In September 2021, the Company’s Board of Directors adopted, and its stockholders approved, the 2021 Incentive Award Plan (the 2021 Plan). Upon the adoption of the 2021 Plan, the Company restricted the grant of future equity awards under the 2020 Equity Incentive Plan (the 2020 Plan).

The 2021 Plan provides for the grants of stock options, RSUs and other equity-based awards to employees, non-employee directors and consultants of the Company. Shares that are forfeited or expired under the 2020 Plan are added back to the 2021 Plan share reserve. In addition, the number of shares of the Company’s common stock available for issuance under the 2021 Plan automatically increases on the first day of each fiscal year, beginning with the Company’s 2022 fiscal year, in an amount equal to the lesser of (1) 5% of the outstanding shares of the Company’s common stock on the last day of the immediately preceding fiscal year, or (2) such smaller amount as determined by the Company’s Board of Directors. The Company issues new shares of common stock upon exercise of options and vesting of RSUs. As of June 30, 2026, 1,746,962 shares were available for future grant under the 2021 Plan.

A summary of the Company’s stock option activity for the period ended June 30, 2026 is as follows (in thousands, except share and per share data and years):


	Options			Weighted-Average Exercise Price per Share		Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value
Outstanding at December 31, 2025		13,617,445		$	12.58		8.0	$	186,669
Granted		2,726,346		$	33.43
Exercised		(1,219,678	)	$	11.44
Forfeited and expired		(714,749	)	$	14.33
Outstanding at June 30, 2026		14,409,364		$	16.54		7.8	$	226,331
Exercisable at June 30, 2026		6,473,183		$	11.74		6.3	$	130,844
Vested and expected to vest as of June 30, 2026		14,409,364		$	16.54		7.8	$	226,331

The total intrinsic value of stock options exercised during the six months ended June 30, 2026 and 2025 was $28.0 million and $3.3 million, respectively.

The fair value of stock options was estimated using the following assumptions:


	Six Months Ended June 30,
	2026	2025
Risk-free rate of interest	3.7 - 4.3%	3.8 - 4.4%
Expected term (years)	5.3 - 6.1	5.3 - 6.1
Expected stock price volatility	72.9 - 81.9%	86.3 - 95.4%
Dividend yield	—	—

The weighted-average grant date fair value of options granted for the six months ended June 30, 2026 and 2025 was $23.37 and $8.30 per share, respectively.

RSUs are share awards that, upon vesting, will deliver to the holder shares of our common stock. The Company began issuing RSUs in 2026. The RSUs generally vest annually over four years provided the individual remains in continuous service of the Company. The fair value of RSUs is based on the closing price of the

Company's common stock on the grant date. A summary of the Company’s RSU activity for the period ended June 30, 2026 is as follows:


	RSUs			Weighted-Average Grant Date Fair Value
Outstanding at December 31, 2025		—		$	—
Granted		487,467		$	33.93
Vested		—		$	—
Forfeited		(31,717	)	$	33.93
Outstanding at June 30, 2026		455,750		$	33.93

In September 2021, the Company’s Board of Directors adopted, and its stockholders approved, the 2021 Employee Stock Purchase Plan (ESPP). The ESPP permits eligible employees who elect to participate in an offering under the ESPP to have up to 15% of their eligible earnings withheld, subject to certain limitations, to purchase shares of common stock pursuant to the ESPP. The price of common stock purchased under the ESPP is equal to 85% of the lower of the fair market value of the common stock at the commencement date of each offering period or the relevant date of purchase. As of June 30, 2026, there were 2,442,458 shares available for future purchase under the ESPP.

Stock-based compensation expense recognized for all equity awards, including stock options, RSUs and ESPP, has been reported in the condensed statements of operations and comprehensive loss as follows (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Research and development expense	$	5,770	$	3,690	$	10,277	$	7,368
General and administrative expense		4,462		2,690		7,802		5,434
Total	$	10,232	$	6,380	$	18,079	$	12,802

For the six months ended June 30, 2026 and 2025, stock-based compensation expense reversals related to award forfeitures were immaterial.

As of June 30, 2026, unrecognized compensation cost related to stock options and RSUs was $115.6 million and $14.9 million, respectively, and is expected to be recognized as expense over weighted-average periods of 2.7 years and 3.8 years, respectively.