In September 2023, the Company adopted the 2023 Equity Incentive Plan (2023 Plan). The 2023 Plan provides for the grant of stock options, restricted stock awards, restricted stock unit awards, and other stock-based awards to employees, directors, and non-employee service providers of the Company. The 2023 Plan replaced the Company’s 2020 Equity Incentive Plan (“2020 Plan” and together with the 2023 Plan, Plans). The Company no longer grants stock options or other awards under its 2020 Plan, but any stock options outstanding under the 2020 Plan remain outstanding and effective in accordance with their terms. Awards granted under the 2023 Plan expire no later than ten years from the date of grant. The price of stock options shall not be less than 100% of the estimated fair value on the date of grant and typically vest over a four-year period although may be granted with different vesting terms.

The 2023 Plan provides for an annual increase, to be added on the first day of each fiscal year, by up to 5% of the Company’s outstanding shares of common stock as of the last day of the prior year. On January 1, 2025, the number of shares of common stock available for issuance under the 2023 Plan increased by 8,085,495 shares as a result of the automatic increase provision of the 2023 Plan.

In September 2023, the Company adopted the 2023 Employee Share Purchase Plan (ESPP). The Company may hold one or more offering periods each year during which employees will be able to purchase shares under the ESPP through payroll deductions made over the term of the offering. The per-share purchase price at the end of each offering period is equal to the lesser of 85% of the closing price of the Company's common stock at the beginning or end of the offering period. On January 1, 2025, the number of shares of common stock available for issuance under the ESPP increased by 1,617,099 shares as a result of the automatic increase provision of the ESPP. No shares were issued under the ESPP during the year the three months ended March 31, 2025.

Stock Option Activity


	Outstanding Stock Options			Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
	(in thousands, except per share amounts and years)
Outstanding as of December 31, 2024		13,927		$	9.20		7.8	$	44,953
Granted		11,995			1.68
Exercised		—			—
Canceled and forfeited		(2,166	)		8.16
Expired		(121	)		3.58
Outstanding as of March 31, 2025		23,635		$	5.51		8.9	$	—
Exercisable as of March 31, 2025		6,490		$	7.54		7.6	$	—

The stock option activity table above excludes options to purchase 446,068 shares of common stock that were originally granted with market conditions to one of the Company’s executives.

The Company’s Plans allow for the grant of restricted common stock and restricted stock units to certain employees, executives, non-employee scientific advisors, and third-party service providers. The restrictions lapse over time primarily according to service-based vesting conditions of each award. In the event of a voluntary or involuntary termination of the holder’s continuous provision of services to the Company, any unvested portion of the restricted stock award is automatically forfeited.

The following table summarizes the Company’s restricted stock activity:


	Shares of Restricted Common Stock			Weighted- Average Grant Date Fair Value Per Share		Shares of Restricted Stock Units			Weighted- Average Grant Date Fair Value Per Share
	(in thousands, except per share amounts)
Outstanding and unvested as of December 31, 2024		371		$	10.82		1,441		$	17.32
Granted		—			—		—			—
Vested		(29	)		11.50		(269	)		18.07
Forfeited and expired		—			—		—			—
Cancelled		(231	)		8.87		(66	)		18.07
Outstanding and unvested as of March 31, 2025		111		$	14.67		1,106		$	17.08

The following table summarizes total stock-based compensation included in the Company’s condensed consolidated statements of operations and comprehensive loss:


	Three Months Ended March 31,
	2025		2024
	(in thousands)
Research and development	$	3,748	$	2,812
General and administrative		5,576		4,561
Total stock-based compensation	$	9,324	$	7,373

As of March 31, 2025, there was $73.6 million and $18.3 million of unrecognized stock-based compensation related to stock options and restricted stock outstanding, respectively, including stock options and restricted common stock for which achievement of milestones was not probable, which were expected to be recognized over a weighted-average remaining service period of 2.6 years and 2.0 years, respectively.