~~cap ~~Pharma~~on ~~granted~~rebates ~~Merck~~drug ~~exclusive~~manufacturers ~~rights~~pay to ~~develop,~~Medicaid ~~manufacture~~beginning ~~and commercialize MK-7262 (HRS-5346) worldwide, excluding the Greater China region. Merck recorded a charge of $200 million to Research and development expenses~~ in ~~the~~January ~~first nine months of 2025, or approximately $0~~2024.06 per share, for the upfront payment. Hengrui Pharma is also eligible to receive future contingent payments associated with certain developmental, regulatory and sales-based milestones, as well as tiered royalties on future net sales of MK-7262 (HRS-5346), if approved.

In ~~March~~2022, ~~2025~~the U.S. Congress passed the Inflation Reduction Act (IRA), ~~Merck~~which ~~acquired~~made significant changes to how drugs are covered and paid for under the ~~Dundalk~~Medicare program, ~~Ireland~~including ~~facility~~the creation of ~~WuXi~~financial ~~Vaccines~~penalties for drugs whose prices rise faster than the rate of inflation, redesign of the Medicare Part D program to require manufacturers to bear more of the liability for certain drug benefits (awhich ~~wholly~~went ~~owned~~into ~~subsidiary~~effect in 2025), and government price-setting for certain Medicare Part D drugs (starting in 2026) and Medicare Part B drugs (starting in 2028). The U.S. Department of ~~WuXi~~Health ~~Biologics~~and Human Services (HHS), ~~which~~through ~~was~~the ~~accounted~~Centers for asMedicare an& ~~asset~~Medicaid ~~acquisition~~Services (CMS), selected Januvia (sitagliptin) in 2023 for the first year of the IRA’s “Drug Price Negotiation Program” (Program), and selected Janumet (sitagliptin and metformin HCl) and Janumet XR (sitagliptin and metformin HCl extended release) in 2025 for the second year of the IRA’s Program. ~~Merck~~Pursuant ~~paid~~to ~~$437~~the ~~million~~IRA’s atProgram, ~~closing~~the ~~which~~government set a price for Januvia, ~~combined~~which ~~with~~became ~~previous~~effective ~~consideration~~on ~~transferred~~January ~~under~~1, 2026, and set a ~~prior~~price ~~manufacturing~~for ~~arrangement~~Janumet ~~with~~and ~~WuXi~~Janumet ~~Vaccines~~XR, ~~related~~which towill ~~this~~become ~~facility~~effective on January 1, ~~resulted~~2027. In addition, in ~~$759 million~~January ~~being~~2026, ~~recorded~~HHS asannounced ~~assets~~that ~~under~~Lenvima ~~construction~~(lenvatinib) ~~within~~has ~~Property~~been selected for government price setting, ~~Plant~~the ~~and~~set ~~Equipment~~price for which will become effective on January 1, 2028. ~~There~~Furthermore, ~~are~~the noCompany ~~future~~expects ~~contingent~~that ~~payments~~Keytruda ~~associated~~(pembrolizumab) ~~with~~will be selected in 2027 for government price setting, which would become effective on January 1, 2029. Government price setting may also impact pricing in the ~~acquisition~~private market negatively affecting the Company’s performance. The Company has sued the U.S. government regarding the IRA’s Program.

~~Pricing~~Additionally, increased utilization of the 340B Federal Drug Discount Program and ~~Tariffs~~restrictions on the Company’s ability to identify inappropriate discounts are having a negative impact on Company performance. Furthermore, the Executive Branch and Congress continue to discuss legislation designed to control health care costs, including the cost of drugs. In several international markets, government-mandated pricing actions have reduced prices of generic and patented drugs. In addition, the Company’s sales performance in the first three months of 2026 was negatively affected by other cost-reduction measures taken by governments and other third parties to lower health care costs.

Global efforts toward health care cost containment continue to exert pressure on product pricing and market access worldwide. Changes to the U.S. health care system as part of health care reform, as well as increased purchasing power of entities that negotiate on behalf of Medicare, Medicaid, and private sector beneficiaries, have contributed to pricing pressure. In 2021, the U.S. Congress passed the American Rescue Plan Act, which included a provision that eliminated the statutory cap on rebates drug manufacturers pay to Medicaid beginning in January 2024. As a result of this provision, the Company paid state Medicaid programs more in rebates than it received on Medicaid sales of Januvia (sitagliptin), Janumet (sitagliptin and metformin HCl) and Janumet XR (sitagliptin and metformin HCl extended release) in 2024.

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In 2022, the U.S. Congress passed the Inflation Reduction Act (IRA), which made significant changes to how drugs are covered and paid for under the Medicare program, including the creation of financial penalties for drugs whose prices rise faster than the rate of inflation, redesign of the Medicare Part D program to require manufacturers to bear more of the liability for certain drug benefits (which has taken effect in 2025), and government price-setting for certain Medicare Part D drugs (starting in 2026) and Medicare Part B drugs (starting in 2028). Government price setting may also impact pricing in the private market negatively affecting the Company’s performance. In 2023, the U.S. Department of Health and Human Services (HHS), through the Centers for Medicare & Medicaid Services (CMS), selected Januvia for the first year of the IRA’s “Drug Price Negotiation Program” (Program). Pursuant to the IRA’s Program, a government price was set for Januvia, which will become effective on January 1, 2026. In January 2025, the U.S. Department of HHS, through the CMS, announced that Janumet and Janumet XR would be in included in the second year of the IRA’s Program, with government price setting to become effective on January 1, 2027. As a result of the passage of H.R.1 - One Big Beautiful Bill Act (OBBBA), the Company believes that Keytruda will not be eligible to be selected in 2026 for government price setting under the IRA, which would become effective on January 1, 2028. Instead, Keytruda will now be eligible to be selected in 2027 for government price setting to become effective on January 1, 2029. The Company has sued the U.S. government regarding the IRA’s Program.

Additionally, increased utilization of the 340B Federal Drug Discount Program and restrictions on the Company’s ability to identify inappropriate discounts are having a negative impact on Company performance. Furthermore, the Executive Branch and Congress continue to discuss legislation designed to control health care costs, including the cost of drugs. In several international markets, government-mandated pricing actions have reduced prices of generic and patented drugs. In addition, the Company’s sales performance in the first nine months of 2025 was negatively affected by other cost-reduction measures taken by governments and other third parties to lower health care costs.

The Company anticipates all of these actions and additional actions in the future will continue to negatively affect sales and profits.

~~The~~In ~~U.S.~~May ~~government~~2025, ~~has implemented tariffs on certain foreign imports into~~ the U.S. ~~The~~presidential ~~impact~~administration ofissued ~~the~~an ~~tariffs~~executive onorder ~~Merck’s~~intended ~~business~~to ~~depends~~encourage ~~on a number of factors including the duration, scope and amount of the tariffs, as well as the extent of any measures that have been~~ or ~~will~~impose ~~be taken by any affected countries, including tariffs imposed by foreign governments. At this time,~~ the ~~Company~~use ~~anticipates that tariffs implemented to date will result in less than $100 million~~ of ~~additional~~“most-favored-nation” ~~expenses~~pricing ~~in 2025 (which will be primarily reflected within Cost of sales). However, future changes~~ to ~~tariffs~~tie ~~could have a further adverse effect on the Company’s business. In particular, the~~ U.S. ~~government~~prescription ~~has~~drug ~~indicated~~prices ~~that~~to itprices ~~may~~in ~~impose~~selected ~~tariffs~~comparably ondeveloped ~~pharmaceutical products~~nations. In July

In- ~~addition,~~29 in May 2025, the U.S. government announced an executive order that seeks to impose a “Most Favored Nation” drug pricing policy. The policy would tie drug reimbursement in the U.S. to the drug price in certain foreign developed countries and could result in reduced prices and reimbursement for certain of the Company’s products in the U.S. The impact of this executive order to the Company is uncertain and will be dependent upon many factors, including if and how this drug pricing policy is implemented.-

2025, the Company and other pharmaceutical companies received letters from the U.S. presidential administration with a request to agree to the administration’s “most-favored-nation” drug pricing goals by September 29, 2025. Further to the letter received from the administration, in December 2025, the Company announced that it had entered into a three-year agreement (MFN Agreement) with the U.S government that addressed the four policy goals of the administration’s July letter. Included within the MFN Agreement is an obligation by the Company to provide key products through a direct-to-patient program at affordable prices for eligible patients in the U.S. This will initially include Januvia, Janumet and Janumet XR, and will be expanded in the future to include enlicitide decanoate pending FDA approval. The Company also agreed to offer its existing medicines at discounted prices to Medicaid, excluding certain products. Additionally, the Company agreed that products launched during the term of the MFN Agreement (with certain exceptions) will be subject to “most-favored-nation” pricing in reference to prices for such products in a specified group of countries (MFN Countries). Finally, the Company agreed to repatriate and share with the Federal government a portion of foreign revenue received by the Company as a result of the government’s successful trade policy efforts. Additionally, the Company reached an agreement with the U.S. Department of Commerce to delay Section 232 tariffs for three years, enabling the Company to make investments in the U.S. to reshore manufacturing for American patients.

