Stock-Based Compensation | 11. Stock-Based Compensation Equity Incentive Award Plans In March 2021, the Company’s board of directors and stockholders adopted the 2021 Equity Incentive Plan (the “2021 Plan”), which became effective on March 25, 2021, the date of the underwriting agreement related to the Company’s IPO. Upon adoption of the 2021 Plan, the Company restricted future grants from its 2018 Plan. Under the 2021 Plan, the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units, performance stock awards, performance cash awards and other forms of stock awards to employees, directors and consultants, including employees and consultants of the Company’s affiliates. The number of shares of common stock available for issuance under the 2021 Plan will automatically increase on January 1 of each calendar year, starting on January 1, 2022 through January 1, 2031, in an amount equal to 5% of the total number of shares of the Company’s common stock on the last day of the calendar month before the date of each automatic increase, or a lesser number of shares determined by the Company’s board of directors . As of March 31, 2022 , the total number of shares available for future issuance was 6,376,288 . The following table summarizes stock option activity for the three months ended March 31, 2022: Options Weighted-Average Exercise Price Outstanding as of December 31, 2021 2,673,775 $ 8.49 Granted 2,497,783 $ 12.93 Exercised ( 99,929 ) $ 1.56 Forfeited ( 10,000 ) $ 20.89 Balance at March 31, 2022 5,061,629 $ 10.79 Stock-based compensation expense has been reported in the Company's condensed statements of operations as follows (in thousands): Three Months Ended March 31, 2022 2021 Research and development $ 1,036 $ 164 General and administrative 1,324 483 Total $ 2,360 $ 647 2021 Employee Stock Purchase Plan In March 2021, the Company’s board of directors and stockholders adopted the ESPP, which became effective on March 25, 2021, the date of the underwriting agreement related to the Company’s IPO. The ESPP permits eligible employees who elect to participate in an offering under the ESPP to have up to 15 % of their eligible earnings withheld, subject to certain limitations, to purchase shares of common stock pursuant to the ESPP. The price of common stock purchased under the ESPP is equal to 85 % of the lower of the fair market value of the common stock at the commencement date of each offering period or the relevant date of purchase. A total of 600,000 shares of common stock were approved to be initially reserved for issuance under the ESPP. In addition, the number of shares of common stock available for issuance under the ESPP will automatically increase on January 1 of each calendar year, starting on January 1, 2022 through January 1, 2031, in an amount equal to the lesser of (i) 1% of the total number of shares of the Company’s common stock on the last day of the calendar month before the date of each automatic increase and (ii) 1,200,000 shares; provided that before the date of any such increase, the Company’s board of directors may determine that such increase will be less than the amount set forth in clauses (i) and (ii) . As of March 31, 2022 , the Company had issued 11,456 shares of the Company's common stock under the ESPP and had 1,145,361 shares available for future issuance. |