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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q

(Mark One)


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

For the quarterly period ended September 30, 2025


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

For the transition period from ________________ to ________________

Commission File Number: 001-39509

Dyne Therapeutics, Inc.

(Exact Name of Registrant as Specified in its Charter)


Delaware	36-4883909
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
1560 Trapelo Road Waltham, Massachusetts	02451
(Address of principal executive offices)	(Zip Code)

(781) 786-8230

(Registrant’s telephone number, including area code)

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, $0.0001 par value per share

     DYN

     Nasdaq Global Select Market

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, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

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 ☒

As of October 31, 2025, the registrant had 142,824,687 shares of common stock, $0.0001 par value per share, outstanding.

Table of Contents


		Page
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS		2
PART I.	FINANCIAL INFORMATION	5
Item 1.	Financial Statements (Unaudited)	5
	Condensed Consolidated Balance Sheets	5
	Condensed Consolidated Statements of Operations and Comprehensive Loss	6
	Condensed Consolidated Statements of Stockholders’ Equity	7
	Condensed Consolidated Statements of Cash Flows	8
	Notes to Unaudited Condensed Consolidated Financial Statements	9
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	20
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	33
Item 4.	Controls and Procedures	33
PART II.	OTHER INFORMATION	33
Item 1.	Legal Proceedings	33
Item 1A.	Risk Factors	33
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	97
Item 3.	Defaults Upon Senior Securities	97
Item 4.	Mine Safety Disclosures	97
Item 5.	Other Information	97
Item 6.	Exhibits	98
Signatures		99

We own or have rights to trademarks, service marks and trade names that we use in connection with the operation of our business, including our corporate name, logos and website names. The service marks and trademarks that we own include the marks Dyne Therapeutics® and FORCE™. Other trademarks, service marks and trade names appearing in this Quarterly Report on Form 10-Q are the property of their respective owners. Solely for convenience, some of the trademarks, service marks and trade names referred to in this Quarterly Report on Form 10-Q are listed without the ® and ™ symbols, but we will assert, to the fullest extent under applicable law, our rights to our trademarks, service marks and trade names.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q, or this Quarterly Report, contains forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act and Section 21E of the Securities Exchange Act of 1934, as amended, that involve substantial risk and uncertainties. All statements other than statements of historical fact, contained in this Quarterly Report, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans and objectives of management, are forward-looking statements. The words “anticipate,” “believe,” “continue” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would,” or the negative of these words or other similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

The forward-looking statements in this Quarterly Report include, among other things, statements about:

•

the initiation, timing, design, progress and results of our research and development programs, preclinical studies and clinical trials;

•

the anticipated timing of the submission and clearance of investigational new drug applications, or INDs, and comparable foreign applications for any product candidates we may develop;

•

the timing of and our ability to submit applications for, obtain and maintain regulatory approvals for any product candidates we may develop;

•

our estimates regarding expenses, future revenue, capital requirements, need for additional financing and the period over which we believe our cash, cash equivalents and marketable securities will be sufficient to fund our operating expenses, debt service obligations and capital expenditure requirements;

•

our ability to comply with restrictive covenants under our loan agreement with Hercules Capital, Inc., or Hercules;

•

our ability to satisfy interest and principal payments under our loan agreement with Hercules;

•

our plans to develop and, if approved, subsequently commercialize any product candidates we may develop;

•

the potential advantages of our FORCE platform;

•

our commercialization, marketing and manufacturing capabilities and strategy;

•

our intellectual property position and our expectations regarding our ability to obtain and maintain intellectual property protection;

•

our ability to identify additional products, product candidates or technologies with significant commercial potential that are consistent with our commercial objectives;

•

the impact of government laws and regulations;

•

our competitive position and expectations regarding developments and projections relating to our competitors and any competing therapies that are or become available; and

•

our ability to establish and maintain collaborations or obtain additional funding.

We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. We have included important factors in this Quarterly Report, particularly in Item 1A. “Risk Factors” in this Quarterly Report, that we believe could cause actual results or events to differ materially from the forward-looking statements that we make. Moreover, we operate in a competitive and rapidly changing environment. New risk factors and uncertainties may emerge from time to time, and it is not possible for management to predict all risk factors and uncertainties, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, collaborations, joint ventures or investments we may make or enter into.

You should read this Quarterly Report and the documents that we have filed or incorporated by reference as exhibits to this Quarterly Report with the understanding that our actual future results may be materially different from what we expect. The forward-looking statements contained in this Quarterly Report are made as of the date of this Quarterly Report, and we do not assume any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by applicable law.

RISK FACTOR SUMMARY

Our business is subject to a number of risks that, if realized, could materially affect our business, prospects, operating results and financial condition. These risks are discussed more fully in the “Risk Factors” section of this Quarterly Report. These risks include, but are not limited to, the following:

•

we will need substantial additional funding. If we are unable to raise capital when needed, we could be forced to delay, reduce or eliminate our product development programs or commercialization efforts;

•

our product candidates are in varying stages of preclinical and clinical development, and we have not completed clinical development of any product candidate. We do not expect to complete the commercialization of any product candidate at least until 2027, if ever. If we are unable to advance product candidates through preclinical studies and clinical trials, obtain marketing approval and ultimately commercialize them, or experience significant delays in doing so, our business will be materially harmed;

•

we may encounter substantial delays in commencement, enrollment or completion of our clinical trials and the data from the clinical trials of our product candidates may fail to demonstrate sufficient safety and efficacy to warrant further development or satisfy the applicable regulatory authorities, which could prevent us from commercializing any product candidates we determine to develop on a timely basis, if at all;

•

our approach to the discovery and development of product candidates based on our FORCE platform is unproven, and we may not be successful in our efforts to develop our product candidates;