Operating Results

Sales

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
	Three Months EndedMarch 31,						% Change Excluding ForeignExchange
($ in millions)	~~2025~~2026		~~2024~~2025		% Change				~~2025~~		~~2024~~		~~% Change~~
United States	$	109,~~012~~164	$	8,~~736~~522	158	%	158	%	$	~~27,371~~	$	~~24,089~~	14	%	14	%
International	7,~~264~~122		7,~~922~~007		~~(8)~~2	%	(93)	%	~~21,240~~		~~24,455~~		~~(13)~~	%	~~(12)~~	%
Total	$	1716,~~276~~286	$	1615,~~657~~529	45	%	3	%	$	~~48,611~~	$	~~48,544~~	—	%	1	%

UWorldwide sales were $16.S.3 ~~plus~~billion ~~international~~in ~~may~~the ~~not~~first ~~equal~~quarter ~~total~~of ~~due~~2026, toan ~~rounding~~increase of 5% compared with the first quarter of 2025, reflecting growth in oncology, cardiometabolic and respiratory, and animal health, partially offset by declines in vaccines, diabetes, and infectious diseases.

~~Worldwide~~Growth ~~sales~~in ~~were~~the ~~$17.3~~oncology ~~billion~~franchise in the ~~third~~first quarter of ~~2025,~~2026 anwas ~~increase~~largely due to the performance of 4%Keytruda ~~compared~~and ~~with~~Welireg ~~the~~(belzutifan), ~~third~~as ~~quarter~~well ofas ~~2024.~~higher ~~Global~~alliance ~~sales~~revenue ~~were~~from ~~$48~~Koselugo (selumetinib) resulting from an amendment to the collaboration agreement.6 ~~billion~~Sales growth in the ~~first~~cardiometabolic ~~nine~~and ~~months~~respiratory franchise was largely attributable to the continued uptake of ~~2025~~Winrevair (sotatercept-csrk), upas ~~slightly~~well ~~compared~~as ~~with~~the inclusion of sales of Ohtuvayre (ensifentrine) (which was obtained as part of the ~~same~~October ~~period~~2025 acquisition of ~~2024~~Verona Pharma plc [Verona Pharma]). ~~The~~Animal health sales ~~increase~~growth inwas due to the performance of both ~~periods~~livestock ~~reflects~~and ~~growth~~companion inanimal ~~oncology,~~products. ~~cardiovascular~~The vaccines revenue decline was primarily due to lower combined Gardasil (Human Papillomavirus Quadrivalent [Types 6, ~~diabetes~~11, 16 and ~~animal~~18] ~~health~~Vaccine Recombinant) and Gardasil 9 (Human Papillomavirus 9-valent Vaccine, ~~partially~~Recombinant) ~~offset~~sales. byThe ~~declines~~decline in ~~vaccines,~~diabetes ~~immunology~~was primarily due to lower sales of Januvia, and ~~virology.~~the decline in infectious diseases was largely due to lower sales of Lagevrio (molnupiravir).

~~Growth~~See inNote 15 ~~the~~to ~~oncology franchise in both~~ the ~~third~~condensed ~~quarter~~consolidated ~~and~~financial ~~first~~statements ~~nine~~for ~~months~~details ofon ~~2025~~sales ~~was largely due to the performance~~ of ~~Keytruda (pembrolizumab) and Welireg (belzutifan), as well as higher alliance revenue from Koselugo (selumetinib), resulting from an amendment to~~ the ~~collaboration~~Company’s ~~agreement, and Lynparza (olaparib)~~products. ~~The~~A ~~sales~~discussion ~~increase in the cardiovascular franchise in both periods was largely attributable to the ongoing launch~~ of ~~Winrevair~~performance ~~(sotatercept-csrk)~~for ~~and~~select ~~growth~~products in the ~~diabetes~~franchises ~~franchise~~follows. ~~was~~All ~~largely~~product ~~due~~or toservice ~~Januvia.~~marks ~~Animal~~appearing ~~health sales growth~~ in ~~both~~type ~~periods~~form ~~was~~different ~~largely~~from ~~due~~that ~~to the performance~~ of ~~livestock products. The vaccines revenue decline in both~~ the ~~third~~surrounding ~~quarter~~text ~~and~~are ~~first~~trademarks ~~nine~~or ~~months~~service ofmarks ~~2025~~owned, ~~was~~licensed ~~primarily due~~ to, ~~lower~~or ~~combined~~distributed ~~Gardasil~~by ~~(Human Papillomavirus Quadrivalent [Types 6~~Merck, ~~11,~~its 16subsidiaries ~~and~~or ~~18] Vaccine Recombinant) and Gardasil 9 (Human Papillomavirus 9-valent Vaccine~~affiliates, ~~Recombinant)~~except ~~sales,~~as ~~partially offset by the ongoing U~~noted.S. ~~launch~~All ofother ~~Capvaxive~~trademarks ~~(Pneumococcal~~or ~~21-valent~~service ~~Conjugate~~marks ~~Vaccine)~~are ~~and~~those ~~initial stocking~~ of ~~Enflonsia~~their ~~(clesrovimab-cfor)~~respective ~~related to the U~~owners.S. launch. The declines in immunology in both periods resulted from the transfer of marketing rights for Simponi (golimumab) and Remicade (infliximab) back to Johnson & Johnson on October 1, 2024, and the declines in virology were largely due to lower sales of Lagevrio (molnupiravir).

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See Note 15 to the condensed consolidated financial statements for details on sales of the Company’s products. A discussion of performance for select products in the franchises follows. All product or service marks appearing in type form different from that of the surrounding text are trademarks or service marks owned, licensed to, promoted or distributed by Merck, its subsidiaries or affiliates, except as noted. All other trademarks or service marks are those of their respective owners.

Pharmaceutical Segment

Oncology

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
	Three Months EndedMarch 31,						% Change Excluding ForeignExchange
($ in millions)	~~2025~~2026		~~2024~~2025		% Change				~~2025~~		~~2024~~		~~% Change~~
Keytruda	$	8,142	$	7,429	10	%	8	%	$	23,303	$	21,646	8	%	8	%
Keytruda/Keytruda Qlex	$	8,034	$	7,205	12	%	8	%
Alliance Revenue - Lynparza (1)	~~379~~341		~~337~~312		129	%	126	%	~~1,061~~		~~947~~		12	%	12	%
Alliance Revenue - Lenvima (1)	258		251		3	%	2	%	781		755		3	%	3	%
Welireg	199		137		45	%	43	%
Welireg	196		139		42	%	41	%	496		349		42	%	42	%
Alliance Revenue - Koselugo (2)	161		44		*		*
Alliance Revenue - Reblozyl (2)	136		100		36	%	36	%	361		261		39	%	39	%
Alliance Revenue - Reblozyl (3)	148		119		25	%	25	%
Alliance Revenue - Koselugo (3)	214		39		*		*		301		114		*		*

* > 100%

(1) Alliance revenue for Lynparza ~~and Lenvima~~ represents Merck’s share of profits, which are product sales net of cost of sales and commercialization costs (see Note 3 to the condensed consolidated financial statements).

(2) Alliance revenue for ~~Reblozyl~~Koselugo in 2026 primarily includes a $150 million payment received in connection with an amendment to the collaboration agreement with AstraZeneca in August 2025, which revised the payment structure. Alliance revenue in the first quarter of 2025 represents ~~royalties~~Merck’s share of profits, which are product sales net of cost of sales and commercialization costs. (~~see~~See Note 3 to the condensed consolidated financial statements) for more information on this collaboration, including the above referenced amendment.)

(3) Alliance revenue for ~~Koselugo~~Reblozyl in both periods of 2025 primarily includes a $150 million upfront payment and a $50 million regulatory milestone recorded in connection with an amendment to the collaboration agreement, which revised the payment structure. Alliance revenue in both periods of 2024 represents ~~Merck’s~~royalties ~~share of profits, which are product sales net of cost of sales and commercialization costs.~~ (~~See~~see Note 3 to the condensed consolidated financial statements ~~for more information on this collaboration, including the above referenced amendment.~~).

Keytruda is an anti-PD-1 (programmed death receptor-1) therapy that has been approved in over 40 indications in the U.S., including 1819 tumor types and 2 tumor-agnostic indications, and has similarly been approved in markets worldwide for many of these indications. ~~The~~ Keytruda ~~clinical~~Qlex ~~development~~is ~~program~~a ~~includes~~subcutaneously-administered ~~studies~~fixed ~~across~~combination aof ~~broad~~pembrolizumab ~~range~~and ofberahyaluronidase ~~cancer~~alfa, ~~types.~~which ~~See~~enhances ~~“Research~~dispersion and ~~Development~~permeability ~~Update”~~to ~~below~~enable subcutaneous administration of pembrolizumab.

Global sales of Keytruda grew 10% and 8% in the third quarter and first nine months of 2025, respectively. Keytruda sales growth in the U.S. in both periods reflects higher demand and net pricing. Demand in the U.S. in both periods was driven by increased utilization across the multiple approved metastatic indications, in particular for the treatment of certain types of urothelial, endometrial, and head and neck cancers, as well as higher demand across earlier-~~stage~~ ~~indications,~~30 ~~including in certain types of non~~-small cell lung cancer (NSCLC), cervical cancer, triple-negative breast cancer (TNBC), and renal cell carcinoma (RCC). U.S. Keytruda sales in the third quarter of 2025 reflect a benefit of approximately $100 million due to the timing of wholesaler purchases, partially offset by other channel movements. Keytruda sales growth in international markets reflects higher demand predominately for the TNBC, NSCLC, and RCC earlier-stage indications, as well as uptake in urothelial, gastric, cervical, and endometrial cancer metastatic indications. The 2025 launch and reimbursement of new indications for Keytruda in the European Union (EU) is having a negative impact on pricing in those markets. In addition, a biosimilar of Keytruda has launched in Argentina.

