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(9) Stock-Based Compensation

The Company has two equity incentive plans: the 2012 Stock Incentive Plan and the Amended and Restated 2019 Equity Incentive Plan (the “Plan”). On April 8, 2026, the Company’s board of directors approved an amendment to the Plan to increase the number of authorized shares issuable under the Plan by 3,500,000 shares. This amendment was approved by the Company’s stockholders on June 9, 2026 at the 2026 Annual Meeting. New awards can only be granted under the Plan. At June 30, 2026, 5,294,404 shares of common stock were available for future issuances under the Plan. The Plan provides for the grant of incentive stock options, nonqualified stock options, restricted stock awards, restricted stock units and/or stock appreciation rights to employees, directors, and other persons, as determined by the Company’s board of directors. The Company estimates forfeitures that it expects will occur and adjusts expense for actual forfeitures in the periods they occur.

The Company measures employee and nonemployee stock-based awards at grant-date fair value and records compensation expense ratably over the vesting period of the award. The Company recorded stock-based compensation

expense in the following expense categories of the accompanying consolidated statements of operations and comprehensive loss (in thousands):

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Stock Options

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The Company’s stock options vest based on the terms in each award agreement and generally vest over four years and have a term of 10 years.

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The following table summarizes stock option activity:

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Included in outstanding options at June 30, 2026 were 317,553 stock options granted outside of the Plan. These grants were made pursuant to the Nasdaq inducement grant exception in accordance with Nasdaq listing rule 5635(c)(4). At June 30, 2026, the aggregate intrinsic value of outstanding options was $16,740 and exercisable options was $0.

The weighted average grant-date fair value per share of options granted was $0.52 during the six months ended June 30, 2026. The aggregate intrinsic value of options exercised was $0 for the six months ended June 30, 2026. At June 30, 2026, the total unrecognized compensation expense related to unvested employee and nonemployee stock option awards was $1.6 million, which is expected to be recognized in expense over a weighted-average period of approximately 2.8 years.

The fair value of each option was estimated on the date of grant using the Black-Scholes option pricing model and the weighted average assumptions in the table below:

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Restricted Stock Units

The Company has issued service-based and performance-based restricted stock units (“RSUs”). Vesting of the service-based RSUs is based on the terms in each award agreement and is generally over four years. Vesting of the performance-based RSUs is subject to continued service through 2026 and the achievement of certain performance milestones for fiscal year 2026. The amount of performance-based RSUs that will vest can range from 0% to 110% of the original number of RSUs granted. Expense for the performance-based RSUs is not recognized until the performance conditions are deemed probable of achievement. The Company has not recorded any expense related to the performance-based RSUs.

The following table summarizes the service-based RSUs for the Plan:

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The following table summarizes the performance-based RSUs for the Plan:

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Included in outstanding RSUs at June 30, 2026 were 200,445 RSUs granted outside of the Plan. These grants were made pursuant to the Nasdaq inducement grant exception in accordance with Nasdaq listing rule 5635(c)(4). The weighted average grant-date fair value per RSU granted was $0.82 during the six months ended June 30, 2026. The aggregate intrinsic value of RSUs outstanding was $1.5 million at June 30, 2026. The total unrecognized compensation expense at June 30, 2026 related to RSUs was $2.7 million, excluding unrecognized compensation expense associated with performance-based RSUs that are not deemed probable of achievement, which is expected to be recognized in expense over a weighted-average period of approximately 2.8 years.