•

the outcome of preclinical studies and initial data from earlier-stage clinical trials may not be predictive of final results of clinical trials or future clinical trials and data from trials in one indication may not be predictive of results of clinical trials in other indications;

•

if our product candidates cause undesirable side effects or have other unexpected adverse properties, such side effects or properties could delay or prevent us from conducting clinical trials or seeking or obtaining regulatory approval, limit the commercial potential of our product candidates or result in significant negative consequences to the extent such effects or adverse properties are observed following any marketing approval;

•

our loan agreement with Hercules contains restrictive and financial covenants that may limit our operating flexibility and our failure to comply with the covenants or other terms of the loan agreement, including as a result of events beyond our control, could result in a default under the loan agreement that could materially and adversely affect our business;

•

we rely, and expect to continue to rely, on third parties to conduct some or all aspects of our product manufacturing, research, preclinical and clinical testing, and these third parties may not perform satisfactorily;

•

we face substantial competition, which may result in others discovering, developing or commercializing products before us or more successfully than we do;

•

our rights to develop and commercialize certain of our product candidates are subject or may in the future be subject, in part, to the terms and conditions of licenses granted to us by third parties. If we fail to comply with our obligations under current or future intellectual property license agreements or otherwise experience disruptions to our business relationships with our current or any future licensors, we could lose intellectual property rights that are important to our business; and

•

if we or our licensors are unable to obtain, maintain and defend patent and other intellectual property protection for any product candidates or technology, or if the scope of the patent or other intellectual property protection obtained is not sufficiently broad, our competitors could develop and commercialize products and technology similar or identical to ours, and our ability to successfully develop and commercialize our product candidates or our technology may be adversely affected due to such competition.

PART I—FINANCIAL INFORMATION

Item 1. Condensed Consolidated Financial Statements (Unaudited)

Dyne Therapeutics, Inc.

Condensed Consolidated Balance Sheets (Unaudited)

(in thousands, except share and per share data)


	September 30,			December 31,
	2025			2024
Assets
Current assets:
Cash and cash equivalents	$	573,610		$	435,449
Marketable securities		218,277			206,819
Prepaid expenses and other current assets		14,376			17,011
Total current assets		806,263			659,279
Property and equipment, net		23,972			5,398
Right-of-use assets		21,818			24,615
Restricted cash and other assets		15,006			1,942
Total assets	$	867,059		$	691,234
Liabilities and Stockholders’ Equity
Current liabilities:
Accounts payable		12,061			6,562
Accrued expenses and other current liabilities		42,749			30,846
Lease liabilities		5,039			4,850
Total current liabilities		59,849			42,258
Long-term debt, net		99,147			—
Lease liabilities, net of current portion		16,280			19,138
Total liabilities		175,276			61,396
Stockholders’ equity
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at September 30, 2025 and December 31, 2024		—			—
Common stock, $0.0001 par value; 200,000,000 shares authorized at September 30, 2025 and December 31, 2024; 142,613,248 and 102,318,629 shares issued and outstanding at September 30, 2025 and December 31, 2024, respectively		14			10
Additional paid-in capital		1,975,460			1,579,750
Accumulated other comprehensive loss		496			6
Accumulated deficit		(1,284,187	)		(949,928	)
Total stockholders’ equity		691,783			629,838
Total liabilities and stockholders’ equity	$	867,059		$	691,234

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

Dyne Therapeutics, Inc.

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited)

(in thousands, except share and per share data)


	Three Months Ended September 30,						Nine Months Ended September 30,
	2025			2024			2025			2024
Operating expenses:
Research and development	$	97,219		$	92,800		$	302,902		$	199,601
General and administrative		16,673			12,859			49,153			47,177
Total operating expenses		113,892			105,659			352,055			246,778
Loss from operations		(113,892	)		(105,569	)		(352,055	)		(246,778	)
Other income (expense):
Interest income		8,476			9,276			22,202			19,330
Interest expense		(2,904	)		—			(2,998	)		—
Other income (expense), net		279			(742	)		(1,408	)		(428	)
Total other income (expense), net		5,851			8,534			17,796			18,902
Net loss	$	(108,041	)	$	(97,125	)	$	(334,259	)	$	(227,876	)
Net loss per share—basic and diluted	$	(0.76	)	$	(0.96	)	$	(2.74	)	$	(2.49	)
Weighted average common shares outstanding, basic and diluted		141,810,881			100,882,042			121,980,400			91,511,621
Comprehensive loss:
Net loss	$	(108,041	)	$	(97,125	)	$	(334,259	)	$	(227,876	)
Other comprehensive loss:
Unrealized gains on marketable securities, net		244			718			490			478
Comprehensive loss	$	(107,797	)	$	(96,407	)	$	(333,769	)	$	(227,398	)

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

Dyne Therapeutics, Inc.

Condensed Consolidated Statements of Stockholders’ Equity (Unaudited)

(in thousands, except share data and issuance costs)