Keytruda ~~has~~Qlex, ~~received~~which was initially approved by the ~~following~~FDA ~~regulatory~~in ~~approvals~~September ~~thus~~2025, ~~far~~is approved in the U.S. in solid tumor indications approved for Keytruda. In November 2025, the European Commission (EC) approved a new subcutaneous (SC) route of administration and a new pharmaceutical form (solution for injection) of Keytruda (to be marketed as Keytruda SC) for use across Keytruda indications for adults in Europe. Timing for commercial availability of Keytruda SC in individual European Union (EU) countries for approved indications will vary by country and depend on multiple factors, including the completion of reimbursement procedures and the outcome of litigation with Halozyme, Inc. as discussed in Note 8 to the condensed consolidated financial statements. The Keytruda and Keytruda Qlex clinical development programs include studies across a broad range of cancer types. See “Research and Development Update” below.

Date			Approval
January 2025			China’s National Medical Products Administration (NMPA) approval in combination with enfortumab vedotin, an antibody-drug conjugate, for the treatment of adults with locally advanced or metastatic urothelial carcinoma, based on the KEYNOTE-A39 trial that was conducted in collaboration with Seagen (now Pfizer Inc.) and Astellas.
April 2025			European Commission (EC) approval in combination with pemetrexed and platinum chemotherapy for the first-line treatment of adult patients with unresectable non epithelioid malignant pleural mesothelioma, based on the IND.227/KEYNOTE-483 trial.
May 2025			Japan’s Ministry of Health, Labor and Welfare (MHLW) approval in combination with trastuzumab and chemotherapy for the first-line treatment of patients with unresectable, advanced or recurrent human epidermal growth factor receptor 2 (HER2) positive gastric or gastroesophageal junction adenocarcinoma, based on the KEYNOTE-811 trial.
May 2025			Japan’s MHLW approval in combination with pemetrexed and platinum chemotherapy for unresectable, advanced or recurrent metastatic malignant pleural mesothelioma, based on the IND.227/KEYNOTE-483 trial.
June 2025			U.S. Food and Drug Administration (FDA) approval for the treatment of adult patients with resectable locally advanced head and neck squamous cell carcinoma (HNSCC) whose tumors express PD-L1 Combined Positive Score (CPS) ≥1 as determined by an FDA-approved test, as a single agent as neoadjuvant treatment, continued as adjuvant treatment in combination with radiotherapy with or without cisplatin and then as a single agent, based on the KEYNOTE-689 trial.
October 2025			EC approval as monotherapy for the treatment of resectable locally advanced HNSCC as neoadjuvant treatment, continued as adjuvant treatment in combination with radiation therapy with or without concomitant cisplatin and then as monotherapy in adults whose tumors express PD-L1 with a CPS ≥1, based on the KEYNOTE-689 trial.

Combined global sales of Keytruda/Keytruda Qlex grew 12% in the first quarter of 2026. Sales growth in the U.S. reflects an approximate $250 million favorable impact due to the timing of wholesaler purchases, higher net pricing, and increased demand. Demand in the U.S. was driven by higher utilization across earlier-stage indications, including in certain types of cervical cancer, triple-negative breast cancer (TNBC), and renal cell carcinoma (RCC), as well as higher demand across multiple metastatic indications, in particular for the treatment of certain types of urothelial and cervical cancers. Sales growth in international markets reflects higher demand in urothelial, non-small cell lung cancer (NSCLC), gastric, cervical, and endometrial cancer metastatic indications, as well as increased uptake predominately for the TNBC, NSCLC, melanoma, and RCC earlier-stage indications. The launch and reimbursement of new indications for Keytruda in the EU continues to have a negative impact on pricing in those markets. In addition, a biosimilar of Keytruda launched in Argentina in 2025 and the Company expects further launches in smaller international markets during 2026. The Company anticipates the impact of biosimilar erosion to Keytruda sales will be immaterial in 2026.

-Keytruda 37has -received the following regulatory approvals thus far in 2026.

The Company is a party to license agreements pursuant to which the Company pays royalties on net sales of Keytruda. Under the terms of the more significant of these agreements, Merck pays a royalty of 2.5% on worldwide net sales of Keytruda; this royalty expires on December 31, 2026. The Company pays an additional 2% royalty on worldwide net sales of Keytruda to another third party, the termination date of which varies by country; this royalty expired in the U.S. in September 2024 and expired in several major European markets in the third quarter of 2025, with the royalty set to expire in the remaining major European markets in the fourth quarter of 2025. The royalty expenses are included in Cost of sales.


Date			Approval
February 2026			China’s National Medical Products Administration (NMPA) approval for the first-line treatment of certain patients with primary advanced or recurrent endometrial cancer, based on the KEYNOTE-868 (NRG-GY018) trial.
February 2026			U.S. Food and Drug Administration (FDA) approval in combination with paclitaxel, with or without bevacizumab, for the treatment of adult patients with platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal carcinoma whose tumors express programmed death-ligand (PD-L1) Combined Positive Score (CPS) ≥ 1 as determined by an FDA-authorized test, and who have received one or two prior systemic treatment regimens, based on the KEYNOTE-B96 trial.
February 2026			Japan’s Ministry of Health, Labor and Welfare (MHLW) approval for neoadjuvant and adjuvant treatment of locally advanced head and neck squamous cell carcinoma, based on the KEYNOTE-689 trial.
March 2026			EC approval in combination with paclitaxel, with or without bevacizumab, for the treatment of platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal carcinoma in adults whose tumors express PD-L1 (CPS ≥1) and who have received one or two prior systemic treatment regimens, based on the KEYNOTE-B96 trial.

~~In September 2025, the FDA approved~~ Keytruda Qlex (~~pembrolizumab~~available ~~and~~in ~~berahyaluronidase~~some ~~alfa-pmph)~~markets ~~injection~~as ~~for subcutaneous administration across most solid tumor indications for~~ Keytruda, ~~and~~SC) ~~subsequently~~received ~~approved Keytruda Qlex for~~ the ~~treatment~~following ofregulatory ~~certain~~approvals ~~adult~~thus ~~patients~~far ~~with~~in ~~resectable locally advanced HNSCC so that Keytruda Qlex is now approved across all solid tumor indications for Keytruda~~2026.

Lynparza is an oral poly (ADP-ribose) polymerase (PARP) inhibitor being developed and commercialized as part of a collaboration with AstraZeneca PLC (AstraZeneca) (see Note 3 to the condensed consolidated financial statements). Lynparza is approved for the treatment of certain types of advanced or recurrent ovarian, early or metastatic breast, metastatic pancreatic and metastatic castration-resistant prostate cancers. Alliance revenue related to Lynparza increased 12% in both the third quarter and first nine months of 2025, primarily due to higher demand in the U.S. and certain international markets. In January 2025, China’s NMPA approved Lynparza as adjuvant treatment for adult patients with germline BRCA-mutated, HER2-negative high-risk early breast cancer, based on the OlympiA trial.


Date			Approval
February 2026			FDA approval in combination with paclitaxel, with or without bevacizumab, for the treatment of adult patients with platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal carcinoma whose tumors express PD-L1 (CPS ≥ 1) as determined by an FDA-authorized test, and who have received one or two prior systemic treatment regimens, based on the KEYNOTE-B96 trial.
March 2026			EC approval in combination with paclitaxel, with or without bevacizumab, for the treatment of platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal carcinoma in adults whose tumors express PD-L1 (CPS ≥1) and who have received one or two prior systemic treatment regimens, based on the KEYNOTE-B96 trial.
April 2026			FDA approval of a label update based on results from the MK-3475A-F11 trial, which evaluated patient reported preference for subcutaneous administration of Keytruda Qlex over intravenous administration of Keytruda in participants with multiple tumor types.

~~Lenvima~~The ~~(lenvatinib)~~Company is ana ~~oral~~party ~~receptor~~to ~~tyrosine~~license ~~kinase~~agreements ~~inhibitor~~pursuant ~~being~~to ~~developed~~which ~~and~~the ~~commercialized~~Company aspays ~~part~~royalties on net sales of aKeytruda. ~~collaboration~~Under ~~with~~the ~~Eisai~~terms ~~Co.,~~of ~~Ltd.~~the ~~(Eisai)~~more ~~(see~~significant ~~Note 3~~of tothese ~~the~~agreements, ~~condensed~~Merck ~~consolidated~~pays ~~financial~~a ~~statements).~~royalty ~~Lenvima~~of is2.5% ~~approved~~on ~~for~~worldwide ~~the~~net ~~treatment~~sales of ~~certain~~Keytruda; ~~types~~this ofroyalty ~~thyroid~~(which ~~cancer,~~also ~~RCC,~~applies ~~hepatocellular~~to ~~carcinoma~~net ~~(HCC~~sales of Keytruda Qlex) will continue through 2026, interminating ~~combination~~thereafter. ~~with~~The ~~everolimus~~Company ~~for~~pays ~~certain~~an ~~patients~~additional ~~with~~2% ~~advanced~~royalty ~~RCC,~~on ~~and~~worldwide innet ~~combination~~sales ~~with~~of Keytruda ~~for~~(and ~~certain~~on ~~patients~~Keytruda ~~with~~Qlex ~~advanced~~following ~~endometrial~~regulatory ~~carcinoma~~approval) orto ~~advanced~~another ~~RCC.~~third ~~Alliance~~party; ~~revenue~~this ~~related~~royalty toexpired ~~Lenvima~~in ~~increased~~the 3%U.S. in ~~both~~2024, ~~the~~expired ~~third~~in ~~quarter~~major ~~and~~European ~~first~~markets ~~nine~~in ~~months~~the second half of 2025, ~~primarily~~but ~~due~~will continue to ~~higher~~be ~~sales~~paid inon ~~the~~net ~~U.S.~~sales ~~reflecting~~of ~~increased~~Keytruda ~~demand~~and ~~that~~Keytruda ~~was~~Qlex ~~partially~~in ~~offset~~certain byother ~~lower~~international ~~net~~markets ~~pricing.~~expiring Inat ~~June~~various ~~2025,~~dates ~~Lenvima~~through ~~plus~~2035. ~~Keytruda~~The ~~was~~royalty ~~approved~~expenses inare ~~China~~included in ~~combination~~Cost ~~with~~of ~~transarterial~~sales. ~~chemoembolization~~The ~~for~~Company ~~the~~may ~~treatment~~be ofsubject ~~patients~~to ~~with~~additional ~~unresectable,~~royalties ~~non-metastatic~~on ~~HCC~~net ~~based~~sales onof Keytruda Qlex in the ~~LEAP-012~~future ~~clinical~~under ~~trial~~certain circumstances.

