STOCK-BASED COMPENSATION | NOTE 10. STOCK-BASED COMPENSATION The Company can grant stock-vested awards under its 2021 Equity Incentive Plan (“2021 Plan”), 2021 Employee Stock Purchase Plan (“ESPP”) and the 2022 Inducement Equity Incentive Plan, as amended (the “2022 Inducement Plan”). As of March 31, 2024, 892,650 shares were reserved for issuance under the 2021 Plan, of which 109,172 shares were available for future grant and 783,478 shares were subject to outstanding options, including performance-based awards. As of March 31, 2024, 18,941 shares have been issued under the ESPP and 166,958 shares were reserved and available for future issuance. As of March 31, 2024, 550,000 shares were reserved for issuance under the 2022 Inducement Plan, of which 81,885 shares were available for future grant and 468,115 shares were subject to outstanding stock options. Under the 2021 Plan, the Company can grant incentive stock options, nonstatutory stock options, restricted stock awards, stock appreciation rights, restricted stock units (“RSUs”), performance awards and other awards to employees, directors and consultants. Under the 2022 Inducement Plan, the Company can grant nonstatutory stock options, restricted stock awards, stock appreciation rights, RSUs, performance awards and other awards, but only to an individual, as a material inducement to such individual to enter into employment with the Company or an affiliate of the Company, who (i) has not previously been an employee or director of the Company or (ii) is rehired following a bona fide period of non-employment with the Company. Under the ESPP, the Company can grant purchase rights to employees to purchase shares of common stock at a purchase price which is equal to 85% of the fair market value of common stock on the offering date or on the exercise date, whichever is lower. Stock Option Activity The following table summarizes the stock option activities, including performance-based stock options, under the 2021 Plan, the 2022 Inducement Plan and the Company’s 2019 Equity Incentive Plan (the “2019 Plan”) for the three months ended March 31, 2024: Options Weighted Weighted Aggregate Balance, December 31, 2023 1,040,875 $ 19.82 8.55 $ 237 Options granted 402,017 $ 17.78 Options exercised (21,657 ) $ 7.15 Options cancelled/forfeited (22,904 ) $ 22.51 Balance, March 31, 2024 1,398,331 $ 19.39 8.71 $ 15,516 Vested and expected to vest, March 31, 2024 1,398,331 $ 19.82 8.71 $ 15,516 Exercisable, March 31, 2024 391,014 $ 21.49 7.29 $ 3,998 The aggregate intrinsic value represents the difference between the estimated fair value of the underlying common stock and the exercise price of outstanding, in-the-money options. The total intrinsic value of the options exercised during the three months ended March 31, 2024 and 2023 was $0.4 million and $0.1 million, respectively. The total fair value of options that vested during the three months ended March 31, 2024 and 2023 was $1.7 million and $1.5 million, respectively. The weighted-average grant date fair value of options granted during the three months ended March 31, 2024 and 2023 was $15.17 and $15.19 per share, respectively. Future stock-based compensation for unvested options as of March 31, 2024 was $14.0 million, which is expected to be recognized over a weighted-average period of 3.1 years, including $0.1 million related to performance-based stock options, which is expected to be recognized over a weighted-average period of 0.8 years. Performance-based stock options The following table summarizes the performance-based stock options activity under the 2021 Plan and the 2019 Plan for the three months ended March 31, 2024: Options Weighted Weighted Aggregate Balance, December 31, 2023 46,394 $ 14.19 7.06 $ 24 Options granted — $ Options cancelled/forfeited — $ Balance, March 31, 2024 46,394 $ 14.19 7.06 $ 709 Vested and expected to vest, March 31, 2024 46,394 $ 14.19 7.06 $ 709 Exercisable, March 31, 2024 31,393 $ 7.78 6.46 $ 682 Restricted Stock Units (RSUs) As of December 31, 2023 the Company had no unvested outstanding RSUs under the 2021 Plan and no RSUs were granted during the three months ended March 31, 2024. Employee Stock Purchase Plan The Company issued no shares of common stock under the ESPP during each of the three months ended March 31, 2024 and 2023, and recognized less than $0.1 million compensation expense related to the ESPP during each of the three months ended March 31, 2024 and 2023. Unamortized stock-based compensation for shares issuable under the ESPP as of March 31, 2024 was less than $0.1 million, which is expected to be recognized over a weighted-average period of 0.2 years. The Company recorded $0.1 million in accrued expenses and other current liabilities related to contributions withheld as of March 31, 2024. Stock-Based Compensation Expense The following table presents stock-based compensation expenses related to options and RSUs granted to employees and non-employees, ESPP awards and restricted common stock shares issued to founders (in thousands): Three Months Ended 2024 2023 General and administrative $ 820 $ 799 Research and development 349 468 Total $ 1,169 $ 1,267 The Company recognized less than $0.1 million of stock-based compensation income related to performance-based options and RSUs during each of the three months ended March 31, 2024 and 2023. Valuation of Stock Options The grant date fair value of stock options was estimated using a Black-Scholes option-pricing model with the following assumptions: Three Months Ended 2024 2023 Expected term (in years) 6.04 – 6.08 5.25 – 6.08 Expected volatility 112 % 103% – 104 % Risk-free interest rate 3.93% – 4.27 % 3.45% – 4.25 % Expected dividend yield — — Valuation of ESPP Awards No ESPP awards were granted during the three months ended March 31, 2024 and 2023. |