For the three and six months ended June 30, 2025 and 2024, the Company recorded stock-based compensation expense as follows (in thousands):


	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2025		2024		2025		2024
Research and development	$	904	$	403	$	1,329	$	912
Selling, general and administrative		6,693		4,005		12,118		11,744
Total stock-based compensation	$	7,597	$	4,408	$	13,447	$	12,656

As of June 30, 2025, there were outstanding stock options to purchase 12,177,015 shares of common stock, of which stock options to purchase 7,119,649 shares of common stock were exercisable.

During the three and six months ended June 30, 2025, the Company granted seven-year term options to purchase an aggregate of 180,447 and 691,403 shares, respectively, of the Company’s common stock to employees. The Company recorded stock-based compensation related to stock options totaling $6.1 million and $10.9 million, respectively, during the three and six months ended June 30, 2025.

During the three and six months ended June 30, 2024, the Company granted seven-year term options to purchase an aggregate of 47,500 and 840,995 shares, respectively, of the Company’s common stock to employees. The Company recorded stock-based compensation related to stock options totaling $3.6 million and $9.0 million, respectively, during the three and six months ended June 30, 2024.

During the three and six months ended June 30, 2025, options to purchase 406,372 shares and 1,381,527 shares, respectively, of the Company’s common stock were exercised, with proceeds of $2.2 million and $7.0 million, respectively, to the Company.

During the three and six months ended June 30, 2024, options to purchase 491,840 shares and 1,156,272 shares, respectively, of the Company’s common stock were exercised, with proceeds of $2.0 million and $3.6 million, respectively, to the Company.

As of June 30, 2025, there was approximately $36.7 million of unrecognized compensation expense related to non-vested stock option awards granted under the 2018 Stock Incentive Plan. The cost is expected to be recognized over a weighted average period of approximately 2.5 years.

The Company granted 15,261 restricted stock units and 18,700 restricted stock units during the three and six months ended June 30, 2025, respectively. The Company granted no restricted stock units and 35,693 restricted stock units during the three and six months ended June 30, 2024. During the three and six months ended June 30, 2025, the Company recorded non-cash stock-based compensation expense related to restricted stock units totaling $1.5 million and $2.5 million, respectively. During the three and six months ended June 30, 2024, the Company recorded non-cash stock-based compensation expense related to restricted stock units totaling $0.8 million and $3.7 million, respectively.

As of June 30, 2025, there was approximately $7.1 million of unrecognized compensation expense related to non-vested restricted stock units granted under the 2018 Stock Incentive Plan. The cost is expected to be recognized over a weighted average period of approximately 2.7 years.