~~Sales~~Lynparza of(olaparib) ~~Welireg,~~is ~~for~~an ~~the~~oral ~~treatment~~poly of(ADP-ribose) ~~adult~~polymerase ~~patients~~(PARP) ~~with~~inhibitor ~~certain~~being ~~von~~developed ~~Hippel-Lindau~~and ~~(VHL)~~commercialized ~~disease-associated~~as ~~tumors,~~part ~~certain~~of ~~adult~~a ~~patients~~collaboration with ~~previously~~AstraZeneca ~~treated~~PLC ~~advanced~~(AstraZeneca) ~~RCC,~~(see ~~and~~Note 3 ~~certain~~to ~~patients~~the ~~with~~condensed ~~pheochromocytoma~~consolidated ~~and~~financial ~~paraganglioma,~~statements). ~~rose~~Lynparza ~~42%~~is inapproved ~~both~~for the ~~third~~treatment ~~quarter~~of ~~and~~certain ~~first~~types ~~nine months~~ of ~~2025~~advanced ~~primarily~~or ~~due~~recurrent toovarian, ~~higher~~early ~~demand~~or inmetastatic ~~the~~breast, ~~U.S.~~metastatic pancreatic and ~~continued~~metastatic ~~launch~~castration-resistant ~~uptake~~prostate incancers. ~~certain~~Alliance ~~international~~revenue ~~markets,~~related ~~particularly~~to Lynparza grew 9% in the ~~EU,~~first ~~partially~~quarter ~~offset~~of by2026 ~~lower~~largely ~~net~~due ~~pricing~~to higher demand in the U.S. and many international markets.

~~Welireg~~- ~~has~~31 ~~received the following regulatory approvals thus far in 2025.~~-

Date			Approval
February 2025			EC conditional approval as monotherapy for the treatment of adult patients with VHL disease who require therapy for associated, localized RCC, central nervous system hemangioblastomas, or pancreatic neuroendocrine tumors, and for whom localized procedures are unsuitable, based on the LITESPARK-004 trial.
February 2025			EC conditional approval for the treatment of adult patients with advanced clear cell RCC that progressed following two or more lines of therapy that included a PD-1 or PD-L1 inhibitor and at least two vascular endothelial growth factor targeted therapies, based on the LITESPARK-005 trial.
May 2025			FDA approval for the treatment of adult and pediatric patients (12 years and older) with locally advanced, unresectable, or metastatic pheochromocytoma and paraganglioma, based on the LITESPARK-015 trial.
June 2025			Japan’s MHLW approval as monotherapy for the treatment of adult patients with VHL disease-associated tumors, based on the LITESPARK-004 trial.
June 2025			Japan’s MHLW approval for the treatment of adults with radically unresectable or metastatic RCC that has progressed after chemotherapy, based on the LITESPARK-005 trial.

Sales of Welireg, for the treatment of adult patients with certain von Hippel-Lindau (VHL) disease-associated tumors, certain adult patients with previously treated advanced RCC, and certain patients with pheochromocytoma and paraganglioma, rose 45% in the first quarter of 2026 primarily due to higher demand in the U.S. for the RCC indication and continued launch uptake in several international markets, particularly in Japan and certain European markets.

~~The~~Koselugo ECis ~~conditional~~an ~~approvals~~oral, selective MEK inhibitor approved for the treatment of ~~Welireg~~patients ~~noted~~with ~~above~~neurofibromatosis ~~will~~type be1 ~~valid~~who ~~for~~have ~~one~~symptomatic ~~year,~~inoperable ~~subject~~plexiform toneurofibromas. ~~yearly~~Koselugo ~~renewal,~~is ~~pending~~part ~~certain~~of ~~additional~~a ~~clinical~~collaboration ~~data~~with AstraZeneca. ~~Timing~~The ~~for~~increase ~~commercial~~in ~~availability~~alliance revenue in the first quarter of ~~Welireg~~2026 is due to a $150 million payment received in ~~individual~~connection EUwith ~~countries~~an ~~will~~amendment ~~depend~~to onthe ~~multiple~~collaboration ~~factors,~~agreement ~~including~~in August 2025 that (subject to an annual election by AstraZeneca) discontinued the ~~completion~~revenue and cost sharing provisions of ~~national~~the ~~reimbursement~~collaboration, ~~procedures~~and changed the payment structure. See Note 3 to the condensed consolidated financial statements for additional information.

Reblozyl (luspatercept-aamt) is a first-in-class erythroid maturation recombinant fusion protein that is being commercialized through a global collaboration with Bristol-Myers Squibb Company (BMS) (see Note 3 to the condensed consolidated financial statements). Reblozyl is approved for the treatment of anemia in certain rare blood disorders. Alliance revenue related to this collaboration (consisting of royalties) increased 3625% ~~and 39%~~ in the ~~third~~first quarter ~~and first nine months~~ of ~~2025,~~2026 ~~respectively,~~ primarily due to strong underlying sales performance.

Koselugo is an oral, selective MEK inhibitor approved for the treatment of patients with neurofibromatosis type 1 who have symptomatic inoperable plexiform neurofibromas. Koselugo is part of a collaboration with AstraZeneca. The increase in alliance revenue in both the third quarter and first nine months of 2025 is due to the recognition of a $150 million upfront payment and a $50 million milestone due to an amendment to the collaboration agreement that (subject to an annual election by AstraZeneca) discontinued the revenue and cost sharing provisions of the collaboration, and changed the payment structure. See Note 3 to the condensed consolidated financial statements for additional information.

- 38 -

Vaccines

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
	Three Months EndedMarch 31,						% Change Excluding ForeignExchange
($ in millions)	~~2025~~2026		~~2024~~2025		% Change				~~2025~~		~~2024~~		~~% Change~~
Gardasil/Gardasil 9	$	1,~~749~~069	$	21,~~306~~327	(2419)	%	(2522)	%	$	~~4,202~~	$	~~7,032~~	~~(40)~~	%	~~(40)~~	%
ProQuad	~~273~~198		~~274~~121		—64	%	~~(1)~~60	%	~~668~~		~~717~~		~~(7)~~	%	~~(7)~~	%
M-M-R II	~~123~~105		~~129~~168		(538)	%	(639)	%	~~387~~		~~346~~		12	%	12	%
Varivax	~~288~~235		~~301~~249		(46)	%	(57)	%	~~777~~		~~828~~		~~(6)~~	%	~~(6)~~	%
Vaxneuvance	~~226~~202		~~239~~230		(612)	%	(716)	%	~~685~~		~~647~~		6	%	6	%
Capvaxive	~~244~~142		47107		*33	%	*31	%	~~480~~		47		*		*

*In >January ~~100%~~2026, the acting director of the U.S. Centers for Disease Control and Prevention (CDC) announced changes to the child and adolescent immunization schedule (January announcement), reducing the number of routinely recommended vaccinations and creating three new categories: immunizations recommended for all children; immunizations recommended for certain high-risk groups or populations; and immunizations based on shared clinical decision-making. Immunizations recommended for all children include vaccines for measles, mumps, rubella, polio, pertussis, tetanus, diphtheria, Haemophilus influenzae type B (Hib), pneumococcal disease, human papillomavirus (HPV), and varicella (chickenpox). Immunizations recommended for certain high-risk groups or populations include respiratory syncytial virus (RSV), hepatitis A, hepatitis B, and dengue. Immunizations recommended based on shared clinical decision-making include rotavirus, hepatitis A, and hepatitis B. HHS has stated that immunizations for all of the diseases covered by the previous immunization schedule will still be available to anyone who wants them through Affordable Care Act insurance plans and federal insurance programs, including Medicaid, the Children’s Health Insurance Program, and the Vaccines For Children (VFC) program. Additionally, in September 2025, the trade association representing U.S. health insurers (AHIP) announced that its member health plans would continue to cover all immunizations that had been recommended by the CDC’s Advisory Committee on Immunization Practices (ACIP) as of September 1, 2025, with no cost-sharing for patients through the end of 2026. On March 16, 2026, a federal district court in Massachusetts issued a preliminary injunction staying, among other things, the immunization schedule changes in the CDC’s January announcement. The government is appealing the district court ruling to the U.S. Court of Appeals for the First Circuit.

