12. 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 six months ended June 30, 2025, 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 June 30, 2025, BVF owned approximately 21.5% of the Company’s total outstanding shares of common stock, and if all the shares of Series X Preferred Stock were converted (without taking into account beneficial ownership limitations), BVF would own 44.5% 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 June 30, 2025, 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.

2018 Common Stock ATM Agreement

On December 18, 2018, the Company entered into the 2018 Common Stock ATM Agreement with HCW, under which the Company may offer and sell from time to time at its sole discretion shares of its common stock through HCW as its sales agent, in an aggregate amount not to exceed $30.0 million. HCW 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 HCW a commission of up to 3% of the gross proceeds of any shares of common stock sold under the 2018 Common Stock ATM Agreement. On March 10, 2021, the Company amended the 2018 Common Stock ATM Agreement with HCW to increase the aggregate amount of shares of its common stock that it could sell through HCW as its sales agent to $50.0 million. No shares have been sold under the 2018 Common Stock ATM Agreement since the agreement was executed.

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2021 Series B Preferred Stock ATM Agreement

On August 5, 2021, the Company entered into the 2021 Series B Preferred Stock ATM Agreement with B. Riley, under which the Company may offer and sell from time to time, at its sole discretion, through or to B. Riley, as agent or principal an aggregate amount not to exceed $50.0 million of its Series B Depositary Shares. B. Riley 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 B. Riley a commission of up to 3% of the gross proceeds of any Series B Depositary Shares sold under the 2021 Series B Preferred Stock ATM Agreement. No shares have been sold under the 2021 Series B Preferred Stock ATM Agreement since the agreement was executed.

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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. During the six months ended June 30, 2025, the Company purchased a total of 107,510 shares of its common stock for $2.4 million. During the three months ended June 30, 2025, the Company repurchased and retired shares of its common stock with an aggregate fair market value of approximately $1.8 million under its stock repurchase program. 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 exceeded this threshold during the second quarter, the Company recorded an excise tax liability of $24,000, which is reflected as a reduction to stockholders’ equity in the condensed consolidated balance sheet as of June 30, 2025. From the inception of the stock repurchase program through June 30, 2025, the Company purchased a total of 108,170 shares of its common stock pursuant to the stock repurchase program for $2.4 million.