	Common Stock				Additional Paid-In		Accumulated Other			Accumulated			Stockholders’
	Shares		Amount		Capital		Comprehensive Loss			Deficit			Equity
Balance at January 1, 2025		102,318,629	$	10	$	1,579,750	$	6		$	(949,928	)	$	629,838
Issuance of common stock in at-the-market offering, net of issuance costs of $4.4 million		10,660,159		1		140,652		—			—			140,653
Exercise of stock options		89,835		—		588		—			—			588
Stock-based compensation		—		—		13,020		—			—			13,020
Vesting of restricted stock units		565,159		—		—		—			—			—
Unrealized gains on marketable securities		—		—		—		235			—			235
Net loss		—		—		—		—			(115,361	)		(115,361	)
Balance at March 31, 2025		113,633,782	$	11	$	1,734,010	$	241		$	(1,065,289	)	$	668,973
Exercise of stock options		488,457		—		2,795		—			—			2,795
Stock-based compensation		—		—		10,523		—			—			10,523
Vesting of restricted stock units		216,371		—		—		—			—			—
Unrealized gains on marketable securities		—		—		—		11			—			11
Net loss		—		—		—		—			(110,857	)		(110,857	)
Balance at June 30, 2025		114,338,610	$	11	$	1,747,328	$	252		$	(1,176,146	)	$	571,445
Issuance of common stock in public offering, net of issuance costs of $14.1 million		27,878,788		3		215,800		—			—			215,803
Exercise of stock options		151,492		—		1,250		—			—			1,250
Stock-based compensation		—		—		11,082		—			—			11,082
Vesting of restricted stock units		244,358		—		—		—			—			—
Unrealized gains on marketable securities		—		—		—		244			—			244
Net loss		—		—		—		—			(108,041	)		(108,041	)
Balance at September 30, 2025		142,613,248	$	14	$	1,975,460	$	496		$	(1,284,187	)	$	691,783


	Common Stock				Additional Paid-In		Accumulated Other			Accumulated			Stockholders’
(in thousands, except per share data)	Shares		Amount		Capital		Comprehensive Loss			Deficit			Equity
Balance at January 1, 2024		61,468,743	$	6	$	723,796	$	—		$	(632,510	)	$	91,292
Issuance of common stock in public offering, net of issuance costs of $21.3 million		19,722,500		2		323,849		—			—			323,851
Issuance of common stock in at-the-market offering, net of issuance costs of $3.3 million		3,800,465		1		97,870		—			—			97,871
Exercise of stock options		1,858,791		—		10,916		—			—			10,916
Stock-based compensation		—		—		19,906		—			—			19,906
Vesting of restricted stock units		239,150		—		—		—			—			—
Unrealized losses on marketable securities		—		—		—		(132	)		—			(132	)
Net loss		—		—		—		—			(65,649	)		(65,649	)
Balance at March 31, 2024		87,089,649	$	9	$	1,176,337	$	(132	)	$	(698,159	)	$	478,055
Issuance of common stock in public offering, net of issuance costs of $23.0 million		12,075,000		1		351,328		—			—			351,329
Exercise of stock options		564,904		—		4,283		—			—			4,283
Stock-based compensation		—		—		6,736		—			—			6,736
Vesting of restricted stock units		389,965		—		—		—			—			—
Unrealized losses on marketable securities		—		—		—		(108	)		—			(108	)
Net loss		—		—		—		—			(65,102	)		(65,102	)
Balance at June 30, 2024		100,119,518	$	10	$	1,538,684	$	(240	)	$	(763,261	)	$	775,193
Exercise of stock options		1,388,613		—		18,009		—			—			18,009
Stock-based compensation		—		—		8,745		—			—			8,745
Vesting of restricted stock units		245,247		—		—		—			—			—
Unrealized gains on marketable securities		—		—		—		718			—			718
Net loss		—		—		—		—			(97,125	)		(97,125	)
Balance at September 30, 2024		101,753,378	$	10	$	1,565,438	$	478		$	(860,386	)	$	705,540

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

Dyne Therapeutics, Inc.

Condensed Consolidated Statements of Cash Flows (Unaudited)

(in thousands)


	Nine Months Ended September 30,
	2025			2024
Cash flows from operating activities:
Net loss	$	(334,259	)	$	(227,876	)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense		34,625			35,387
Depreciation and amortization expense		1,528			1,223
Non-cash lease expense		128			434
Non-cash interest expense		62			—
Accretion of premium on marketable securities		(1,447	)		(2,768	)
Loss (gain) on sale of marketable securities		(14	)		(26	)
Loss (gain) on disposal of property and equipment		95			(2	)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets		3,184			(6,442	)
Other non-current assets		(12,991	)		—
Accounts payable and other liabilities		17,714			(7,964	)
Net cash used in operating activities		(291,375	)		(208,034	)
Cash flows from investing activities:
Purchases of property and equipment		(1,436	)		(1,301	)
Advance payment for long-lead equipment		(18,790	)		—
Purchases of marketable securities		(153,823	)		(264,729	)
Maturities of marketable securities		135,847			76,215
Sales of marketable securities		8,469			1,749
Net cash used in investing activities		(29,733	)		(188,066	)
Cash flows from financing activities:
Proceeds from issuance of common stock in public offering, net of issuance costs		215,803			675,180
Proceeds from issuance of common stock in at-the-market offering, net of issuance costs		140,653			97,871
Proceeds from exercise of stock options		4,633			33,208
Proceeds from issuance of long-term debt, net of issuance costs paid		98,802			—
Payment of debt issuance costs		(549	)		—
Net cash provided by financing activities		459,342			806,259
Net increase (decrease) in cash, cash equivalents and restricted cash		138,234			410,159
Cash, cash equivalents and restricted cash, beginning of period		437,391			123,941
Cash, cash equivalents and restricted cash, end of period	$	575,625		$	534,100
Supplemental disclosures of cash flow information:
Purchase of property and equipment in accounts payable	$	—		$	48
Cash paid for interest		1,824			—

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

Dyne Therapeutics, Inc.

Notes to Condensed Consolidated Financial Statements (Unaudited)

1. Nature of Business and Basis of Presentation

Dyne Therapeutics, Inc. (the “Company”) is a clinical-stage neuromuscular disease company focused on delivering functional improvement for people living with genetically driven neuromuscular diseases. The Company was incorporated in Delaware on December 1, 2017 and has a principal place of business in Waltham, Massachusetts.