Combined worldwide sales of Gardasil and Gardasil 9, vaccines to help prevent certain cancers and other diseases caused by certain types of ~~human papillomavirus (~~HPV), declined 2419% ~~and 40%~~ in the ~~third~~first quarter ~~and first nine months~~ of ~~2025, respectively~~2026. The sales ~~declines~~decline ~~were~~was primarily driven by lower demand in China (discussed below) and in Japan, reflecting in part that the last date to initiate the first dose in Japan’s national immunization program catch-up cohort was in March 2025. The ~~declines~~decline ~~were~~also ~~partially~~reflects ~~offset~~lower ~~by higher~~ sales in the U.S. primarily due to ~~higher~~unfavorable ~~net~~CDC ~~pricing~~purchasing patterns, ~~favorable~~partially ~~U.S.~~offset ~~Centers~~by ~~for~~higher ~~Disease~~net ~~Control~~pricing. ~~and~~As ~~Prevention~~previously ~~(CDC) purchasing patterns and~~disclosed, ~~for~~ the ~~year-to-date~~Company ~~period,~~suspended ~~higher~~shipments ~~demand.~~to InChina ~~the~~beginning ~~first~~in ~~nine~~February ~~months of~~ 2025, ~~higher~~given lower demand inand ~~certain~~elevated ~~international~~channel ~~markets~~inventory ~~also~~levels ~~partially~~in ~~offset the sales decline~~China. ~~Beginning~~In inApril ~~mid-2024~~2026, the Company ~~observed~~entered into a ~~significant~~revised ~~decline~~supply incontract ~~shipments~~with ~~from~~ its distributor and commercialization partner in China, Chongqing Zhifei Biological Products Co., Ltd. (Zhifei)~~, to disease and control prevention institutions and correspondingly into the points of vaccination compared with prior quarters of 2024, resulting in above normal inventory levels at Zhifei~~. ~~Accordingly,~~Subject ~~the Company shipped less than its contracted doses~~ to ~~Zhifei~~agreement inbetween the ~~latter part of 2024. Lower demand in China persisted and~~parties, at the ~~end of 2024, overall channel inventory levels in China remained elevated at above normal levels. Therefore, the~~ Company ~~made~~may amake ~~decision to temporarily pause~~ shipments to China ~~beginning~~ in ~~February 2025 and, given continued lower demand and elevated inventory levels in China, in mid-2025,~~ the ~~Company~~latter ~~determined~~part ~~it would not make any further shipments to China through at least the end~~ of ~~2025.~~2026; Asif ~~a result~~so, ~~combined~~any ~~sales~~associated ofrevenue ~~Gardasil/Gardasil 9 will decline significantly~~ in ~~2025~~2026 ~~compared~~is ~~with~~expected ~~2024. In January 2025, China’s NMPA approved Gardasil for use in males 9-26 years of age~~ to help prevent certain HPV-related cancers and diseases. In April 2025, China’s NMPA approved Gardasil 9 for use in males 16-26 years of age to help prevent certain HPV-related cancers and diseases. In May 2025, a nine-valent HPV vaccine produced by a local manufacturer received regulatory approval in China for use in females 9-45 years of age. In August 2025, the Company’s nine-valent HPV vaccine was approved for use in males nine years of age and older in Japan where it will be ~~marketed under the trademark Silgard 9~~immaterial.

Among the changes in the CDC’s now-stayed January announcement referenced above was a reduction of the recommended doses for HPV vaccination of adolescents to a single dose. Gardasil 9 is currently indicated in the U.S. for a two-dose regimen in adolescents aged 9-14 and a three-dose regimen for those aged 15-45. InPrevious ~~June 2024, the~~ CDC’s ~~Advisory~~recommendations ~~Committee~~for onadolescents ~~Immunization~~followed ~~Practices~~FDA-approved ~~(ACIP) announced the formation of an HPV vaccines workgroup~~dosing. InMany ~~October~~countries ~~2024,~~outside the ~~ACIP~~U.S. ~~workgroup~~have ~~stated~~implemented ~~that it intends to discuss and, potentially, vote on~~ a ~~change~~reduced todosing ~~the~~schedule ~~dose~~for ~~recommendation,~~HPV ~~which~~vaccination ~~could~~in ~~include~~certain aage ~~reduction~~groups. inThe ~~the~~Company ~~number~~anticipates ofthat ~~recommended~~any ~~doses.~~negative Aeffect ~~number~~ of ~~countries~~these ~~outside~~recommendations ~~the~~or ~~U.S.,~~reduced ~~predominately~~dosing ~~low-~~schedules ~~and~~on ~~middle-income~~sales ~~countries,~~of ~~have~~Gardasil/Gardasil ~~implemented~~9 awill ~~reduced~~not ~~dosing~~be ~~schedule for HPV vaccination~~material.

The Company is a party to license agreements pursuant to which the Company pays royalties on net sales of Gardasil/Gardasil 9. Under the terms of the more significant of these agreements, Merck pays a 7% royalty on net sales of ~~Gardasil/Gardasil 9 in the U.S.; this royalty expires in December 2028. The royalty expenses are included in Cost of sales.~~

Global sales of ProQuad (Measles, Mumps, Rubella and Varicella Virus Vaccine Live), a pediatric combination vaccine to help protect against measles, mumps, rubella and varicella, were relatively flat in the third quarter of 2025 and declined 7% in the first nine months of 2025. As a result of manufacturing delays, in January 2025, the Company borrowed doses of ProQuad from the CDC Pediatric Vaccine Stockpile (CDC Stockpile), which are being used to support routine vaccination in the U.S. The Company partially replenished the borrowing in the second quarter of 2025. The net effect of the borrowing and partial replenishment resulted in a $49 million reduction of ProQuad sales in the first nine months of 2025. Worldwide sales of M-~~M-R~~ II32 (Measles, Mumps and Rubella Virus Vaccine Live), a vaccine to help protect against measles, mumps and rubella, in the third quarter of 2025 were comparable to sales in the third quarter of 2024. Sales of M-M-R II grew 12% in the first nine months of 2025 primarily due to higher sales in the U.S. largely reflecting higher net pricing and increased demand due to measles outbreaks. Global sales of Varivax (Varicella Virus Vaccine Live), a vaccine to help prevent chickenpox (varicella), declined 4% and 6% in the third quarter and first nine months of 2025, respectively, primarily due to lower sales in the U.S. largely driven by lower demand and, for the year-to-date period, unfavorable CDC Stockpile activity, partially offset by higher net pricing. The unfavorable impact to Varivax sales from CDC Stockpile activity was offset by CDC Stockpile activity for other products as noted below. The Company has experienced manufacturing delays related to ProQuad and Varivax. As a result, the Company anticipates that some international markets will experience supply constraints during 2025.

InGardasil/Gardasil ~~September~~9 ~~2025,~~in the ~~ACIP~~U.S. ~~voted~~ to ~~recommend~~one ~~that~~third ~~children~~party ~~under the age of four years receive protection from varicella~~ (~~chickenpox)~~this asroyalty aexpires ~~standalone immunization rather than~~ in ~~combination~~December ~~with measles, mumps, and rubella (MMR~~2028) ~~vaccination~~. Previously, a combined measles, mumps, rubella and varicella virus (MMRV) vaccine could be used based on shared clinical decision-making between doctors and parents for the first dose, which was typically for children aged 12-15 months. The ~~ACIP~~royalty ~~also~~expenses ~~voted~~are ~~that~~included ~~MMRV~~in ~~will~~Cost ~~not be available for administration to children under the age~~ of ~~four years through~~ sales.

-Global 39sales of ProQuad (Measles, Mumps, Rubella and Varicella Virus Vaccine Live), a pediatric combination vaccine to help protect against measles, mumps, rubella and varicella, increased 64% in the first quarter of 2026 primarily due to higher sales in the U.S. As a result of manufacturing delays, in January 2025, the Company borrowed doses of ProQuad from the CDC Pediatric Vaccine Stockpile, which reduced sales of ProQuad by approximately $70 million in the first quarter of 2025. The Company replenished the borrowing later in 2025. Higher demand in certain European markets also contributed to the growth in ProQuad sales in the first quarter of 2026. Worldwide sales of M-M-R II (Measles, Mumps and Rubella Virus Vaccine Live), a vaccine to help protect against measles, mumps and rubella declined 38% in the first quarter of 2026 primarily due to lower sales in the U.S. largely reflecting unfavorable private sector purchasing patterns and lower demand. Global sales of Varivax (Varicella Virus Vaccine Live), a vaccine to help prevent chickenpox (varicella), declined 6% in the first quarter of 2026 primarily due to lower sales in the U.S. largely driven by lower demand, partially offset by higher net pricing.

In September 2025, the ~~Vaccines~~ACIP ~~for~~voted ~~Children~~to recommend that children under the age of four years receive protection from chickenpox (~~VFC~~varicella) ~~program.~~as ~~These~~a ~~provisional~~standalone ~~recommendations~~immunization ~~were~~rather ~~subsequently~~than ~~adopted~~in bycombination with measles, mumps, and rubella (MMR) vaccination, eliminating a previous shared clinical decision-making recommendation that allowed parents to choose combined MMR and varicella vaccine first-dose administration. The ACIP also voted to align the ~~interim~~VFC program with this change. The acting CDC Director ~~and~~adopted the recommendation in October 2025. These ACIP recommendations are ~~now~~subject ~~final~~to the federal district court’s March 16, 2026 preliminary injunction, as described above. MMR and varicella vaccines remain recommended and funded through the VFC program for both the first and second doses. The Company is the only manufacturer in the U.S. of MMRV vaccine (ProQuad) and varicella vaccine (Varivax). The Company anticipates that any negative effect of these recommendations toon sales of ProQuad will not be ~~immaterial~~material.

