Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2024

Stock-Based Compensation

Schedule of stock-based compensation expense

Stock-based compensation expense as reflected in the Company’s condensed consolidated statements of operations and comprehensive loss was as follows (in thousands):

	Three months ended June 30,				Six months ended June 30,
	2024		2023		2024		2023
Research and development	$	307	$	106	$	540	$	301
General and administrative		740		638		1,409		1,907
Stock-based compensation expense included in operating expenses	$	1,047	$	744	$	1,949	$	2,208

Summary of stock option activity

The following is a summary of the Company’s stock option activity for the six months ended June 30, 2024:

		Weighted-		Weighted- average	Aggregate
		average		remaining contractual	intrinsic value
	Options	exercise price		term (in years)	(in thousands)
Outstanding at December 31, 2023	4,178,194	$	2.98	8.22	$	11
Granted	2,520,450		3.02
Exercised	(366,947)		1.33
Cancelled	(163,259)		2.63
Outstanding at June 30, 2024	6,168,438	$	3.10	8.61	$	3,751
Vested at June 30, 2024	2,356,788	$	3.61		$	1,976
Vested and expected to vest at June 30, 2024	6,168,438	$	3.10	8.61	$	3,751

The following is a summary of the Company’s stock option activity for the six months ended June 30, 2023:

		Weighted-		Weighted- average	Aggregate
		average		remaining contractual	intrinsic value
	Options	exercise price		term (in years)	(in thousands)
Outstanding at December 31, 2022	4,408,274	$	3.44	8.52	$	350
Granted	2,257,506		1.08
Exercised	(1,239,899)		1.18
Cancelled	(1,006,332)		2.73
Outstanding at June 30, 2023	4,419,549	$	3.03	8.70	$	1,454
Vested at June 30, 2023	2,132,303	$	3.34	5.37	$	476
Vested and expected to vest at June 30, 2023	4,419,549	$	3.03	8.70	$	1,454

Schedule of assumptions used in estimation of fair value

	Three months ended June 30,				Six months ended June 30,
	2024		2023		2024		2023
Risk-free interest rate	4.24 - 4.65	%	3.94	%	4.07 - 4.65	%	3.67 - 4.24	%
Volatility	72 - 76	%	72	%	72 - 76	%	72 - 74	%
Dividend yield	0.00	%	0.00	%	0.00	%	0.00	%
Expected term (years)	6 - 7		7		6 - 7		2 - 7

Summary of restricted stock units activity

The following table summarizes activity related to RSUs:

		Weighted- average
		grant date
	Number of shares	fair value
Unvested at December 31, 2023	155,797	$	8.25
Granted	437,025	$	2.77
Vested	(49,626)	$	8.58
Cancelled	(27,400)	$	2.28
Unvested at June 30, 2024	515,796	$	3.89