11.            STOCK-BASED COMPENSATION

Stock-Based Compensation

For stock options, the Company estimates the fair value of the awards on the date of grant using an option-pricing model. The portion of the award expected to vest is recognized as expense in the Company’s statements of operations and comprehensive loss over the requisite service period for time-based awards and upon determining that the performance condition is probable for performance-based awards. The Company estimates the fair value of stock-based compensation awards using the Black-Scholes model. This model requires the Company to estimate the expected volatility and value of its common stock and the expected term of the stock options, all of which are highly complex and subjective variables. The variables take into consideration, among other things, actual and projected stock option exercise behavior. For employees and directors, the expected life was calculated based on the simplified method as described by the SEC Staff Accounting Bulletin No. 110, Share-Based Payment. For other service providers, the expected life was calculated using the contractual term of the award. The Company’s estimate of expected volatility was based on the historical stock price of the Company. The Company has selected a risk-free rate based on the implied yield available on U.S. Treasury securities with a maturity equivalent to the expected term of the options.

For restricted stock awards, the Company determines the fair value using the Company’s adjusted closing stock price on the grant date.

Warrants

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

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The warrants outstanding at March 31, 2026 expire on October 3, 2030.

Stock Awards

The Company maintains several equity incentive plans, but currently grants stock options and restricted stock awards only under the 2020 Equity Incentive Plan, the 2021 Equity Incentive Plan, and the 2025 Equity Incentive Plan. No new awards are granted under the Company’s prior equity plans.

In May 2025, the Company’s stockholders approved the 2025 Equity Incentive Plan, which authorized 3,500,000 shares of common stock for future awards. The share reserve automatically increases each January 1, beginning in 2026 and ending in 2035, by 5% of the outstanding shares of common stock as of the last day of the preceding fiscal year. On January 1, 2026, 2,868,420 shares were added to the 2025 Plan. Following approval of the 2025 Plan, no additional shares will be added to the 2021 Equity Incentive Plan. As of March 31, 2026, 4,605,230 shares remained available for issuance under the Company’s equity incentive plans.

The plans are administered by the Board and its compensation committee, which determine the recipients, award types, number of shares, exercise price and vesting terms. Stock options are granted at an exercise price not less than the

closing price of the Company’s common stock on the grant date, generally vest over one to four years, and have a maximum term of ten years.

Stock Option Awards

The estimated weighted average fair value of the options granted during the three months ended March 31, 2026 and 2025 were approximately $21.61 and $12.73 per share, respectively.

The Company estimates the fair value of each option award using the Black-Scholes option-pricing model. The Company used the following assumptions to estimate the fair value of stock options issued during the three months ended March 31, 2026 and 2025:

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Employee and non-employee stock-based compensation expense was as follows:

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The Company does not recognize an income tax benefit as the Company believes that an actual income tax benefit may not be realized. For non-qualified stock options, the loss creates a timing difference, resulting in a deferred tax asset, which is fully reserved by a valuation allowance.

As of March 31, 2026, the total unrecognized fair value compensation cost related to non-vested stock options was approximately $66.1 million, which is expected to be recognized over a weighted average period of approximately 2.4 years. As of March 31, 2026, the Company had approximately $4.4 million of total unrecognized stock-based compensation expense related to performance-based options subject to the achievement of certain performance conditions over a one-year performance period. Compensation cost associated with these awards will be recognized only if and when the applicable performance conditions are determined to be probable of achievement. As of March 31, 2026, the Company concluded that achievement of the performance conditions was not considered probable, and accordingly, no stock-based compensation expense related to these awards has been recognized

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The following is a schedule summarizing employee and non-employee stock option activity for the three months ended March 31, 2026:

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The aggregate intrinsic value represents the difference between the exercise price of the options and the estimated fair value of the Company’s common stock for each of the respective periods.

Restricted Stock Units

The Company has granted restricted stock units (“RSUs”) under the 2025 Plan. Each outstanding RSU will be exchanged for one share of the Company’s common stock. The Company estimates the fair value of each restricted stock unit using the Company’s adjusted closing stock price on the grant date.

The following table summarizes the activity of the Company’s RSUs for the three months ended March 31, 2026:

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