Worldwide sales of Vaxneuvance (Pneumococcal 15-valent Conjugate Vaccine), a vaccine to help protect against invasive pneumococcal disease caused by certain serotypes, declined 612% in the ~~third~~first quarter of ~~2025~~2026 primarily due to lower demand in ~~Japan due to competitive pressure, partially offset by higher demand in Europe. U.S. sales of Vaxneuvance were nearly flat in~~ the third quarter of 2025 as lower demand due to competitive pressure was largely offset by favorable public and private sector purchasing patterns. Worldwide sales of Vaxneuvance grew 6% in the first nine months of 2025 primarily due to public and private sector purchasing patterns in the U.S., ~~as well as higher demand in Europe~~ and ~~certain~~most ~~countries~~international inmarkets ~~the Asia Pacific region, partially offset by lower demand in the U.S. and Japan~~ due to ~~competitive pressure~~competition. U.S. Vaxneuvance sales in the first nine months of 2025 benefited from approximately $70 million of favorable CDC Stockpile activity, of which approximately $60 million was offset by a drawdown of CDC Stockpile inventory for Varivax (noted above) and RotaTeq (Rotavirus Vaccine, Live Oral, Pentavalent), which resulted in a net neutral transaction. Merck is a party to license agreements pursuant to which the Company pays royalties on net sales of Vaxneuvance. Under the ~~terms of the~~ most significant of these agreements, Merck pays a royalty of 7.25% on net sales of Vaxneuvance through 2026; this royalty will decline to 2.5% on net sales from 2027 through 2035. The royalty expenses are included in Cost of sales.

Sales of Capvaxive ~~were~~(Pneumococcal ~~$244~~21-valent ~~million~~Conjugate ~~and $480 million in the third quarter and first nine months of 2025~~Vaccine), ~~respectively,~~a ~~due~~vaccine ~~to continued uptake following launch in the U.S. in the third quarter of 2024, as well as seasonal inventory build. In June 2024, the FDA approved Capvaxive~~ for the prevention of invasive pneumococcal disease and pneumococcal pneumonia caused by certain serotypes in individuals 18 years of age and older., ~~Capvaxive~~grew ~~was~~33% ~~also approved~~ in the EUfirst inquarter ~~March~~of ~~2025~~2026 ~~and~~largely indue ~~Japan~~to inlaunch ~~August~~uptake ~~2025.~~in ~~The~~certain ~~timing~~international ofmarkets, ~~availability~~particularly ~~of Capvaxive~~ in ~~individual~~the EU, ~~countries~~and ~~will~~continued ~~depend~~uptake onin ~~multiple factors including~~ the ~~completion~~U.S. ofSales ~~reimbursement~~growth ~~procedures.~~in ~~The~~the U.S., ~~EU,~~was ~~and~~negatively ~~Japan~~impacted ~~approvals~~by ~~were~~a ~~supported~~reduction byin ~~results~~wholesaler ~~from~~inventory. Capvaxive was approved in the ~~STRIDE~~U.S. ~~clinical~~in ~~program~~June 2024, ~~which~~in ~~evaluated~~the ~~Capvaxive~~EU in ~~both~~March ~~vaccine-naïve~~2025 and ~~vaccine-experienced~~in ~~adult~~Japan ~~patient~~in ~~populations~~August 2025. Merck is a party to license agreements pursuant to which the Company pays royalties on net sales of Capvaxive. Under the terms of the most significant of these agreements, Merck pays a royalty of 7.25% on net sales of Capvaxive through 2026; this royalty will decline to 2.5% on net sales from 2027 through 2035. The royalty expenses are included in Cost of sales.

~~In June 2025, the FDA approved~~ Enflonsia (clesrovimab-cfor), is a preventive, long-acting monoclonal antibody, for the prevention of ~~respiratory syncytial virus (~~RSV) lower respiratory tract disease in neonates (newborns) and infants who are born during or entering their first RSV season. ~~The~~Enflonsia ~~FDA~~was ~~approval~~approved ~~was~~in ~~based~~the onU.S. in June 2025 and in the EU in April 2026 based on results from the ~~pivotal~~ CLEVER and SMART clinical trials. ~~Also~~The timing for availability of Enflonsia in ~~June~~individual ~~2025,~~EU ~~the~~countries ~~CDC’s~~will ~~ACIP~~vary ~~voted~~by tocountry ~~recommend~~and ~~Enflonsia~~depend ason anmultiple ~~option~~factors, ~~for~~including the ~~prevention~~completion of ~~RSV~~reimbursement ~~lower~~procedures. ~~respiratory~~Sales ~~tract~~of ~~disease~~Enflonsia inwere ~~infants~~$1 ~~younger~~million ~~than~~in ~~eight~~the ~~months~~first quarter of ~~age~~2026 ~~who~~and ~~are~~the ~~born~~Company ~~during~~expects orminimal ~~entering~~sales ~~their~~of ~~first~~Enflonsia ~~RSV~~in ~~season.~~the ~~These~~second ~~provisional~~quarter ~~recommendations~~of ~~were~~2026 ~~adopted~~given by the ~~CDC~~seasonal ~~Director~~nature ~~and~~of ~~are~~the ~~now~~product ~~official.~~and ~~The~~continued ~~CDC’s~~high ~~ACIP~~levels ~~also~~of ~~voted~~RSV tomonoclonal ~~include~~antibody ~~Enflonsia~~inventory in the ~~VFC~~market; ~~program.~~however, ~~Sales~~the ofCompany ~~Enflonsia~~anticipates inthat ~~the~~shipments ~~U.S.~~will ~~were~~increase ~~$79 million~~ in the ~~third~~second ~~quarter~~half of ~~2025 consisting of inventory stocking~~2026.

~~Hospital~~Cardiometabolic ~~Acute~~and ~~Care~~Respiratory

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
	Three Months EndedMarch 31,						% Change Excluding ForeignExchange
($ in millions)	~~2025~~2026		~~2024~~2025		% Change				~~2025~~		~~2024~~		~~% Change~~
Bridion	$	439	$	420	5	%	4	%	$	1,341	$	1,315	2	%	2	%
Winrevair	$	525	$	280	88	%	87	%
Prevymis	266		208		28	%	25	%	702		570		23	%	23	%
Ohtuvayre	131		—		—		—
Dificid	43		96		(55)	%	(55)	%	222		261		(15)	%	(15)	%
Alliance Revenue - Adempas/Verquvo (1)	109		106		3	%	3	%
Adempas	78		68		15	%	5	%

~~Worldwide sales of Bridion~~ (~~sugammadex~~1), ~~for~~Alliance ~~the~~revenue ~~reversal~~for ofAdempas ~~two types of neuromuscular blocking agents used during surgery, grew 5%~~ and 2%Verquvo inrepresents ~~the~~Merck’s ~~third~~share ~~quarter and first nine months~~ of ~~2025,~~profits ~~respectively,~~from assales ~~higher demand and net pricing~~ in ~~the~~Bayer ~~U.S.~~AG’s ~~was~~marketing ~~partially offset by lower demand in most international markets due to generic competition~~territories, ~~particularly~~which inare ~~Japan~~product ~~and the EU. The patents that provided market exclusivity for Bridion in the EU and Japan expired in July 2023 and January 2024, respectively. Accordingly, the Company is experiencing~~ sales ~~declines~~net of ~~Bridion~~cost inof ~~these~~sales ~~markets~~ and ~~expects~~commercialization ~~the~~costs ~~declines~~(see Note 3 to ~~continue. Bridion will lose market exclusivity in~~ the ~~U.S.~~condensed inconsolidated ~~July~~financial ~~2026; accordingly, the Company anticipates a significant decline in U~~statements).~~S. sales of Bridion thereafter.~~

~~Worldwide~~Winrevair ~~sales~~is ofan ~~Prevymis~~activin ~~(letermovir),~~signaling ainhibitor ~~medicine~~indicated for ~~prophylaxis~~the ~~(prevention)~~treatment of ~~cytomegalovirus~~adults with pulmonary arterial hypertension (~~CMV~~PAH) ~~infection~~(World ~~and~~Health ~~disease~~Organization in[WHO] ~~certain~~Group ~~high~~1 ~~risk~~pulmonary ~~adult~~hypertension) to improve exercise capacity and ~~pediatric~~WHO ~~recipients~~functional class, and reduce the risk of anclinical ~~allogenic~~worsening ~~hematopoietic~~events ~~stem~~including ~~cell~~hospitalization ~~transplant~~for PAH, lung transplantation and ~~for~~death. ~~prophylaxis~~Sales of ~~CMV~~Winrevair ~~disease~~rose into ~~certain~~$525 ~~high~~million ~~risk~~in ~~adult~~the ~~and~~first ~~pediatric~~quarter ~~recipients~~ of a2026 ~~kidney~~largely ~~transplant,~~due ~~grew~~to ~~28%~~continued ~~and~~uptake ~~23%~~ in the ~~third~~U.S. ~~quarter~~ and ~~first~~early ~~nine~~launch ~~months~~uptake ofin ~~2025,~~certain ~~respectively~~international markets, ~~primarily~~particularly ~~due~~in toJapan ~~higher~~and ~~demand~~Europe. Winrevair was originally approved in the U.S. ~~and~~in March 2024, in the ~~launch~~EU ofin ~~new~~August 2024, and in Japan in June 2025 (where it is being marketed as Airwin). Winrevair was approved for expanded indications in ~~certain~~PAH ~~international~~based ~~markets,~~on ~~partially~~the ~~offset~~ZENITH bytrial ~~lower~~in ~~demand~~the U.S. in ~~China~~October ~~due~~2025 toand ~~generic~~in ~~competition~~the EU in January 2026. Winrevair is the subject

~~Worldwide sales of Dificid (fidaxomicin), a medicine for the treatment of C. difficile~~-~~associated~~ ~~diarrhea,~~33 declined 55% and 15% in the third quarter and first nine months of 2025, respectively, primarily due to generic competition in the U.S. Dificid lost market exclusivity in the U.S. in July 2025; accordingly, the Company is experiencing a significant decline in U.S. sales of Dificid and expects the decline to continue.-

-of 40a -licensing agreement pursuant to which Merck pays a 22% royalty on net sales of Winrevair to BMS. The royalty expenses are included in Cost of sales.