The Company is subject to risks and uncertainties common to clinical-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval for its product candidates, fluctuations in operating results, compliance with government regulations, the ability to establish clinical- and commercial-scale manufacturing processes and the ability to secure additional capital to fund operations. Product candidates and programs currently under development require significant research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s development efforts are successful and product candidates receive regulatory approval, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

The accompanying condensed consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets and the satisfaction of liabilities and commitments in the ordinary course of business. Since inception, the Company has funded its operations with proceeds from the sales of equity securities, and its initial borrowing under its Loan and Security Agreement (the “Loan Agreement”) with Hercules Capital, Inc. (“Hercules”). The Company expects to continue to generate operating losses for the foreseeable future. The Company expects that its cash, cash equivalents, and marketable securities will be sufficient to fund its operating expenses, debt service obligations and capital expenditure requirements for at least 12 months from the issuance of these condensed consolidated financial statements.

To continue its development efforts, the Company will need to obtain substantial additional funding through public or private equity offerings, debt financings, collaborations, strategic alliances and/or licensing arrangements in order to fund its research and development and ongoing operating expenses. The Company may not be able to obtain financing on acceptable terms, when needed or at all, and the Company may not be able to enter into collaborations, strategic alliances or licensing arrangements. The terms of any financing may adversely affect the holdings or the rights of the Company’s stockholders. Any collaborations, strategic alliances or licensing arrangements may require the Company to relinquish rights to certain of its technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to the Company. If the Company is unable to obtain funding, the Company could be forced to delay, limit, reduce or eliminate some or all of its research and development programs, pipeline expansion or future commercialization efforts or grant rights to develop and market product candidates, which could adversely affect its business prospects. Although management will continue to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations when needed or at all.

2. Summary of Significant Accounting Policies

The accompanying condensed consolidated financial statements reflect the operations of the Company and the Company’s wholly-owned subsidiary, Dyne Therapeutics Securities Corporation. Intercompany balances and transactions have been eliminated in consolidation. The accompanying condensed consolidated financial statements have been prepared in conformity with generally accepted accounting principles (“GAAP”) in the United States of America. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

The financial statements of the Company included herein have been prepared, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The unaudited interim financial statements have been prepared on the same basis as audited annual financial statements, except certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted from this report, as is permitted by such rules and regulations. In the opinion of management, the interim financial information reflects all adjustments, all of which are of a normal and recurring nature, necessary for a fair representation

of the results for the reported periods. Accordingly, these financial statements should be read in conjunction with the financial statements and notes thereto included in the Company’s annual report on Form 10-K filed with the SEC on February 27, 2025. The results for the three and nine months ended September 30, 2025 are not necessarily indicative of results to be expected for the year ending December 31, 2025, any other interim periods, or any future year or period.

Fair value measurements

Certain assets and liabilities are carried at fair value. 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. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

•

Level 1—Unadjusted quoted prices in active markets that are accessible to the reporting entity at the measurement date for identical assets and liabilities.

•

Level 2—Inputs other than quoted prices in active markets for identical assets and liabilities that are observable either directly or indirectly for substantially the full term of the asset or liability. Level 2 inputs include the following:

•

quoted prices for similar assets and liabilities in active markets;

•

quoted prices for identical or similar assets or liabilities in markets that are not active;

•

observable inputs other than quoted prices that are used in the valuation of the asset or liabilities (e.g., interest rate and yield curve quotes at commonly quoted intervals); and

•

inputs that are derived principally from or corroborated by observable market data by correlation or other means.

•

Level 3—Unobservable inputs for the assets or liability (i.e., supported by little or no market activity). Level 3 inputs include management’s own assumptions about the assumptions that market participants would use in pricing the asset or liability (including assumptions about risk).

Net loss per share

Basic net loss per share is computed by dividing the net loss by the weighted average number of shares of common stock outstanding for the period. Diluted net loss is computed by adjusting net loss to reallocate undistributed earnings based on the potential impact of dilutive securities. Diluted net loss per share is computed by dividing the diluted net loss by the weighted average number of shares of common stock outstanding for the period, including potential dilutive common shares assuming the dilutive effect of common stock equivalents.

The following potentially dilutive common stock equivalents, presented based on amounts outstanding at each period end, were excluded from the computation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect:


	September 30,
	2025		2024
Options to purchase common stock		9,649,402		7,743,732
Unvested restricted stock units		2,591,337		2,718,092
Total		12,240,739		10,461,824

Recently Issued Accounting Pronouncements Not Yet Adopted

In November 2024, the FASB issued ASU 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Topic 220-40) ("ASU 2024-03"). The amendments in this update require new disclosures to disaggregate prescribed natural expenses underlying any income statement caption. ASU 2024-03 is effective for annual periods in fiscal years beginning after December 15, 2026, and interim periods thereafter. Early adoption is permitted. ASU 2024-03 applies on a prospective basis for periods beginning after the effective date. However, retrospective application to any or all prior periods presented is permitted. The Company is currently assessing the impact ASU 2024-03 will have on the condensed consolidated financial statements and disclosures.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740) ("ASU 2023-09"). The amendments in this update require enhanced annual income tax disclosures for the effective tax rate reconciliation and income taxes paid. The amendments are effective for public business entities for annual periods beginning after December 15, 2024 and for annual periods beginning after December 15, 2025 for all other entities. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. ASU 2023-09 applies on a prospective basis to annual financial statements for periods beginning after the effective date. However, retrospective application in all prior periods presented is permitted. The Company is assessing what impact ASU 2023-09 will have on the condensed consolidated financial statements and disclosures.

In July 2025, the One Big Beautiful Bill Act (“OBBBA”) was enacted. The OBBBA makes permanent key elements of the Tax Cuts and Jobs Act of 2017, including 100% bonus depreciation, domestic research cost expensing and the business interest expense limitation, among other tax changes. The new legislation has multiple effective dates, with certain provisions effective in 2025 and others in the future. In accordance with ASC 740, Accounting for Income Taxes, the impacts of the OBBBA did not affect the Company’s U.S. deferred tax assets or liabilities, as the Company continues to maintain a full valuation allowance against those balances.

