13. Capital Stock

Series X Convertible Preferred Stock

Classification— The Company evaluated the convertible preferred stock for liability or equity classification under the applicable accounting guidance and determined that equity treatment was appropriate. Specifically, the shares of Series X Convertible Preferred Stock are not mandatorily redeemable and do not embody an unconditional obligation to deliver a variable number of shares. The Company determined that the convertible preferred stock would be recorded as temporary equity, given that they are redeemable for cash or other assets upon the occurrence of certain event that is not solely within control of the Company. The Company has also evaluated the embedded conversion and contingent redemption features within the Series X Convertible Preferred Stock in accordance with the accounting guidance for derivatives and determined that bifurcation is not required for any embedded feature.

Dividends

During the three months ended March 31, 2026, the Board declared and paid cash dividends on the Company’s Series A Preferred Stock and Series B Depositary shares as follows:

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BVF Ownership

As of March 31, 2026, BVF owned approximately 21.7% of the Company’s total outstanding shares of common stock, and if all the shares of Series X Convertible Preferred Stock were converted (without taking into account beneficial ownership limitations), BVF would own 44.9% of the Company’s total outstanding shares of common stock. The Company’s Series A Preferred Stock becomes convertible upon the occurrence of specific events and as of March 31, 2026, the contingency was not met, therefore the Series A Preferred Stock owned by BVF is not included in the as-converted ownership calculation. Due to its significant equity ownership, BVF is considered a related party of the Company.

2025 Common Stock ATM Agreement

On October 3, 2025, the Company entered into the 2025 Common Stock ATM Agreement with Leerink, under which the Company may offer and sell from time to time at its sole discretion shares of its common stock through Leerink as its sales agent, in an aggregate amount not to exceed $75.0 million. The 2025 Common Stock ATM Agreement replaced the 2018 Common Stock ATM Agreement that was terminated in September 2025. Leerink may sell the shares by any method permitted by law deemed to be an “at the market” offering as defined in Rule 415 of the Securities Act and will use its commercially reasonable efforts consistent with its normal trading and sales practices to sell the shares up to the amount specified. The Company will pay Leerink a commission of up to 3% of the gross proceeds of any shares of common stock sold under the 2025 Common Stock ATM Agreement. During the three months ended March 31, 2026, the Company did not sell any shares of its common stock under the 2025 Common Stock ATM Agreement.

2025 Series B Preferred Stock ATM Agreement

On October 3, 2025, the Company entered into the 2025 Series B Preferred Stock ATM Agreement with HCW, under which the Company may offer and sell from time to time at its sole discretion depositary shares, each representing 1/1000th of a share of the Company’s Series B Preferred Stock, through HCW as its sales agent, in an aggregate amount not to exceed $50.0 million. The 2025 Series B Preferred Stock ATM Agreement replaced the 2021 Series B Preferred Stock ATM Agreement that was terminated in September 2025. HCW may sell the depositary shares by any method permitted by law deemed to be an “at the market” offering as defined in Rule 415 of the Securities Act and will use its commercially reasonable efforts consistent with its normal trading and sales practices to sell the depositary shares up to the amount specified. The Company will pay HCW a commission of up to 3% of the gross proceeds of any depositary shares sold under the 2025 Series B Preferred Stock ATM Agreement. During the three months ended March 31, 2026, the Company did not sell any shares of its Series B Preferred Stock under the 2025 Series B Preferred Stock ATM Agreement.

Stock Repurchase Program

On January 2, 2024, the Board authorized the Company’s stock repurchase program, which permits the Company to purchase up to $50.0 million of its common stock through January 2027. Under the program, the Company has discretion in determining the conditions under which shares may be purchased from time to time, including through transactions in the open market, in privately negotiated transactions, under plans compliant with Rule 10b5-1 under the Exchange Act, or by other means in accordance with applicable laws. The manner, number, price, structure, and timing of the repurchases, if any, will be determined at the Company’s sole discretion and repurchases, if any, depend on a variety of factors, including legal requirements, price and economic and market conditions, royalty and milestone acquisition opportunities, and other factors. The repurchase authorization does not obligate the Company to acquire any particular amount of its common stock. The Board may suspend, modify, or terminate the stock repurchase program at any time without prior notice.

On December 3, 2025, the Company entered into a stock purchase agreement with a stockholder to repurchase 539,131 shares of its common stock, originally issued in 2017, for $13.6 million in cash. The transaction was consummated on December 4, 2025, and the repurchased shares were cancelled.

During the three months ended March 31, 2026, the Company purchased a total of 10,902 shares of its common stock for $0.3 million. Pursuant to Section 4501 of the Internal Revenue Code, a 1% excise tax is imposed on the aggregate

fair market value of stock repurchases during the taxable year, provided the total value of repurchases exceeds a $1.0 million de minimis threshold. As cumulative repurchases did not exceed this threshold during the three months ended March 31, 2026, the Company recorded no excise tax liability as of March 31, 2026. From the inception of the stock repurchase program through March 31, 2026, the Company purchased a total of 659,610 shares of its common stock pursuant to the stock repurchase program for $16.3 million.