The Company’s 2020 Equity Incentive Plan (the “2020 Plan”) provides for the grant of incentive stock options, non-qualified options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares initially reserved for issuance under the 2020 Plan was (i) 2,200,000 shares (the “share pool”), plus (ii) the number of shares of common stock available for issuance under the Company’s 2016 Stock Incentive Plan (the “2016 Plan”) as of the effective date of the 2020 Plan, plus the number of shares of Common Stock underlying awards under the 2016 Plan that on or after the date of adoption expire or become unexercisable without delivery of shares, are forfeited to, or repurchased for cash, are settled in cash, or otherwise become available again for grant under the 2016 Plan, in each case, in accordance with its terms (up to an aggregate of 5,078,295 shares). As of June 30, 2026, 1,924,115 shares remained available for future grant under the 2020 Plan.

The share pool will automatically increase on January 1 of each year from 2021 to 2030 by the lesser of (i) four percent of the number of shares of our Common Stock outstanding as of the close of business on the immediately preceding December 31 and (ii) the number of shares determined by the board of directors on or prior to such date for such year. The number of shares reserved for issuance under the 2020 Plan was increased by 2,266,293 shares effective January 1, 2026.

The 2020 Plan is administered by the board of directors or, at the discretion of the board of directors, by a committee of the board of directors. The exercise prices, vesting and other restrictions are determined at the discretion of the board of directors, or its committee if so delegated. Stock options granted with service-based vesting conditions generally vest over four years and expire after ten years. The exercise price for stock options granted is not less than the fair value of Common Stock on the date of grant. The Company bases fair value of common stock on the quoted market price.

On October 21, 2020, the Company’s board of directors adopted and its stockholders approved the 2020 Employee Stock Purchase Plan (the “ESPP”), which became effective on October 21, 2020. The aggregate number of shares of Common Stock available for purchase pursuant to the exercise of options under the ESPP is 360,000 shares, plus an automatic annual increase, as of January 1 of each year from 2021 to 2030, equal to the lesser of one percent of the number of shares of Common Stock outstanding as of the close of business on the immediately preceding December 31 and (ii) the number of shares determined by the board of directors on or prior to such date for such year (up to a maximum of 3,220,520 shares). The number of shares reserved for issuance under the ESPP was increased by 566,573 shares effective January 1, 2026. As of June 30, 2026, 2,633,981 shares remained available for future grant under the ESPP.

Eligible employees may authorize payroll deductions of up to 15% of their eligible compensation during an offering period. The purchase of shares is done at a 15% discount on the lesser of (i) the Fair Market Value of a share of Stock on the first day of the offering period and (ii) the Fair Market Value of a share of Stock on the last day of the offering period. The Company currently holds two offering periods, September 1 and March 1, respectively. The Company recognized a de minimis amount of expense related to the ESPP for the three and six months ended June 30, 2026 and 2025.

During the three months ended June 30, 2026, the Company updated its methodology for estimating expected volatility used in the Black‑Scholes option pricing model to determine the fair value of stock-based compensation awards.

Previously, as disclosed in the Company’s Annual Report on Form 10‑K for the year ended December 31, 2025, the Company historically estimated expected volatility based on the historical volatility of a group of publicly traded peer companies. This approach was utilized because the Company did not have sufficient historical trading data for its common stock to provide a reasonable basis for estimating expected volatility.

During the current period, the Company determined that it now has adequate historical trading information to support the use of the volatility of its own common stock. Accordingly, the Company has commenced estimating expected volatility based on the historical volatility of its own share price over a period commensurate with the expected term of the awards. The Company believes this change better reflects the expected volatility of its common stock and is consistent with the guidance in ASC 718, Compensation—Stock Compensation.


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Research and development expenses	$	1,025	$	1,129	$	2,018	$	2,279
General and administrative expenses	1,525		1,604		2,915		3,146
	$	2,550	$	2,733	$	4,933	$	5,425