Long-Term Debt

12 Months Ended

Dec. 31, 2025

The Company’s long-term debt consisted of the following (in thousands):


	December 31,
	2025		2024
5.00% 2027 Convertible Notes	$	26,485	$	175,250
4.625% 2031 Convertible Notes	225,000		—
Unamortized debt issuance costs	(7,272)		(5,566)
Total convertible notes payable	$	244,213	$	169,684

As of December 31, 2025 and December 31, 2024, the effective interest rate of the Convertible Senior Notes due 2027 is 6.2%. As of December 31, 2025, the effective interest rate of the Convertible Senior Notes due 2031 is 5.3%.

The interest expense incurred in connection with the convertible notes payable consisted of the following (in thousands):


	Year Ended December 31,
	2025		2024		2023
Coupon interest	$	9,867	$	8,762	$	9,779
Amortization of debt issuance costs	1,660		1,668		1,689
Total interest expense on convertible notes payable	$	11,527	$	10,430	$	11,468

2031 Convertible Notes

In August 2025, the Company issued $225.0 million aggregate principal amount of its 4.625% Convertible Senior Notes due 2031 (the “2031 Notes”) consisting of (a) $175.3 million principal amount of 2031 Notes issued in exchange for $148.8 million principal amount of the Company’s 5.00% Convertible Senior Notes due 2027 (the “2027 Notes”), and (b) approximately $49.7 million principal amount of 2031 Notes issued for cash, in each case, pursuant to exemptions from registration under the Securities Act of 1933, as amended (the “Securities Act”), and the rules and regulations thereunder.

The 2031 Notes were issued pursuant to, and are governed by, an indenture (the “2031 Indenture”), dated as of August 27, 2025, between the Company and The Bank of New York Mellon Trust Company, N.A. as trustee.

The 2031 Notes are senior, unsecured obligations of the Company and accrue interest at a rate of 4.625% per annum, payable semi-annually in arrears on March 1 and September 1 of each year, beginning on March 1, 2026. The 2031 Notes will mature on September 1, 2031, unless earlier repurchased, redeemed or converted. Before June 1, 2031, noteholders have the right to convert their 2031 Notes only upon the occurrence of certain events. From and including June 1, 2031, noteholders may convert their 2031 Notes at any time at their election until the close of business on the second scheduled trading day immediately before the maturity date. The Company will settle conversions by paying cash, shares of its common stock or a combination of cash and shares of its common stock, at its election, based on the applicable conversion rate. The initial conversion rate is 89.7384 shares of common stock per $1,000 principal amount of 2031 Notes, which represents an initial conversion price of approximately $11.14 per share of common stock. The initial conversion price represents a premium of approximately 28% over the last reported sale price of the Company’s common stock on August 20, 2025. The conversion rate and conversion price will be subject to customary adjustments upon the occurrence of certain events. In addition, if certain corporate events that constitute a “Make-Whole Fundamental Change” (as defined in the 2031 Indenture) occur, then the conversion rate will, in certain circumstances, be increased for a specified period of time. The initial maximum conversion rate is 114.4164 shares of common stock per $1,000 principal amount of 2031 Notes.

The 2031 Notes are redeemable, in whole or in part (subject to certain limitations), for cash at the Company’s option at any time, and from time to time, on or after September 5, 2028 and before the 41st scheduled trading day immediately before the maturity date, but only if the last reported sale price per share of the Company’s common stock exceeds 130% of the conversion price for a specified period of time. However, the Company may not redeem less than all of the outstanding 2031 Notes unless at least $50.0 million aggregate principal amount of 2031 Notes are outstanding and not called for redemption as of the time the Company sends the related redemption notice. The redemption price is equal to the principal amount of the 2031 Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the relevant redemption date.

Holders of the 2031 Notes will have the right to require the Company to repurchase all or part of their 2031 Notes for cash in the event of certain Fundamental Changes (as defined in the 2031 Indenture), at a repurchase price equal to 100% of the principal amount of the 2031 Notes to be repurchased, plus accrued and unpaid interest, if any, to, but excluding, the relevant repurchase date.

In accordance with ASC 470-50 Modification and Extinguishments, the Company determined that the modified terms of the $175.3 million principal amount of the 2031 Notes were substantially different than the terms of $148.8 million principal amount of the 2027 Notes they were exchanged for, and therefore, the exchange was accounted for as an extinguishment of the 2027 Notes and Issuance of 2031 Notes. The Company recorded a loss on debt extinguishment of $28.7 million related to the exchange.

