11. Stock-Based Awards

For the three and six months ended June 30, 2026, the Company had three stock-based compensation plans under which it was able to grant stock-based awards, the 2021 Stock Incentive Plan, as amended (the “2021 Plan”), the 2019 Inducement Stock Incentive Plan, as amended (the “2019 Inducement Plan”), and the Amended and Restated 2014 Employee Stock Purchase Plan (the “ESPP”) (collectively, the “Stock Plans”). The 2021 Plan and the 2019 Inducement

Plan provide for the grant of non-statutory stock options, restricted stock awards, restricted stock units (“RSUs”), performance stock units (“PSUs”), stock appreciation rights and other stock-based awards. The 2021 Plan also provides for the grant of incentive stock options.

The terms and conditions of the Stock Plans are described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025, filed with the SEC on February 5, 2026. Subsequent updates to the Stock Plans during the six months ended June 30, 2026 are as follows:

2019 Plan — On February 4, 2026, the Company's board of directors amended the 2019 Inducement Plan to increase the aggregate number of shares issuable thereunder from 6,054,000 to 7,028,000 shares of common stock.

2021 Plan — On June 10, 2026, the Company’s stockholders approved an amendment to the 2021 Plan to increase the aggregate number of shares of common stock issuable thereunder by 10,000,000 shares of common stock.

As of June 30, 2026, 11,932,484, 454,699, and 2,075,397 shares of common stock remained available for issuance under the 2021 Plan, the 2019 Inducement Plan, and the ESPP, respectively.

Stock options, RSUs and PSUs

During the three and six months ended June 30, 2026, the Company granted options to purchase 987,074 and 5,927,103 shares of common stock, respectively, at a weighted exercise price of $8.99 and $11.23 per share, respectively. Of these, options to purchase 317,249 and 4,767,253 shares of common stock, respectively, were granted under the 2021 Plan, and options to purchase 669,825 and 1,159,850 shares of common stock, respectively, were granted under the 2019 Inducement Plan.

During the three and six months ended June 30, 2026, the Company granted 488,816 and 2,126,884 RSUs, respectively. Of these, 267,291 and 1,744,784 RSUs, respectively, were granted under the 2021 Plan and 221,525 and 382,100 RSUs, respectively, were granted under the 2019 Inducement Plan. Each RSU is settleable for one share of common stock upon vesting.

On February 11, 2025, the Company granted 1,500,000 PSUs to its Executive Chairman, President and Chief Executive Officer under the 2021 Plan. Each PSU is settleable for one share of common stock upon vesting. The PSUs are allocated equally across four tranches, which can be earned during a five-year performance period commencing on the grant date (the “PSU Performance Period”), if the Company’s consecutive 60-day closing stock price average meets or exceeds per share price hurdles of $15.00, $20.00, $25.00 and $30.00, as applicable. All PSUs are subject to a service condition. The PSUs earned during the first three years of the PSU Performance Period are subject to additional service-based vesting requirements through February 11, 2028.

On February 11, 2025, the Company granted 2,750,000 performance stock options to the Company’s Executive Chairman, President and Chief Executive Officer under the 2021 Plan (the “Performance Option Award”). The Performance Option Award was contingent upon the approval by the Company’s stockholders of Amendment No. 4 to the 2021 Plan. The stockholders of the Company approved Amendment No. 4 to the 2021 Plan on June 11, 2025. In accordance with the guidance of Accounting Standards Codification Topic 718 Compensation—Stock Compensation, the Performance Option Award was deemed granted for financial accounting purposes as of June 11, 2025 when shareholder approval was obtained. The Performance Option Award is allocated equally across four tranches, which can be earned during a five-year performance period commencing on February 11, 2025 (the “Option Award Performance Period”), if the Company’s consecutive 60-day closing stock price average meets or exceeds per share price hurdles of $15.00, $20.00, $25.00 and $30.00, as applicable. All performance stock options are subject to a service condition. The performance stock options earned during the first three years of the Option Award Performance Period are subject to additional service-based vesting requirements through February 11, 2028.

The fair value of each tranche of the PSUs and each tranche of the Performance Option Award was estimated using a Monte Carlo simulation. The main inputs to valuing each tranche include the risk-free interest rate, expected volatility, the contractual term of five years, and no expected dividend yield. The requisite service period for each tranche was derived from the Monte Carlo simulation, taking into account the three-year minimum service requirement.

During the three and six months ended June 30, 2026, 1,483,502 and 1,903,178 stock options, respectively, and 135,856 and 188,322 RSUs, respectively, expired or were forfeited.

Stock-based Compensation

The Company recorded stock-based compensation expense related to stock options, RSUs and PSUs in the following expense categories of its unaudited condensed consolidated statements of operations and comprehensive loss:

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As of June 30, 2026, the Company had an aggregate of $105,025 of unrecognized stock-based compensation cost, which is expected to be recognized over a weighted average period of 2.41 years.