~~Cardiovascular~~Ohtuvayre is an inhaled phosphodiesterases 3 and 4 (PDE3 and PDE4) inhibitor, which was approved in the U.S. in June 2024 for the maintenance treatment of chronic obstructive pulmonary disease (COPD) in adults. Ohtuvayre was obtained in conjunction with Merck’s October 2025 acquisition of Verona Pharma.

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
($ in millions)	2025		2024		% Change				2025		2024		% Change
Winrevair	$	360	$	149	*		*		$	976	$	219	*		*
Alliance Revenue - Adempas/Verquvo (1)	112		102		9	%	9	%	340		306		11	%	11	%
Adempas	82		72		14	%	7	%	229		214		7	%	5	%

Adempas (riociguat) and Verquvo (vericiguat) are part of a worldwide collaboration with Bayer AG (Bayer) to market and develop soluble guanylate cyclase (sGC) modulators (see Note 3 to the condensed consolidated financial statements). Adempas is approved for the treatment of certain types of PAH and chronic pulmonary hypertension. Verquvo is approved to reduce the risk of cardiovascular death and heart failure hospitalization following a hospitalization for heart failure or need for outpatient intravenous diuretics in adults with symptomatic chronic heart failure and reduced ejection fraction. Alliance revenue from the collaboration grew 3% in the first quarter of 2026 primarily reflecting higher demand in Bayer’s marketing territories. The Company expects alliance revenue to decline for the full year of 2026 reflecting the loss of market exclusivity for Adempas in the U.S. Revenue also includes sales of Adempas and Verquvo in Merck’s marketing territories. Sales of Adempas in Merck’s marketing territories increased 15% in the first quarter of 2026 largely due to higher demand.

*Infectious ~~> 100%~~Diseases

(1) Alliance revenue for Adempas and Verquvo represents Merck’s share of profits from sales in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs (see Note 3 to the condensed consolidated financial statements).


	Three Months Ended March 31,						% Change Excluding Foreign Exchange
($ in millions)	2026		2025		% Change
Bridion	$	472	$	441	7	%	7	%
Prevymis	272		208		31	%	26	%
Dificid	34		83		(59)	%	(59)	%
Lagevrio	28		102		(73)	%	(73)	%

~~Sales~~Global sales of ~~Winrevair~~Bridion ~~were~~(sugammadex), ~~$360~~for ~~million and $976 million in~~ the ~~third~~reversal ~~quarter~~of ~~and~~two ~~first~~types ~~nine months~~ of ~~2025,~~neuromuscular ~~respectively,~~blocking ~~largely~~agents ~~reflecting~~used ~~higher~~during ~~sales~~surgery, ingrew ~~the~~7% ~~U.S. due to continued uptake since launch~~ in the ~~second~~first quarter of ~~2024~~2026, ~~partially~~as ~~offset~~higher bydemand ~~lower net pricing~~ in the U.S. ~~(largely due to the Medicare Part D redesign that~~ was ~~part~~partially ofoffset ~~the~~by ~~IRA)~~lower ~~and~~demand ~~the timing of distributor purchases. Sales growth also reflects early launch uptake~~ in ~~certain~~most international markets, ~~particularly~~due into ~~the~~generic EUcompetition. ~~Following~~Bridion ~~initial~~will ~~approval~~lose bymarket ~~the~~exclusivity ~~FDA~~ in ~~March 2024 based on~~ the ~~STELLAR trial, in October 2025, the FDA approved an update to the~~ U.S. ~~product~~in ~~label~~July ~~based on the ZENITH trial~~2026. Winrevair is now indicated for the treatment of adults with pulmonary arterial hypertension (PAH) (World Health Organization [WHO] Group 1 pulmonary hypertension) to improve exercise capacity and WHO functional class (FC), and reduce the risk of clinical worsening events, including hospitalization for PAH, lung transplantation and death. The ~~recent~~Company ~~approval~~anticipates ~~expanded the indication to include components of the clinical worsening events: hospitalization for PAH, lung transplantation and death~~U.S. Insales ~~August 2024, the EC approved Winrevair, in combination with other PAH therapies, for the treatment~~ of ~~PAH~~Bridion ~~in adult patients with WHO FC II~~ to ~~III,~~decline ~~to improve exercise capacity based on the STELLAR trial. Winrevair has since launched in certain international markets~~thereafter, ~~including~~depending ~~certain~~upon ~~markets in~~ the ~~EU. Timing for commercial~~ availability of ~~Winrevair~~generic insupply. ~~the~~The ~~remaining~~Company EUexpects ~~countries will depend on multiple factors, including the completion of national reimbursement procedures, which is expected~~ to ~~occur~~discontinue ~~by the end of 2025 for most markets in the EU~~U. ~~In June 2025, Japan’s MHLW approved sotatercept for the treatment of adults with PAH where it will be marketed under the trademark Airwin~~S. ~~Winrevair is the subject of a licensing agreement pursuant to which Merck pays a 22% royalty on net~~ sales of ~~Winrevair~~Bridion toas ~~BMS.~~market ~~The~~supply ~~royalty~~stabilizes, ~~expenses~~potentially ~~are~~into ~~included in Cost of sales~~2027.

~~Adempas~~Worldwide ~~(riociguat)~~sales ~~and~~of ~~Verquvo~~Prevymis (~~vericiguat~~letermovir), ~~are part of~~ a ~~worldwide~~medicine ~~collaboration~~for ~~with~~prophylaxis ~~Bayer AG~~ (~~Bayer~~prevention) toof ~~market~~cytomegalovirus ~~and develop soluble guanylate cyclase~~ (~~sGC~~CMV) ~~modulators~~infection ~~(see~~and ~~Note 3~~disease toin ~~the condensed consolidated financial statements). Adempas is approved for the treatment of~~ certain ~~types~~high ofrisk ~~PAH~~adult and ~~chronic~~pediatric ~~pulmonary~~recipients ~~hypertension.~~of ~~Verquvo~~an isallogenic ~~approved~~hematopoietic tostem ~~reduce~~cell ~~the~~transplant ~~risk of cardiovascular death~~ and ~~heart failure hospitalization following a hospitalization~~ for ~~heart~~prophylaxis ~~failure~~of orCMV ~~need~~disease ~~for outpatient intravenous diuretics~~ in ~~adults~~certain ~~with~~high ~~symptomatic~~risk ~~chronic~~adult ~~heart failure~~ and ~~reduced~~pediatric ~~ejection~~recipients ~~fraction.~~of ~~Alliance~~a ~~revenue~~kidney ~~from~~transplant, ~~the collaboration~~ grew 931% ~~and 11%~~ in the ~~third~~first quarter ~~and first nine months~~ of ~~2025,~~2026 ~~respectively,~~ primarily ~~reflecting~~due to higher demand in ~~Bayer’s~~the ~~marketing territories~~U.S. ~~Revenue also includes sales of Adempas~~ and ~~Verquvo~~certain inEuropean ~~Merck’s~~markets, ~~marketing~~reflecting ~~territories. Sales of Adempas~~ in ~~Merck’s~~part ~~marketing territories increased 14% and 7% in~~ the ~~third~~launch ~~quarter and first nine months~~ of ~~2025,~~new ~~respectively, largely due to higher demand~~indications.

~~Virology~~Worldwide sales of Dificid (fidaxomicin), a medicine for the treatment of C. difficile-associated diarrhea, declined 59% in the first quarter of 2026 due to generic competition in the U.S. Dificid lost market exclusivity in the U.S. in July 2025; accordingly, the Company is experiencing a significant decline in U.S. sales of Dificid and expects the decline to continue.

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
($ in millions)	2025		2024		% Change				2025		2024		% Change
Lagevrio	$	138	$	383	(64)	%	(65)	%	$	323	$	843	(62)	%	(62)	%

Lagevrio is an investigational oral antiviral COVID-19 medicine being developed in a collaboration with Ridgeback Biotherapeutics LP (see Note 3 to the condensed consolidated financial statements). Sales of Lagevrio decreased 73% in the first quarter of 2026 largely due to lower demand in Japan and the U.S. driven primarily by declining COVID-19 cases. The Company expects the Lagevrio sales decline to continue during 2026.

