8. Stock-Based Compensation

2024 Equity Incentive Plan

The 2024 Equity Incentive Plan (“2024 Plan”) was adopted on February 6, 2024. The 2024 Plan provided for the Company to grant stock options, restricted stock awards, restricted stock units, and other stock-based awards to employees, officers, directors, consultants, and advisors. Equity incentive stock options granted under the 2024 Plan generally vest over four years, subject to the participant’s continued service, and expire after ten years. As of March 31, 2026 and December 31, 2025, 1,155,540 and 1,167,826 shares, respectively, were subject to options outstanding under the 2024 Plan and will become available under the 2024 Stock Incentive Plan (defined below) to the extent the options are forfeited or lapse unexercised.

2024 Stock Incentive Plan

The 2024 Stock Incentive Plan (“2024 Stock Plan”) became effective in August 2024. The 2024 Stock Plan allows for the grant of stock options, stock appreciation rights, restricted stock awards, restricted stock units, other stockholder-based awards and incentive bonuses. An additional 3,354,715 shares became available for issuance under the 2024 Stock Plan on January 1, 2026 as a result of the annual increase pursuant to the evergreen provision.

As of March 31, 2026, 10,667,146 shares were reserved for issuance under the 2024 Stock Plan, of which 6,129,190 shares were available for future grant and 4,537,956 shares were subject to outstanding options and restricted stock units. As of December 31, 2025, 7,383,349 shares were reserved for issuance under the 2024 Stock Plan, of which 4,600,217 shares were available for future grant and 2,783,132 shares were subject to outstanding options.

2024 Employee Stock Purchase Plan

The 2024 Employee Stock Purchase Plan (the “ESPP”) became effective in August 2024. Eligible employees may purchase shares of common stock under the ESPP at 85% of the lower of the fair market value of the common stock as of the first or the last day of each offering period. Employees are limited to contributing 15% of the employee’s eligible compensation and may not purchase more than $25,000 of stock during any calendar year. The ESPP will terminate ten years from the first purchase date under the plan, unless terminated earlier by the Board.

The Company issued no shares during the three months ended March 31, 2026 and 2025, out of the ESPP. As of each of March 31, 2026 and December 31, 2025, there were 975,922 shares of common stock available in the pool for future issuances.

For each of the three months ended March 31, 2026 and March 31, 2025, stock-based compensation expenses related to the ESPP were less than $0.1 million.

Stock Option Valuation

The following table summarizes the weighted-average assumptions used in calculating the fair value of the awards for the three months ended March 31, 2026 and 2025:

Stock Option Activity

The following table summarizes the stock option activities under the 2024 Plan and the 2024 Stock Plan for the three months ended March 31, 2026:

The weighted average grant-date fair value per share of stock options granted during the three months ended March 31, 2026 was $25.68 per share.

The aggregate intrinsic value represents the difference between the closing price of the Company’s common stock on March 31, 2026 and the exercise price of outstanding, in-the-money employee stock options.

The aggregate intrinsic value of the options exercised during the three months ended March 31, 2026 and 2025 were $1.4 million and nil, respectively.

Restricted Stock Units

The Company began issuing restricted stock units (“RSUs”) under the 2024 Stock Plan during the quarter ended March 31, 2026. An RSU is an agreement to issue shares of the Company’s common stock at the time of vesting. RSUs generally vest over a four-year service period. RSUs granted during the annual refresher awards vest typically in equal quarterly installments over four years, subject to continued employment. RSUs granted to a new employee cliff vest 25% on the Company’s quarterly vesting date on or after the first anniversary of the grant date, followed by 12 equal quarterly vesting thereafter. Upon vesting, each RSU converts into one share of the Company’s common stock.

Stock-based compensation expense associated with RSUs are based on the fair value of the Company’s common stock on the grant date, which equals the closing market price of the Company’s common stock on the grant date. For RSUs, the Company recognizes compensation expense over the vesting period of the awards that are ultimately expected to vest.

The following table summarizes the RSU activity for the three months ended March 31, 2026:

The fair value of RSUs that vested during the three months ended March 31, 2026 was $1.0 million.

For the three months ended March 31, 2026 and March 31, 2025, stock-based compensation expenses related to RSUs was $1.0 million and nil, respectively.

Restricted Stock Awards

The following table summarizes the restricted stock awards (“RSA”) activity for the three months ended March 31, 2026:

The fair value of RSAs that vested during the three months ended March 31, 2026 was $4.5 million.

For the three months ended March 31, 2026 and March 31, 2025, stock-based compensation expenses related to RSAs were less than $0.1 million.

Option Agreements and Paruka Warrant Obligation

As part of the Option Agreements (defined in Note 10 below), the Company granted warrants to purchase a number of shares equal to 1.00% of outstanding shares as of the date of the grant on a fully-diluted basis, or based upon the agreed number of warrants as disclosed in the Warrant Agreement, with an exercise price equal to the fair market value of the underlying shares on the grant date (the “Paruka Warrant Obligation”).

The grant dates for the issuance of warrants were expected to be December 31, 2024 and December 31, 2025 as all terms of the award, including number of shares and exercise price, will be known by all parties. The Company determined that the 2024 and 2025 grants are two separate grants, as there would be no obligation for the 2025 grant had the Company exercised or terminated all of the options under the Option Agreements prior to December 31, 2024. The service inception period for the grant precedes the grant date, with the full award being vested as of the grant date with no post-grant date service requirement. Accordingly, a liability related to the Paruka Warrant Obligation was recorded during the 2024 and 2025 interim periods. The liability is adjusted to fair value at the end of each interim reporting period, with changes in fair value recorded in the consolidated statements of operations as stock-based compensation expenses under research and development expenses.

The Company settled its 2024 and 2025 obligations under the Paruka Warrant Obligation by issuing Paruka 596,930 and 375,000 warrants, respectively, to purchase common stock at an exercise price per warrant of $19.39 and $30.18, respectively. For the three months ended March 31, 2026 and 2025, nil and $1.4 million, respectively, was recognized as stock-based compensation expense related to the Paruka Warrant Obligation. As of each of March 31, 2026 and December 31, 2025, the unamortized expense related to the Paruka Warrant Obligation was nil.

Employee Warrants

The following table summarizes the employee warrant activity during the three months ended March 31, 2026:

The aggregate intrinsic value represents the difference between the closing price of the Company’s common stock as of March 31, 2026 and the exercise price of outstanding, in-the-money warrants.

The aggregate intrinsic value of the employee warrants exercised during the three months ended March 31, 2026 and 2025 was $3.5 million and nil, respectively.

Stock-Based Compensation Expense

The following table summarizes the classification of the Company’s stock-based compensation expense in the condensed consolidated statements of operations (in thousands):

As of March 31, 2026, total unrecognized stock-based compensation expenses related to the unvested stock options, RSUs, RSAs, employee warrants, and ESPP was $84.1 million, which is expected to be recognized over a weighted average period of approximately 3.1 years.

The following table summarizes the award types of the Company’s stock-based compensation expense in the condensed consolidated statements of operations (in thousands):