Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2024

Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]

Summary of Stock-based Compensation Expense

Total stock-based compensation expense recorded as research and development and general and administrative expenses, respectively, for employees, directors and non-employees is as follows (in thousands):

	Three Months Ended March 31,
	2024		2023
Research and development	$	1,543	$	345
General and administrative		2,515		679
Total stock-based compensation expense	$	4,058	$	1,024

Summary of Unrecognized Stock-based Compensation

The following table summarizes unrecognized stock-based compensation expense as of March 31, 2024.

	Unrecognized Expense (In Thousands)		Weighted-Average Remaining Period of Recognition (In Years)
Restricted stock units	$	22,595		3.87
Stock options		30,753		3.37
Total unrecognized equity-based compensation expense	$	53,348

Schedule of Restricted Stock Unit Activity

A summary of restricted common stock activity is as follows:

	Three Months Ended March 31,
	2024		2023
Unvested at the beginning of the year		—		1,916
Vested		—		(958	)
Unvested at the end of the period		—		958

Schedule of Stock Option Activity

The following table summarizes stock option activity for the three months ended March 31, 2024.

	Number of Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In Years)		Aggregate Intrinsic Value (In Thousands)
Outstanding at December 31, 2023		2,459,037		$	13.82		7.81	$	109,078
Granted		616,871			64.59
Exercised		(95,467	)		8.44
Forfeited		(30,924	)		50.32
Expired		(1,244	)		14.51
Outstanding at March 31, 2024		2,948,273		$	24.23		8.05	$	114,368
Exercisable at March 31, 2024		1,329,424		$	10.67		6.99	$	69,546

Summary of Fair Value of Stock Option Granted

The weighted-average assumptions used to estimate the fair value of stock options granted were as follows:

	Three Months Ended March 31,
	2024			2023
Risk-free interest rate		4.01	%		3.86	%
Expected term (in years)		6.03			6.05
Expected volatility		58	%		62	%
Expected dividend yield		0	%		0	%
Fair value per share of common stock	$	64.59		$	23.10

Restricted stock units [Member]

Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]

Schedule of Restricted Stock Unit Activity

The following table summarizes restricted stock unit activity for the three months ended March 31, 2024.

	Number of Units			Weighted- Average Grant Date Fair Value
Restricted stock units as of December 31, 2023		—		$	-
Granted		371,034		$	64.14
Forfeited		(2,320	)	$	63.90
Restricted stock units as of March 31, 2024		368,714		$	64.14