Equity Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2023

Equity Incentive Plans

Schedule of Assumptions Used in the Black-Scholes Model

	Year Ended December 31,
	2023	2022
Risk-free interest rate	3.54% - 5.54%	2.65% - 4.20%
Expected volatility	75.40% - 116.96%	81.81% - 85.86%
Expected term (in years)	0.12 - 7.00	5.50 - 7.00
Expected dividend yield	0%	0%

Schedule of Stock-Based Compensation Expenses

	Year Ended December 31,
	2023		2022
Research and development	$	1,013	$	1,794
General and administrative		(75)		1,311
Total stock-based compensation	$	938	$	3,105

Schedule of Stock Option Activity

	Options Outstanding
				Weighted
				Average
		Weighted		Remaining
		Average		Contractual	Aggregate
		Exercise		Term	Intrinsic
	Shares	Price		(Years)	Value (in thousands)
Outstanding at December 31, 2022	3,352,803	$	5.32	7.8	$	—
Granted	330,266	$	2.39		$	—
Exercised	(1,500)	$	3.15		$	1
Forfeited/Cancelled/Expired	(516,353)	$	4.94		$	1
Outstanding at December 31, 2023	3,165,216	$	5.04	5.9	$	429
Vested and expected to vest at December 31, 2023	3,165,216	$	5.04	5.9	$	429
Exercisable at December 31, 2023	2,176,275	$	4.01	4.0	$	115

Schedule of restricted stock awards

		Weighted Avg
		Grant Date
	Shares	Fair Value
Outstanding at December 31, 2022	129,666	$	27.11
Granted	200,000	$	2.39
Forfeited/Cancelled	(27,341)	$	39.53
Vested and Issued as Common Stock	(102,325)	$	23.79
Outstanding at December 31, 2023	200,000	$	2.39