3. Cash, Cash Equivalents and Restricted Cash

Cash includes cash in readily available checking accounts and cash equivalents include money market funds that invest in U.S. treasury securities and all highly liquid investments maturing within 90 days from the date of purchase.

Amounts included in restricted cash represent amounts pledged as collateral for letters of credit required for security deposits on the Company’s leased facilities.

Cash, cash equivalents and restricted cash consisted of the following:


	September 30,		December 31,
(in thousands)	2025		2024
Cash and cash equivalents	$	573,610	$	435,449
Restricted cash		2,015		1,942
Total	$	575,625	$	437,391

4. Fair Value Measurements

The following tables set forth marketable securities for the periods presented:


	As of September 30, 2025
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Total
Commercial paper		9,244		9		—			9,253
Corporate debt securities		169,435		367		(4	)		169,798
Certificates of deposit		15,720		10		—			15,730
U.S. treasury notes		23,382		114		—			23,496
Total	$	217,781	$	500	$	(4	)	$	218,277


	As of December 31, 2024
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Total
Commercial paper		14,203		8		—			14,211
Corporate debt securities		162,078		131		(114	)		162,095
Certificates of deposit		9,369		4		(1	)		9,372
U.S. treasury notes		21,163		7		(29	)		21,141
Total	$	206,813	$	150	$	(144	)	$	206,819

The following tables set forth by level, within the fair value hierarchy (see Note 2), the assets carried at fair value on a recurring basis for the periods presented:


	Fair Value Measurements as of September 30, 2025
(in thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents
Money market funds	$	179,870	$	—	$	—	$	179,870
Marketable securities
Commercial paper		—		9,253		—		9,253
Corporate debt securities		—		169,798		—		169,798
Certificates of deposit		—		15,730		—		15,730
U.S. treasury notes		23,496		—		—		23,496
Total	$	203,366	$	194,781	$	—	$	398,147


	Fair Value Measurements as of December 31, 2024
(in thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents
Money market funds	$	3,535	$	—	$	—	$	3,535
Marketable securities
Commercial Paper		—		14,211		—		14,211
Corporate debt securities		—		162,095		—		162,095
Certificates of deposit		—		9,372		—		9,372
U.S. treasury notes		21,141		—		—		21,141
Total	$	24,676	$	185,678	$	—	$	210,354

The fair value of U.S. government treasury notes and money market funds were determined by the Company based on quoted market prices, which represent a Level 1 measurement within the fair value hierarchy. Commercial paper, certificates of deposit, and corporate debt securities were valued by the Company using quoted prices in active markets for similar securities, which represent a Level 2 measurement within the fair value hierarchy.

There were no transfers between Level 1, Level 2, or Level 3 during the periods presented.

The following table summarizes the scheduled maturity for the Company's marketable securities for the periods presented:


(in thousands)	September 30, 2025
Maturing in one year or less	$	147,397
Maturing after one year through two years		70,880
Maturing after two years		—
Total	$	218,277

Financial instruments not recorded at fair value

The carrying values of cash, cash equivalents, accounts payable and accrued expenses that are reported on the balance sheets approximate their fair value due to the short-term nature of these assets and liabilities.

5. Property and Equipment

Property and equipment consisted of the following:


	September 30,			December 31,
(in thousands)	2025			2024
Laboratory equipment	$	10,897		$	9,197
Office and computer equipment		2,486			2,355
Construction in process		18,790			619
Property and equipment—at cost		32,173			12,171
Less accumulated depreciation and amortization		(8,201	)		(6,773	)
Property and equipment—net	$	23,972		$	5,398

As of September 30, 2025, the Company was deemed to be the owner, for accounting purposes, of $18.8 million of long-lead equipment to be utilized for future manufacturing at a contract manufacturing organization, or CMO, facility.

Depreciation expense for the three and nine months ended September 30, 2025 was $0.5 million and $1.5 million, respectively. Depreciation expense for the three and nine months ended September 30, 2024 was $0.4 million and $1.2 million, respectively.

6. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following:


	September 30,		December 31,
(in thousands)	2025		2024
Payroll and benefits	$	13,178	$	13,095
Consulting services		1,115		1,608
Legal services		709		742
Research and development		26,918		15,401
Interest		829		—
Total	$	42,749	$	30,846

7. Long-Term Debt

On June 27, 2025 (the “Closing Date”), the Company entered into the Loan Agreement with Hercules, in its capacity as administrative agent and collateral agent (the “Agent”) and as a lender, and certain other financial institutions that from time to time become parties to the Loan Agreement as lenders (collectively, the “Lenders”). The Loan Agreement provides for term loans in an aggregate principal amount of up to $275.0 million under multiple tranches (the “Term Loans”), available as follows: (i) an initial term loan tranche funded on the Closing Date in aggregate principal amount of $100.0 million (the “Initial Tranche”); (ii) subject to the achievement of specified clinical, regulatory and commercial milestones, three additional term loan tranches totaling up to $115.0 million; and (iii) subject to approval by the Lenders’ investment committee in their discretion, a final term loan tranche of up to $60.0 million.

All unpaid principal and accrued and unpaid interest with respect to the Term Loans is due and payable in full on July 1, 2030 (the “Maturity Date”). The outstanding principal balance of the Term Loans bears interest at a floating interest rate per annum equal to the Wall Street Journal prime rate, subject to a floor of 7.50%, plus 2.45%. Accrued interest on the outstanding Term Loans is payable monthly. The Company may make payments of interest only until July 1, 2028, which interest only period may be extended until the Maturity Date upon the achievement of specified clinical, regulatory and commercial milestones. At the end of the interest only period, the Company is required to begin repayment of the outstanding principal of the Term Loans in equal monthly installments (or, in a single installment, if the interest-only period has been extended to the Maturity Date).

