In June 2021, the Company adopted the 2021 Employee, Director and Consultant Equity Incentive Plan, as amended (the “2021 Plan”), that authorized the Company to grant up to 803,564 shares of common stock via stock-based compensation awards. In 2022, the Company amended the 2021 Plan and increased the total number of shares authorized under the 2021 Plan to 2,748,818. In January 2024, the Company adopted the 2024 Employee, Director and Consultant Equity Incentive Plan (the “2024 Plan”) that authorized the Company to grant up to 3,900,000 shares of common stock plus any remaining ungranted or forfeited shares from the 2021 Plan. As of June 30, 2025, there were 3,542,962 shares available to be granted. The Company’s stock options vest based on the terms in the awards agreements and generally vest over four years. The Company recorded stock-based compensation expense in the following expense categories in its accompanying statements of operations and comprehensive loss (in thousands):

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The following is a summary of stock options activity:

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The weighted-average grant-date fair value of options granted in the first six months of 2025 and 2024 were $21.31 and $7.49 per share, respectively. The fair value was estimated using the Black-Scholes option-pricing model based on the following assumptions:

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(a) Subsequent to the Company’s initial public offering on January 24, 2024, the fair value of common stock is based on the closing market price of common stock at the date of grant.

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Unrecognized compensation cost for awards not vested as of June 30, 2025 was $44.1 million and will be expensed over a weighted-average period of 2.93 years.