SHARE-BASED COMPENSATION

The Company previously granted stock options under its 2015 Stock Incentive Plan (the “2015 Plan”). As of June 30, 2026 there were 15,784 stock options outstanding under the 2015 Plan and no remaining stock options available to be granted under the 2015 Plan.

The 2019 Incentive Award Plan (as amended and restated, the “2019 Plan”) provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock, restricted stock units and other share-based awards. The 2019 Plan had 35,626 stock options and 2,899,866 restricted stock units (“RSUs”) outstanding as of June 30, 2026.

The number of shares available for issuance under the 2019 Plan initially equaled 158,333 shares of common stock. The 2019 Plan provides for an annual increase to the number of shares of common stock available for issuance on the first day of each calendar year beginning January 1, 2020 and ending on and including January 1, 2029 by an amount equal to the lesser of (i) 4% of the aggregate number of shares of common stock outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares of common stock as determined by the board of directors. As of June 30, 2026, the aggregate number of shares available for issuance under the 2019 Plan has been increased by 1,825,822 pursuant to this provision. Additionally, the number of shares available for issuance under the plan was increased by an additional 630,000 shares in connection with the amendment and restatement of the 2019 Plan approved at the Company’s annual meeting of stockholders on June 4, 2024 and by an additional 3,800,000 shares in connection with the amendment and restatement of the 2019 Plan approved at the Company’s annual meeting of stockholders on May 21, 2026. Any shares that are subject to awards outstanding under the Company’s 2006 Plan and 2015 Plan as of the effective date of the 2019 Plan that expire, lapse, or are terminated, exchanged for cash, surrendered, repurchased, or canceled without having been fully exercised or forfeited, to the extent so unused, will become available for award grants under the 2019 Plan. As of June 30, 2026, 2,284,462 shares were available to be issued under the 2019 Plan.

The purchase price of the shares under the 2019 ESPP, in the absence of a contrary designation, will be 85% of the lower of the fair market value of our common stock on the first trading day of the offering period or on the purchase date. As of June 30, 2026, we had issued 130,143 shares under the 2019 ESPP. As of June 30, 2026, 20,900 shares were available to be issued under the 2019 ESPP. The Company recognized share-based compensation expense related to the 2019 ESPP of less than $0.1 million during each of the six months ended June 30, 2026 and the six months ended June 30, 2025.

The 2021 Employment Inducement Incentive Award Plan (as amended, the “Inducement Award Plan”) provides for the grant of non-qualified stock options, stock appreciation rights, restricted stock, RSUs and other share-based awards to newly hired employees who have not previously been an employee or member of the board, or an employee who is being rehired following a bona fide period of non-employment by the Company. No more than 1,100,000 shares of the Company’s common stock may be issued under the Inducement Award Plan. As of June 30, 2026, 976,785 shares were

available to be issued under the Inducement Award Plan. The Inducement Award Plan had 96,201 stock options and 13,804 RSUs outstanding as of June 30, 2026.

The Company recorded employee and nonemployee share-based compensation expense as follows (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Employee	$	1,692	$	2,740	$	3,106	$	5,379
Nonemployee	152		197		287		379
	$	1,844	$	2,937	$	3,393	$	5,758

Share-based compensation expense is included in the following line items in the condensed statements of operations (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Research and development	$	450	$	398	$	832	$	901
General and administrative	1,394		2,539		2,561		4,857
	$	1,844	$	2,937	$	3,393	$	5,758

The following table summarizes activity in the Company’s stock option plans for the six months ended June 30, 2026:


	Outstanding Option Shares	Weighted-Average Exercise Price
Balance as of December 31, 2025	168,993	$	165.54
Granted	—	—
Exercised	—	—
Forfeited/canceled	(21,382)	270.63
Balance as of June 30, 2026	147,611	$	150.32

The fair value of each RSU was determined based on the closing market price of the Company’s common stock on the date of grant. The fair value of the RSUs will be recognized as expense over the requisite vesting period.

The following table summarizes the Company’s RSU activity for the six months ended June 30, 2026:


	RSU Awards	Weighted-Average Grant Date Fair Value
Unvested RSUs as of December 31, 2025	1,623,933	$	7.36
Granted	2,028,345	7.02
Forfeited	(18,118)	4.94
Vested	(720,490)	8.40
Unvested RSUs as of June 30, 2026	2,913,670	$	6.88

There was approximately $17.8 million of total unrecognized compensation cost related to unvested stock options and RSUs as of June 30, 2026, which is expected to be recognized over a weighted-average period of 2.2 years.