As collateral for the obligations under the Loan Agreement, the Company has granted to the Agent, for the benefit of the Lenders, a first-priority security interest in substantially all of its property, inclusive of intellectual property, subject to customary permitted liens and other exceptions set forth in the Loan Agreement.

The Loan Agreement contains customary representations and warranties, events of default and affirmative and negative

covenants, including a minimum cash covenant (the “Minimum Cash Covenant”) requiring the Company to maintain specified levels of cash in accounts subject to a control agreement in favor of the Agent (“Qualified Cash”) during the period commencing on April 1, 2026 (or January 1, 2027 if the Company has raised at least $350.0 million of cumulative net cash proceeds between June 4, 2025 and December 15, 2026 from the issuance of equity or indebtedness or payments under certain royalty or license transactions). The Minimum Cash Covenant will initially be set at 60% of the then outstanding principal balance of the Term Loans, is subject to adjustment and will not be tested at any time when the Company’s market capitalization is greater than $1.65 billion. The Company is also required to maintain minimum net product revenue from the sale of z-basivarsen (also known as DYNE-101) and z-rostudirsen (also known as DYNE-251) starting nine months after U.S. Food and Drug Administration approval of z-basivarsen or z-rostudirsen (the “Minimum Revenue Covenant”) if the outstanding principal balance of the Term Loans exceed $100.0 million. The Minimum Revenue Covenant will not be tested for any month to the extent that for each day during such month either (i) Qualified Cash is at least 100% of the Company’s outstanding obligations under the Loan Agreement or (ii) the Company’s market capitalization is greater than $1.65 billion and Qualified Cash is at least 50% of the Company’s outstanding obligations under the Loan Agreement. Certain negative covenants under the Loan Agreement limit the ability of the Company, among other things, to incur future debt, grant liens, make investments, make acquisitions, distribute dividends and sell assets, subject in each case to certain exceptions.

Upon the occurrence of an event of default, including the failure by the Company to comply with the covenants under the Loan Agreement or the occurrence of a material adverse effect on the business, operations, properties, assets or financial condition of the Company, in each case subject to certain exceptions, and subject to any specified cure periods, all amounts owed by the Company under the Loan Agreement may be declared immediately due and payable by the Agent, and the Agent may foreclose on collateral.

The Loan Agreement requires the Company to pay closing fees, prepayment penalties and an end-of-term charge equal to 5.5% of the amount of Term Loans borrowed, which amount is due at the earlier of prepayment or the Maturity Date. A prepayment penalty applies to any prepayment of the Term Loans prior to the Maturity Date equal to (i) 2.0% of the principal amount prepaid if the prepayment occurs on or prior to the first anniversary of the Closing Date, (ii) 1.5% of the principal amount prepaid if the prepayment occurs after the first anniversary and on or prior to the second anniversary of the Closing Date, and (iii) 0.75% of the principal amount prepaid if the prepayment occurs after the second anniversary through the day before the Maturity Date.

The Company recorded debt discount and debt issuance costs of $1.2 million upon closing of the Loan Agreement. The Company is accruing the end-of-term charge on its condensed consolidated balance sheet.

Unamortized debt discount and issuance costs were recorded as a reduction of the carrying amount on the Term Loans and are amortized as interest expense using the effective-interest method. In addition, debt issuance costs of $0.5 million were recorded in restricted cash and other assets as of September 30, 2025.

As of September 30, 2025, the carrying value of the Term Loans approximates its fair value.

The obligations under the Term Loans as of September 30, 2025 consisted of the following (in thousands):


	September 30,
	2025
Principal term loan balance	$	100,000
Unamortized debt discount and issuance costs		(1,136	)
Accrued end of term fee		283
Long-term debt, net	$	99,147

The annual principal payments due under the Term Loans as of September 30, 2025 were as follows:


Year ending December 31,	(in thousands)
2025	$	—
2026		—
2027		—
2028		22,075
2029		47,650
2030		30,275
Total	$	100,000

The table of future principal payments excludes the end-of-term charge of 5.5% of the principal amount of the Term Loans borrowed, which is due upon the maturity of the Term Loans.

8. Stockholders' Equity

Common Stock

In November 2021, the Company filed a universal shelf registration statement on Form S-3 (the "2021 Shelf Registration Statement"), to register for sale from time to time up to $400.0 million of common stock, preferred stock, debt securities, warrants and/or units in one or more offerings. Further, in November 2021, the Company entered into an Open Market Sale Agreement (the "Sales Agreement") with Jefferies LLC ("Jefferies") as the Company's sales agent, and included in the 2021 Shelf Registration Statement a prospectus relating to the Sales Agreement pursuant to which, from time to time, the Company could offer and sell shares of its common stock having an aggregate offering price of up to $150.0 million in an "at-the-market" offering program. On January 4, 2024, the Company notified Jefferies that it was suspending and terminating the prospectus filed under the 2021 Shelf Registration Statement relating to the Sales Agreement for the Company's "at-the-market" offering program.

On March 5, 2024, the Company filed a universal shelf registration statement on Form S-3, (the “2024 Shelf Registration Statement”), and included a prospectus relating to the Sales Agreement. Under the 2024 Shelf Registration Statement, the Company may offer and sell debt securities, common stock, preferred stock, units and/or warrants from time to time at an indeterminate aggregate offering price in one or more offerings. In November 2024, the Company filed a prospectus supplement relating to the Sales Agreement, pursuant to which, in accordance with the Sales Agreement, the Company may offer and sell shares of its common stock having an aggregate offering price of up to $300.0 million in an “at-the-market” offering.

