As of September 30, 2024, the Company had 2,635,312 shares of its common stock available for future issuance under the 2023 Inducement Plan.

As of September 30, 2024, the Company had 2,457,705 shares of its common stock available for future issuance under its 2021 Equity Incentive Plan.

The Company’s stock options generally vest over 48 months with 25% vesting after one year followed by ratable monthly vesting over the remaining three years and have a contractual term of 10 years. The weighted-average assumptions used principally in determining the fair value of options granted were as follows:


	Nine Months Ended September 30,
	2024			2023
Expected term (in years)		6.0			6.0
Expected volatility		88.9	%		81.7	%
Risk-free interest rate		4.1	%		3.8	%
Dividend yield		—			—

During the nine months ended September 30, 2024 and 2023, the Company granted stock options to purchase 2,174,100 shares and 2,247,844 shares of its common stock, respectively, with a weighted-average grant-date fair value of $1.49 and $3.65 per share,

respectively. As of September 30, 2024, total unrecognized compensation expense related to stock options was $9.3 million, which is expected to be recognized over a weighted-average period of 2.5 years.

As of September 30, 2024, options for 2,575 shares of Company common stock with a weighted-average exercise price of $4.90 were exercised and unvested. An immaterial amount of underlying proceeds from the unvested exercises is recorded in other current liabilities on the condensed consolidated balance sheet.

During the nine months ended September 30, 2024 and 2023, the Company granted 1,196,217 restricted stock units and 659,672 restricted stock units, respectively, with a weighted-average grant date fair value of $2.29 and $5.49 per share, respectively. As of September 30, 2024, total unrecognized compensation expense related to restricted stock units was $3.9 million, which is expected to be recognized over a weighted-average period of 2.4 years.

As of September 30, 2024, the Company had 1,894,294 shares of its common stock available for issuance under its Employee Stock Purchase Plan (“ESPP”).

During the nine months ended September 30, 2024, the Company issued 74,326 shares of common stock with a weighted-average purchase price of $1.48 under the ESPP, which resulted in an immaterial amount of compensation expense. During the nine months ended September 30, 2023, the Company issued 44,977 shares of common stock with a weighted-average purchase price of $3.76 under the ESPP, which resulted in an immaterial amount of compensation expense.

Stock-based compensation expense was allocated as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands)	2024		2023		2024		2023
Research and development	$	1,148	$	1,527	$	3,825	$	6,345
General and administrative		1,116		1,635		4,313		5,123
Total stock-based compensation expense	$	2,264	$	3,162	$	8,138	$	11,468