In February 2020, the Company adopted the 2020 Equity Incentive Plan (the 2020 Plan). The 2020 Plan became effective on February 11, 2020. The 2020 Plan provides for a variety of stock-based compensation awards, including stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance bonus awards, performance stock unit awards, dividend equivalents, or other stock or cash based awards. Under the 2020 Plan, the Company generally grants stock-based awards with service-based vesting conditions only. Options and restricted stock unit awards granted typically vest over a four-year period, but may be granted with different vesting terms.

Following the effectiveness of the 2020 Plan, the Company ceased making grants under the 2014 Equity Incentive Plan (the 2014 Plan). However, the 2014 Plan continues to govern the terms and conditions of the outstanding awards granted under it. Shares of common stock subject to awards granted under the 2014 Plan that are forfeited or lapse unexercised and which following the effective date of the 2020 Plan were not issued under the 2014 Plan are available for issuance under the 2020 Plan.

In February 2020, the Company adopted the 2020 Employee Stock Purchase Plan (the ESPP). Under the ESPP, employees have the ability to purchase shares of the Company’s common stock through payroll deductions at a discount during a series of offering periods of 24 months, each comprised of four six-month purchase periods. The purchase price will be the lower of 85% of the closing trading price per share of the Company’s common stock on the first day of an offering period in which an employee is enrolled or 85% of the closing trading price per share on the purchase date, which will occur on the last trading day of each purchase period.

For the three months ended March 31, 2025, there were zero shares of common stock purchased under the ESPP. As of March 31, 2025, a total of 5,634,648 shares of common stock were available for future issuance under the ESPP. As of March 31, 2025, there was $4.0 million of unrecognized compensation cost related to the ESPP.

The following summarizes option activity under both the 2020 Plan and the 2014 Plan:


	Number of Shares underlying options			Weighted- average exercise price		Weighted- average remaining contractual term		Aggregate intrinsic value
						(in years)		(in thousands)
Balance, December 31, 2024		13,985,538		$	24.25		7.36	$	276,335
Options granted		2,859,335			40.96
Options exercised		(90,043	)		9.90
Options cancelled and forfeited		(20,198	)		32.48
Balance, March 31, 2025		16,734,632		$	27.17		7.59	$	170,683
Options vested and exercisable as of March 31, 2025		8,185,474		$	19.80		6.15	$	133,644

As of March 31, 2025, there was $179.6 million of unrecognized stock-based compensation expense related to unvested stock options that is expected to be recognized over a weighted-average period of 2.95 years.

Activity under the 2020 Plan with respect to the Company’s restricted stock units (RSUs) during the three months ended March 31, 2025 was as follows:


	Number of Shares			Weighted- average grant date fair value per share		Weighted- average remaining contractual term		Aggregate intrinsic value
						(in years)		(in thousands)
Balance, December 31, 2024		2,850,112		$	30.87		1.49	$	124,664
RSUs granted		1,277,655			41.05
RSUs vested		(271,536	)		27.22
RSUs forfeited		(13,774	)		32.34
Balance, March 31, 2025		3,842,457		$	34.50		1.61		135,869
Expected to vest as of March 31, 2025		3,842,457		$	34.50		1.61		135,869

The number of RSUs vested includes shares of common stock that the Company withheld to satisfy the minimum statutory tax withholding requirements. As of March 31, 2025, there was $125.6 million of total unrecognized compensation cost related to RSUs that is expected to be recognized over a weighted average period of 3.05 years.

Total stock-based compensation expense related to stock options, RSUs and the ESPP by function was as follows:


	Three Months Ended March 31,
	2025		2024
	(in thousands)
Research and development	$	16,380	$	10,244
General and administrative		8,704		5,964
Total	$	25,084	$	16,208