During the nine months ended September 30, 2025, the Company issued and sold an aggregate of 10,660,159 shares of common stock pursuant to the Sales Agreement for aggregate net proceeds of $140.6 million, after deducting commissions and offering expenses payable by the Company. The Company sold such shares at a weighted average price of $13.60 per share.

Atlas Venture and related affiliated entities were beneficial owners of approximately 6.4% of the Company's outstanding common stock as of September 30, 2025. The chairman of the Company's board of directors is a partner at Atlas Venture. On January 27, 2025, the Company issued and sold 1,111,111 shares of common stock through its at-the-market offering program that Atlas Venture and related affiliated entities purchased at a purchase price of $13.50 per share for aggregate gross proceeds of $15.0 million. The shares were purchased at the prevailing market price.

In July 2025, the Company completed a follow-on public offering, pursuant to which the Company issued and sold 27,878,788 shares of the Company's common stock. The Company received net proceeds of $215.8 million, after deducting underwriting discounts and commissions and offering expenses paid by the Company.

2020 Stock Incentive Plan

In August 2020, the Company’s board of directors adopted and the Company’s stockholders approved the 2020 Stock Incentive Plan, (the "2020 Plan"), which became effective on September 16, 2020. The 2020 Plan provides for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock units ("RSUs") and other stock-based awards to employees, directors, consultants and advisors of the Company. The 2020 Plan is administered by the Company’s board of directors or by a committee appointed by the board of directors. Upon the effectiveness of the 2020 Plan, the Company ceased granting awards under the 2018 Stock Incentive Plan. The number of shares initially reserved for issuance under the 2020 Plan was 4,884,233. The number of shares of common stock reserved for issuance under the 2020 Plan may automatically increase on the first day of each fiscal year, beginning

with the fiscal year commencing on January 1, 2021 and continuing for each fiscal year until, and including the fiscal year commencing on, January 1, 2030, in an amount equal to the lower of (1) 5% of the shares of common stock outstanding on such date and (2) an amount determined by the Company’s board of directors. On January 1, 2025, 5,115,931 shares were added to the shares reserved for issuance under the 2020 Plan in the fifth of these annual increases.

As of September 30, 2025, 6,009,631 shares remained available for future issuance under the 2020 Plan.

2020 Employee Stock Purchase Plan

In August 2020, the Company’s board of directors adopted and the Company’s stockholders approved the 2020 Employee Stock Purchase Plan (the “2020 ESPP”), which became effective September 16, 2020. The 2020 ESPP is administered by the Company’s board of directors or by a committee appointed by the board of directors. The 2020 ESPP initially provides participating employees with the opportunity to purchase up to an aggregate of 488,414 shares of common stock. The number of shares of common stock reserved for issuance under the 2020 ESPP may automatically increase on the first day of each fiscal year, beginning with the fiscal year commencing on January 1, 2021 and continuing for each fiscal year until, and including the fiscal year commencing on, January 1, 2030, in an amount equal to the least of (1) 1,953,656 shares of common stock, (2) 1% of the shares of common stock outstanding on such date, and (3) an amount determined by the board of directors.

As of September 30, 2025, no offering periods have commenced under the 2020 ESPP and 488,414 shares remained available for issuance.

2024 Inducement Stock Incentive Plan

In March 2024, the Company's board of directors adopted the 2024 Inducement Stock Incentive Plan (the "2024 Inducement Plan"). The 2024 Inducement Plan provides for the grant of nonstatutory stock options, stock appreciation rights, restricted stock, RSUs and other stock-based awards with respect to an aggregate of 900,000 shares of Common Stock (subject to adjustment as provided in the 2024 Inducement Plan). Awards under the 2024 Inducement Plan may only be granted to new employees who were not previously an employee or director of the Company or are commencing employment with the Company following a bona fide period of non-employment, in either case, as an inducement material to the individual’s entering into employment with the Company and in accordance with the requirements of Nasdaq Stock Market Rule 5635(c)(4). In February 2025, the Company's board of directors approved an additional 1,000,000 shares for issuance under the 2024 Inducement Plan. In April 2025, the Company granted inducement equity awards to three new employees as a material inducement to acceptance of their respective employment consisting of stock options to purchase up to an aggregate of 330,200 shares of the Company’s common stock and RSUs with respect to an aggregate of 101,900 shares of the Company’s common stock. During the three months ended September 30, 2025, the Company did not grant any inducement equity awards under the 2024 Inducement Plan.

As of September 30, 2025, 440,447 shares remained available for future issuance under the 2024 Inducement Plan.

Stock option valuation

The fair value of stock option grants is estimated using the Black-Scholes option-pricing model. The fair value is determined based upon the quoted price of the Company’s common stock. The Company lacks company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. For options with service-based vesting conditions, the expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected

dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

The assumptions that the Company used to determine the grant-date fair value of options granted were as follows:


	Nine Months Ended September 30,
	2025		2024
Expected volatility	67%		66%
Risk-free interest rate	3.71% — 4.52%		3.46% — 4.65%
Expected term (in years)	6		6
Expected dividend yield		—		—

Stock option activity

A summary of the Company’s stock option activity and related information for the nine months ended September 30, 2025 is as follows:


(in thousands, except share and per share data)	Options			Weighted Average Exercise Price		Weighted Average Remaining Life (in years)		Aggregate Intrinsic Value
Outstanding as of January 1, 2025		8,681,473		$	19.47		7.3	$	61,021
Granted		3,149,353			10.44
Exercised		(729,784	)		6.35
Canceled		(1,451,640	)		18.71
Outstanding as of September 30, 2025		9,649,402		$	17.86		8.2	$	14,497
Options exercisable as of September 30, 2025		3,528,987		$	17.11		6.7	$	6,051
Options vested or expected to vest as of September 30, 2025		9,649,402		$	17.86		8.2	$	14,497

The intrinsic value of options exercised for the nine months ended September 30, 2025 and 2024 totaled $4.3 million and $83.3 million, respectively. The weighted-average grant date fair value of the options granted during the nine months ended September 30, 2025 and 2024 was $6.78 per share and $19.65 per share, respectively. As of September 30, 2025 there was $66.0 million of unrecognized compensation expense, which the Company expects to recognize over a weighted-average period of 2.9 years.