The initial purchasers’ fees and the Company’s issuance costs related to the issuance of the 2031 Notes totaled $7.1 million, which were recorded as a reduction to the 2031 Notes on the consolidated balance sheet and is being amortized and recognized as additional interest expense over the six-year contractual term of the 2031 Notes using the effective interest rate of 5.3%

2027 Convertible Notes

In December 2022, the Company issued $175.3 million aggregate principal amount of 5.0% Convertible Senior Notes that will mature on December 15, 2027 (the “2027 Notes”), unless earlier converted, redeemed, or repurchased. In August 2025, the Company exchanged $175.3 million aggregate principal amount of newly issued 2031 Notes for $148.8 million aggregate principal amount of 2027 Notes, as discussed above, after which $26.5 million aggregate principal amount of 2027 Notes remained outstanding. The 2027 Notes were issued in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended, and pursuant to an indenture dated December 20, 2022 (the “2027 Indenture”) between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee. Concurrently with the

issuance of the 2027 Notes, the Company completed a public offering of shares of its common stock. The Company received $166.4 million in net proceeds from the issuance of the 2027 Notes after deducting the initial purchasers’ fees and the Company’s offering expenses. The 2027 Notes bear cash interest at a rate of 5.0% per year, payable semiannually in arrears on June 15 and December 15 of each year, beginning on June 15, 2023.

The 2027 Notes are convertible at the option of the holders at any time prior to the close of business on the business day immediately preceding September 15, 2027, only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on March 31, 2023 (and only during such calendar quarter), if the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price for the 2027 Notes on each applicable trading day; (2) during the five business day period after any ten consecutive trading day period (the “measurement period”) in which the trading price (as defined in the 2027 Indenture) per $1,000 principal amount of the 2027 Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate for the 2027 Notes on each such trading day; (3) if the Company calls such 2027 Notes for redemption, at any time prior to the close of business on the scheduled trading day immediately preceding the redemption date, but only with respect to the 2027 Notes called (or deemed called) for redemption; and (4) upon the occurrence of specified corporate events as set forth in the 2027 Indenture. On or after September 15, 2027, until the close of business on the business day immediately preceding the maturity date (December 15, 2027), holders of the 2027 Notes may convert all or any portion of their 2027 Notes at any time, regardless of the foregoing conditions. Upon conversion, the Company may satisfy its conversion obligation by paying or delivering, as the case may be, cash, shares of the Company’s common stock, or a combination of cash and shares of the Company’s common stock, at the Company’s election, in the manner and subject to the terms and conditions provided in the 2027 Indenture.

The conversion rate for the 2027 Notes will initially be 80.0000 shares of the Company’s common stock per $1,000 principal amount of 2027 Notes, which is equivalent to an initial conversion price of $12.50 per share of common stock. The initial conversion price of the 2027 Notes represents a conversion premium of 25% of the public offering price in the Company’s concurrent common stock offering that closed on December 20, 2022. The conversion rate for the 2027 Notes is subject to adjustment under certain circumstances in accordance with the terms of the 2027 Indenture. In addition, following certain corporate events that occur prior to the maturity date of the 2027 Notes or if the Company delivers a notice of redemption in respect of the 2027 Notes, the Company will, under certain circumstances, increase the conversion rate of the 2027 Notes for a holder who elects to convert its 2027 Notes (or any portion thereof) in connection with such a corporate event or convert its 2027 Notes called (or deemed called) for redemption during the related redemption period (as defined in the 2027 Indenture), as the case may be.

The Company may not redeem the 2027 Notes prior to December 22, 2025. The Company may redeem for cash all or any portion of the 2027 Notes, at its option, on or after December 22, 2025, if the last reported sale price of the common stock has been at least 130% of the conversion price for the 2027 Notes then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period (including the last trading day of such period) ending on, and including, the trading day immediately preceding the date on which the Company provides notice of redemption at a redemption price equal to 100% of the principal amount of the 2027 Notes to be redeemed, plus accrued and unpaid interest, to, but excluding, the redemption date. If the Company redeems less than all the outstanding 2027 Notes, at least $50 million aggregate principal amount of 2027 Notes must be outstanding and not subject to redemption as of the date of the relevant notice of redemption. No sinking fund is provided for the 2027 Notes.

If the Company undergoes a Fundamental Change (as defined in the 2027 Indenture), holders may require, subject to certain conditions and exceptions as set forth in the 2027 Indenture, the Company to repurchase for cash all or any portion of their 2027 Notes at a Fundamental Change repurchase price equal to 100% of the principal amount of the 2027 Notes to be repurchased, plus accrued and unpaid interest, to, but excluding, the Fundamental Change repurchase date. If a holder of the 2027 Notes converted upon a Make-Whole Fundamental Change (as described in the 2027 Indenture), they may be eligible to receive a make-whole premium through an increase to the conversion rate up to a maximum of 20.0000 shares per $1,000 principal amount of 2027 Notes (subject to other adjustments as described in the 2027 Indenture).

In accounting for the issuance of the 2027 Notes, the Company determined that the scope exceptions provided under ASC Topic 815-40, Derivatives and Hedging – Contracts in Entity’s Own Equity (“ASC 815-40”) apply to all but one of the conversion features embedded in the 2027 Notes. This remaining conversion feature, which is associated with a Fundamental Change of the Company, was determined to have a de minimis value as of December 31, 2025, 2024, and 2023.

The initial purchasers’ fees and the Company’s issuance costs related to the 2027 Notes totaled $8.8 million, which were recorded as a reduction to the 2027 Notes on the consolidated balance sheet. The $8.8 million of debt issuance costs is being amortized and recognized as additional interest expense over the five-year contractual term of the 2027 Notes using an effective interest rate of 6.2%.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

NOVAVAX INC 10-K