Share-based compensation

3 Months Ended

Mar. 31, 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 March 31, 2025, there were 4,475,485 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 March 31, 2025.

2024 Inducement Plan

In October 2024, the Company adopted the 2024 Inducement Plan, or the 2024 Plan, to reserve 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. The terms and conditions of the 2024 Plan are substantially similar to the Company’s 2020 Plan. As of March 31, 2025, there were 414,300 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 664,608 shares. As of March 31, 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 March 31, 2025.

Stock options

A summary of option activity under the Plans during the three months ended March 31, 2025 is as follows:

				Weighted
		Weighted		average	Aggregate
		average		remaining	Intrinsic
	Number of	exercise price		contractual	Value
	shares	per share		term (years)	(in thousands)
Outstanding at December 31, 2024	11,990,781	$	10.02	8.69	$	34,209
Granted	224,000		10.10
Exercised	(256,055)		1.52
Forfeited	(348,748)		6.13
Expired	(111,130)		20.27
Outstanding at March 31, 2025	11,498,848	$	10.21	8.64	$	12,063
Exercisable at March 31, 2025	3,563,637	$	6.26	7.60	$	10,228

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 three months ended March 31, 2025 and 2024 was $7.76 and $14.62 per share, respectively. The aggregate intrinsic value of options exercised during the three months ended March 31, 2025 and 2024 was $2.1 million and $2.5 million, respectively.

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

	Three Months Ended March 31,
	2025			2024
Expected volatility		90.4	%		84.1	%
Risk-free interest rate		4.3	%		4.1	%
Expected term (in years)		6.08			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 March 31,
	2025		2024
Research and development	$	2,434	$	383
General and administrative		3,269		1,776
Total share-based compensation expense	$	5,703	$	2,159

Unrecognized share-based compensation related to stock options was $68.2 million as of March 31, 2025 and is expected to be recognized over a weighted average period of 3.1 years.