Share-based compensation

9 Months Ended

Sep. 30, 2025

Share-based compensation

Share-based compensation

10. Share-based compensation

2020 Equity Incentive Plan

In September 2020, the Company adopted the 2020 Equity Incentive Plan, or the 2020 Plan, which supersedes all prior equity incentive plans. On January 1, 2025, the number of shares available for future issuance under the 2020 Plan increased by 2,578,433 shares. As of September 30, 2025, there were 639,588 shares available for issuance under the 2020 Plan.

In October 2023, the Company completed its merger with Morphimmune, Inc. and assumed the Morphimmune 2020 Equity Incentive Plan, or the Morphimmune Plan. There were 555,895 shares available for issuance under the Morphimmune Plan as of September 30, 2025.

2024 Inducement Plan

In October 2024, the Company adopted the 2024 Inducement Plan, or the 2024 Plan, and reserved 2,000,000 shares of the Company’s common stock to be used exclusively for grants of equity awards to individuals that were not previously employees or directors of the Company, as an inducement material to the individual’s entry into employment with the Company. In May 2025, the Compensation Committee of the Board of Directors of the Company approved an amendment to the 2024 Plan increasing the aggregate shares reserved under the 2024 Plan from 2,000,000 to 3,500,000. The terms and conditions of the 2024 Plan are substantially similar to the Company’s 2020 Plan. As of September 30, 2025, there were 1,427,300 shares available for issuance under the 2024 Plan.

Stock options granted for Chief Executive Officer

On June 28, 2023, Clay Siegall was granted 2,137,080 options to purchase shares of the Company’s common stock at an initial exercise price of $5.91 per share, or the Inducement Grant. The options vest over time during Dr. Siegall’s continued employment with the Company, which commenced on October 2, 2023. 25% of the options granted vest after one year of employment with the Company, and the remaining 75% vest monthly over the 36 months immediately following the one-year anniversary.

The Inducement Grant, the Morphimmune Plan, the 2024 Plan and the 2020 Plan are collectively referred to as the Plans.

2020 Employee Stock Purchase Plan

The Company adopted the 2020 Employee Stock Purchase Plan, or ESPP, in September 2020. On January 1, 2025, the shares of common stock authorized for issuance under the ESPP increased by 644,608 shares. As of September 30, 2025, there were 1,550,859 shares available for issuance under the ESPP. No shares of common stock have been issued under the ESPP as of September 30, 2025.

Stock options

A summary of option activity under the Plans during the nine months ended September 30, 2025 is as follows:

	Number of shares			Weighted average exercise price per share		Weighted average remaining contractual term (years)		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2024		11,990,781		$	10.02		8.69	$	34,209
Granted		5,386,784			10.19
Exercised		(381,992	)		2.66
Forfeited		(1,062,581	)		9.42
Expired		(237,184	)		22.94
Outstanding at September 30, 2025		15,695,808		$	10.09	8.73		$	41,765
Exercisable at September 30, 2025		4,972,974		$	7.69	7.83		$	25,837

Aggregate intrinsic value in the above table is calculated as the difference between the exercise price of the options and the Company’s fair value of its common stock as of period end.

The weighted-average grant date fair value of stock options granted during the nine months ended September 30, 2025 and 2024 was $7.53 and $11.47 per share, respectively. The aggregate intrinsic value of options exercised during the nine months ended September 30, 2025 and 2024 was $2.5 million and $8.1 million, respectively.

The weighted average assumptions used in the Black-Scholes option-pricing model for stock options granted were:

	Nine Months Ended September 30,
	2025			2024
Expected volatility		85.1	%		89.8	%
Risk-free interest rate		4.0	%		4.0	%
Expected term (in years)	6.06				6.06
Expected dividend yield		—	%		—	%

Share-based compensation expense recorded in the condensed consolidated statements of operations and comprehensive loss is as follows (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Research and development	$	2,851	$	1,820	$	7,518	$	3,244
General and administrative		3,896		3,072		10,279		7,034
Total share-based compensation expense	$	6,747	$	4,892	$	17,797	$	10,278

Unrecognized share-based compensation related to stock options was $87.4 million as of September 30, 2025 and is expected to be recognized over a weighted average period of 3.1 years.