Effective January 2025, the Company entered into a consulting agreement with its former chief medical officer resulting in the modification of previously issued stock option awards. The modification resulted in $0.9 million of additional stock-based compensation expense, all of which was recognized during the three months ended March 31, 2025. The expense was recorded within research and development expenses on the condensed consolidated statements of operations and comprehensive loss. Based on the terms of the consulting agreement, options to purchase 58,659 shares of common stock were forfeited in January 2025.

Effective April 2025, the Company entered into a consulting agreement with its former senior vice president of finance and administration resulting in the modification of previously issued stock option awards. The modification resulted in $0.1 million of additional stock-based compensation expense, all of which was recognized during the three months ended June 30, 2025. The expense was recorded within general and administrative expenses on the condensed consolidated statements of operations and comprehensive loss. Based on the terms of the consulting agreement, options to purchase 88,508 shares of common stock were forfeited in April 2025.

In July 2025, the Company granted 591,685 stock options, vesting over a three-year term from the grant date and contingent upon the achievement of certain market conditions. The fair value of these market-based stock options was estimated using a Monte Carlo valuation method, incorporating various option pricing inputs. Ultimately, over the three-year vesting term, these market-based stock options will result in an additional stock-based compensation expense of $2.9 million, with $0.3 million recognized during the quarterly period ended September 30, 2025.

Restricted stock units

An RSU represents the right to receive one share of common stock upon vesting of the RSU. The Company grants RSUs with service conditions that vest in four equal annual installments provided that the employee remains employed with the Company, RSUs with service conditions that vest in sixteen equal quarterly installments provided that the employee

remains employed with the Company and RSUs with performance-based vesting conditions. As of September 30, 2025, there are no RSUs with performance-based vesting conditions outstanding. The fair value of each RSU is based on the closing price of the Company’s common stock on the date of grant. A summary of the Company’s RSU activity and related information for the nine months ended September 30, 2025 is as follows:


	Number of Shares Underlying RSUs			Weighted Average Grant Date Fair Value
Issued and unvested as of January 1, 2025		3,722,024		$	20.49
Granted		603,600			10.86
Vested		(1,025,888	)		17.50
Forfeited		(708,399	)		17.12
Issued and unvested as of September 30, 2025		2,591,337		$	20.35

The fair value of RSUs vested during the nine months ended September 30, 2025 and 2024 totaled $12.8 million and $27.1 million, respectively. The weighted average grant date fair value of RSUs granted during the nine months ended September 30, 2024 was $34.32 per share. As of September 30, 2025, there was $48.3 million of unrecognized compensation costs related to unvested RSUs, which are expected to be recognized over a weighted-average period of 2.8 years.

Effective January 2025, the Company entered into a consulting agreement with its former chief medical officer resulting in the modification of previously issued RSU awards. The modification resulted in the recognition of $0.3 million of additional stock-based compensation expense, all of which was recognized during the three months ended March 31, 2025. The expense was recorded within research and development expenses on the condensed consolidated statements of operations and comprehensive loss. Based on the terms of the consulting agreement, 76,662 RSUs were forfeited in January 2025.

Effective April 2025, the Company entered into a consulting agreement with its former senior vice president of finance and administration resulting in the modification of previously issued RSU awards. The modification resulted in the recognition of $0.2 million of additional stock-based compensation expense, all of which was recognized during the three months ended June 30, 2025. The expense was recorded within general and administrative expenses on the condensed consolidated statements of operations and comprehensive loss. Based on the terms of the consulting agreement, 65,350 RSUs were forfeited in April 2025.

The Company recorded stock-based compensation expense in the following expense categories of its condensed consolidated statements of operations and comprehensive loss:


	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands)	2025		2024		2025		2024
Research and development	$	6,258	$	4,450	$	20,095	$	12,252
General and administrative		4,824		4,295		14,530		23,135
Total	$	11,082	$	8,745	$	34,625	$	35,387

9. Segment Reporting

The Company’s segment determination is based on the financial results that are regularly evaluated by the Company’s chief operating decision maker ("CODM") to determine resource allocation and assess performance. The Company's CODM is its chief executive officer. The Company has one operating and one reportable segment. Net long-lived assets are all physically located in the United States and the total assets of the segment equal the total assets presented on the condensed consolidated balance sheet. The primary financial measure by which the CODM evaluates the business is net loss. The CODM uses net loss to monitor budget versus actual results to assess performance of the segment. A summary of the significant segment expenses reported to the CODM are shown below for the three and nine months ended September 30, 2025 and 2024:


	Three Months Ended September 30,						Nine Months Ended September 30,
(in thousands)	2025			2024			2025			2024
Operating Expenses
Z-basivarsen (DM1)	$	37,853		$	30,922		$	117,964		$	53,047
Z-rostudirsen (DMD)		22,666			29,021			73,314			62,677
Platform and external research and development		5,769			10,439			21,399			20,622
Personnel related		22,517			15,620			62,730			44,986
Stock-based compensation		11,082			8,745			34,625			35,387
Facility-related and other		9,448			5,988			26,703			17,345
Professional and consulting fees		4,557			4,924			15,320			12,714
Interest income		(8,476	)		(9,276	)		(22,202	)		(19,330	)
Interest expense		2,904			—			2,998			—
Other expense (income), net		(279

Large accelerated filer

Accelerated filer

Non-accelerated filer

Smaller reporting company

Emerging growth company

Dyne Therapeutics, Inc. 10-Q