~~Lagevrio~~In isApril an2026, ~~investigational~~the ~~oral~~FDA ~~antiviral~~approved ~~COVID~~Idvynso, a once-19daily, ~~medicine~~two-drug ~~being~~single-tablet ~~developed~~regimen inof doravirine, a ~~collaboration~~non-nucleoside ~~with~~reverse ~~Ridgeback~~transcriptase ~~Biotherapeutics~~inhibitor, LPand ~~(Ridgeback)~~islatravir, ~~(see~~a ~~Note 3~~next-generation tonucleoside ~~the~~analog ~~condensed~~reverse ~~consolidated~~transcriptase ~~financial~~inhibitor, ~~statements).~~for ~~Sales~~the treatment of ~~Lagevrio~~HIV-1 ~~decreased~~infection ~~64%~~in ~~and~~adults ~~62%~~to inreplace the ~~third~~current ~~quarter~~antiretroviral ~~and~~regimen ~~first~~in ~~nine~~those ~~months~~who are virologically suppressed (HIV-1 RNA less than 50 copies per mL) on a stable antiretroviral regimen with no history of ~~2025,~~virologic ~~respectively,~~treatment ~~largely~~failure ~~due~~and tono ~~lower~~known ~~demand~~substitutions inassociated ~~several~~with ~~markets~~resistance into ~~the~~doravarine. ~~Asia~~Idvynso ~~Pacific~~was ~~region,~~also ~~particularly~~approved in Japan, ~~and~~for these patients in ~~the~~March U2026.S. ~~driven~~The ~~primarily~~approvals bywere ~~declining~~based ~~COVID~~on the MK-198591A-051 ~~cases~~and MK-8591A-052 clinical trials.

Immunology

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
($ in millions)	2025		2024		% Change				2025		2024		% Change
Simponi	$	—	$	189	(100)	%	(100)	%	$	—	$	545	(100)	%	(100)	%
Remicade	—		41		(100)	%	(100)	%	—		115		(100)	%	(100)	%

Simponi and Remicade are treatments for certain inflammatory diseases that the Company marketed in Europe, Russia and Türkiye. The Company’s marketing rights with respect to these products reverted to Johnson & Johnson on October 1, 2024, subsequent to which the Company is no longer recognizing sales of these products.

- 41 -

Diabetes

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
	Three Months EndedMarch 31,						% Change Excluding ForeignExchange
($ in millions)	~~2025~~2026		~~2024~~2025		% Change				~~2025~~		~~2024~~		~~% Change~~
Januvia/Janumet	$	~~624~~574	$	~~482~~796	29(28)	%	(29)	%	$	~~2,043~~	$	~~1,781~~	15	%	16	%

Worldwide combined sales of Januvia and Janumet, medicines that help lower blood sugar levels in adults with type 2 diabetes, ~~grew~~declined 2928% ~~and 15%~~ in the ~~third~~first quarter ~~and first nine months~~ of ~~2025,~~2026 ~~respectively,~~ primarily due to ~~higher~~lower ~~net~~sales ~~pricing~~ in the U.S., ~~including~~reflecting alower ~~favorable~~net ~~true-up~~pricing toand ~~customer~~ongoing ~~discounts~~volume indeclines ~~the~~due ~~year-~~to~~-date~~ ~~period~~competitive pressure. ~~Sales~~The ~~growth~~sales indecline ~~both periods~~ was ~~partially~~also ~~offset~~attributable byto lower demand in China, and ongoing generic competition in most other international markets~~, and ongoing volume declines in the U~~.~~S. due to competitive pressure.~~

~~The~~While ~~American Rescue Plan Act enacted in~~ the key U.S. inpatent ~~2021~~for ~~included~~Januvia, aJanumet ~~provision~~and ~~that~~Janumet ~~eliminated~~XR claiming the ~~statutory~~sitagliptin ~~cap~~compound onexpired ~~rebates drug manufacturers pay to Medicaid beginning~~ in January ~~2024.~~2023, Asas a result of ~~this~~favorable ~~provision,~~court ~~the~~rulings ~~Company paid state Medicaid programs more in rebates than it received on Medicaid sales of Januvia, Janumet~~ and ~~Janumet~~settlement XRagreements inrelated ~~2024.~~to Ina ~~early~~later ~~2025,~~expiring ~~Merck~~patent ~~lowered~~directed ~~the list price of the Januvia family of products~~ to ~~more closely align them with net prices. The lower list price has reduced~~ the ~~rebate~~specific ~~amount Merck pays to Medicaid, resulting in higher realized net pricing. The Company expects higher U.S. net sales of these products for full year 2025 compared with full year 2024.~~

While the key U.S. patent for Januvia, Janumet and Janumet XR claiming the sitagliptin compound expired in January 2023, as a result of favorable court rulings and settlement agreements related to a later expiring patent directed to the specific sitagliptin salt form of the products (see Note 8 to the condensed consolidated financial statements), the Company expects that Januvia and Janumet will not lose market exclusivity in the U.S. until May 2026 and Janumet XR will not lose market exclusivity in the U.S. until July 2026, although a non-~~automatically~~ ~~substitutable~~34 form of sitagliptin that differs from the form in the Company’s sitagliptin products has been approved by the FDA. Additionally, in 2023, the U.S. Department of HHS, through the CMS, announced that Januvia would be included in the first year of the IRA’s Program. Pursuant to the IRA’s Program, a government price was set for Januvia, which will become effective on January 1, 2026. Also, in January 2025, the U.S. Department of HHS, through the CMS, announced that Janumet and Janumet XR would be included in the second year of the IRA’s Program, with government price setting to become effective on January 1, 2027. The Company has sued the U.S. government regarding the IRA’s Program. As a result of the anticipated patent expiries in 2026, the government price setting to take effect in 2026 and 2027 noted above, as well as ongoing competitive pressure, the Company anticipates significant sales declines for Januvia, Janumet and Janumet XR in the U.S. in 2026 and thereafter.-

sitagliptin salt form of the products, Januvia and Janumet will lose market exclusivity in the U.S. in May 2026 and Janumet XR will lose market exclusivity in the U.S. in July 2026, although a non-automatically substitutable form of sitagliptin that differs from the form in the Company’s sitagliptin products has been approved by the FDA. See Note 8 to the condensed consolidated financial statements for additional information related to the above-referenced patent litigation. Additionally, HHS, through the CMS, selected Januvia in 2023 for the first year of the IRA’s Program, and selected Janumet and Janumet XR in 2025 for the second year of the IRA’s Program. Pursuant to the IRA’s program, the government set a price for Januvia, which became effective on January 1 2026, and set a price for Janumet and Janumet XR, which will become effective on January 1, 2027. The Company has sued the U.S. government regarding the IRA’s Program. The Company expects a significant decline in sales of Januvia in the first half of 2026 and subsequently, following loss of market exclusivity in May 2026, the Company anticipates it will lose nearly all U.S. sales of Januvia and Janumet.

Animal Health Segment

	Three Months EndedSeptember 30,						% Change Excluding ForeignExchange		Nine Months EndedSeptember 30,						% Change Excluding ForeignExchange
	Three Months EndedMarch 31,						% Change Excluding ForeignExchange
($ in millions)	~~2025~~2026		~~2024~~2025		% Change				~~2025~~		~~2024~~		~~% Change~~
Livestock	$	1,~~023~~064	$	~~886~~924	1615	%	148	%	$	~~2,909~~	$	~~2,573~~	13	%	15	%
Companion Animal	~~592~~727		~~601~~664		~~(2)~~9	%	~~(3)~~4	%	~~1,940~~		~~1,907~~		2	%	2	%
	$	1,~~615~~791	$	1,~~487~~588	913	%	76	%	$	~~4,849~~	$	~~4,480~~	8	%	10	%

Sales of livestock products grew 1615% ~~and 13%~~ in the ~~third~~first quarter ~~and first nine months~~ of ~~2025,~~2026 ~~respectively,~~ primarily due to higher demand ~~across~~for ~~all~~ruminant ~~species~~and poultry products, as well as higher pricing. ~~Sales growth in 2025 also benefited from the inclusion of sales from the July 2024 acquisition of the aqua business of Elanco Animal Health Incorporated.~~

Sales of companion animal products ~~declined~~grew 29% in the ~~third~~first quarter of ~~2025~~2026 primarily due to ~~lower~~new ~~demand,~~product ~~reflecting~~launches ~~a reduction in veterinary visits~~ and ~~competitive~~higher ~~pressure for parasiticides~~pricing, partially offset by ~~higher~~lower ~~pricing,~~demand ~~improved~~for ~~supply~~other ~~and new product launches. Sales of companion animal~~ products ~~grew 2%~~ in the ~~first nine months of 2025 due to higher pricing and improved supply~~portfolio, ~~partially~~reflecting ~~offset~~a byreduction ~~lower~~in ~~demand~~veterinary visits. Sales of the Bravecto (fluralaner) line of products were $~~262~~379 million in the ~~third~~first quarter of ~~2025~~2026, representing agrowth ~~decline~~ of 116%, or 39% excluding the effect of foreign exchange, compared with the ~~third~~first quarter of ~~2024. Sales of Bravecto were $925 million for the first nine months of~~ 2025~~, essentially flat compared with the corresponding prior year period, both nominally and excluding the effect of foreign exchange~~.

In ~~July~~February ~~2025~~2026, the FDA approved ~~Bravecto~~Numelvi ~~Quantum~~ (~~fluralaner~~atinvicitinib ~~for extended-release injectable suspension~~tablets), athe ~~once-yearly~~first ~~injectable product to treat~~ and ~~protect~~only ~~dogs from fleas and ticks. Also in July 2025, the EC approved Numelvi (atinvicitinib) tablets for dogs, a once-daily,~~ second-generation Janus kinase (JAK) inhibitor indicated for the ~~treatment~~control of pruritus associated with allergic dermat

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