In February 2021, the Company adopted the 2021 Plan for the issuance of stock options granted to the Company’s key directors, officers, employees and consultants, as a means to secure the benefits arising from capital stock ownership. In connection with the Company’s IPO in November 2023, the Company adopted the 2023 Equity Incentive Plan (the “2023 Plan”) and the 2023 ESPP (together with the 2021 Plan and 2023 Plan, the “Plans”) for the issuance of equity awards granted to the Company's key directors, officers, employees, and consultants, and for the issuance of shares purchased under the 2023 ESPP to the Company's employees, respectively, as a means to secure the benefits arising from capital stock ownership. The purposes of the Plans are to promote the alignment of the interests of key directors, officers, employees, and consultants with the success of the Company and to provide compensation opportunities to attract, retain and motivate directors, officers, employees, and consultants of the Company.

The Company’s Board of Directors adopted the 2023 Plan and the 2023 ESPP in October 2023, and the Company’s stockholders approved the 2023 Plan and the 2023 ESPP in October 2023. In connection with the IPO, the Company’s 2023 Equity Incentive Plan (the “2023 Plan”) and its 2023 Employee Stock Purchase Plan (the “2023 ESPP”) became effective. Upon the effectiveness of the 2023 Plan and the 2023 ESPP:

Upon adoption, the maximum number of shares of common stock that may be issued under the 2023 Plan was initially 4,737,000 shares, which was approximately the sum of (i) 1,803,980 new shares, plus (ii) the 2021 Plan’s available reserve, plus (iii) the number of returning shares, if any, upon the cancellation or forfeiture of equity awards that are outstanding under the 2021 Plan. In addition, the number of shares of common stock reserved for issuance under the 2023 Plan will automatically increase on January 1 of each year, beginning on January 1, 2024, and continuing through and including January 1, 2033, by 5% of the total number of shares of common stock outstanding on December 31 of the immediately preceding calendar year, or a lesser number of shares determined by the Company’s Board of Directors prior to the applicable January 1. Upon adoption, the maximum number of shares of common stock that may be issued under the 2023 ESPP was initially 238,600 shares. The number of shares of common stock reserved for issuance under the 2023 ESPP will automatically increase on January 1 of each calendar year, beginning on January 1, 2024 and continuing through and including January 1, 2033, by the lesser of (i) 1% of the total number of shares of capital stock outstanding on December 31 of the preceding calendar year, (ii) 477,200 shares and (iii) a number of shares determined by the Company’s Board of Directors. Shares subject to purchase rights granted under the 2023 ESPP that terminate without having been exercised in full will not reduce the number of shares available for issuance under the 2023 ESPP.

On January 1, 2024, the number of shares of common stock reserved for issuance under the 2023 Plan and the 2023 ESPP automatically increased by 1,333,424 shares and 266,684 shares, respectively, to totals of 6,070,424 shares and 505,284 shares, respectively. On January 1, 2025, the number of shares of common stock reserved for issuance under the 2023 Plan and the 2023 ESPP automatically increased by 1,653,960 shares and 330,792 shares, respectively, to totals of 7,724,384 shares and 836,076 shares, respectively. As of December 31, 2024, 2,185,328 shares and 505,284 shares were available for future issuance under the 2023 Plan and 2023 ESPP, respectively. No shares have been issued under the 2023 ESPP through December 31, 2024.

Stock options granted under the 2021 Plan are issued from new shares upon exercise, have a contractual term of 10 years from grant date, and generally (i) are subject to requisite service requirements, (ii) vest over a four-year period with 25% of the options granted vesting after one year and the remainder vesting in equal monthly installments over the following 36 months, and (iii) allow for early exercise subject to repurchase. Stock options granted under the 2021 Plan to certain of the Company’s non-employees vest in equal monthly installments over a four-year period or vested upon the achievement of a certain milestone event. The Company repurchased a total of 3,827 shares of common stock issued pursuant to the early exercise of stock options granted under the 2021 Plan for a total of approximately $17,000 during the year ended December 31, 2024, which was recorded to treasury stock in the Company's balance sheet (see Note 8).

Stock options granted under the 2023 Plan through December 31, 2024 are issued from new shares upon exercise, have a contractual term of 10 years from grant date, and generally (i) are subject to requisite service requirements, and (ii) vest over a four-year period with 25% of the options granted vesting after one year and the remainder vesting in equal monthly installments over the following 36 months. Stock options granted under the 2023 Plan to certain of the Company's non-employee directors vest in equal annual installments over a three-year period or over a one-year period.

The following table summarizes the stock option activity under the 2021 Plan and the 2023 Plan for the years ended December 31, 2024 and December 31, 2023 (weighted-average remaining contractual term (in years) is not stated in thousands):


	Number of			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic
	Shares			(per share)		(in years)		Value
Outstanding as of December 31, 2023		2,415,740		$	8.32		7.83	$	13,689
Granted		1,520,330			15.60
Exercised		(135,646	)		3.62				1,288
Forfeited		(272,276	)		11.40
Expired		(70,230	)		12.94
Outstanding as of December 31, 2024		3,457,918		$	11.37		8.18	$	2,851
Options exercisable at December 31, 2024		1,954,937		$	8.16		7.38	$	2,851

The weighted average grant date fair value of options granted during the years ended December 31, 2024 and 2023 was $11.58 per share and $9.89 per share, respectively.

The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. The total intrinsic value of stock options exercised during the year ended December 31, 2023 was $0.

The total grant date fair values of stock options vested during the years ended December 31, 2024 and December 31, 2023 were $7.1 million and $2.4 million, respectively.

The Company estimated the fair value of options granted using a Black-Scholes option pricing model with the following assumptions presented on a weighted average basis during the year ended December 31, 2024 (not stated in thousands):


	Year Ended
	December 31,
	2024			2023
Risk-free interest rate		4.14	%		3.43	%
Expected term (in years)		6.02			5.78
Expected volatility		85.85	%		67.59	%
Expected dividend yield		0.00	%		0.00	%

The expected dividend yields are 0.00% as the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

As of December 31, 2024 there was $13.6 million of unrecognized stock-based compensation expense related to stock options estimated to be recognized over a weighted-average period of 2.62 years.

RSUs granted under the 2023 Plan through December 31, 2024 generally (i) are subject to requisite service requirements, and (ii) vest over a four-year period with 25% of the RSUs vesting after approximately one year and the remainder vesting in equal quarterly installments over the following 12 quarters.

The following table summarizes the RSU activity under the 2023 Plan for the year ended December 31, 2024:


	Number of			Weighted- Average Grant Date Fair Value
	Shares			(per share)
Unvested as of December 31, 2023		-		$	-
Granted		287,078			15.52
Vested		-			-
Forfeited		(20,778	)		14.65
Unvested as of December 31, 2024		266,300		$	15.59

As of December 31, 2024 there was $3.3 million of unrecognized stock-based compensation expense related to RSUs estimated to be recognized over a weighted-average period of 3.28 years.

Under the 2023 ESPP, eligible employees may purchase shares of the Company's common stock through payroll deductions at a price equal to 85% of the lower of the fair market values of the stock as of the beginning or the end of six-month offering periods. Employees may not purchase more than 6,000 shares of the Company's common stock during any offering period. As of and during the years ended December 31, 2024 and December 31, 2023, stock-based compensation expense and the fair value of unearned employee stock ownership plans related to the 2023 ESPP was not material.

Stock-based compensation expense was classified as follows in the Company’s statements of operations and comprehensive loss:


	Year Ended
	December 31,
	2024		2023
Research and development expense	$	6,001	$	1,751
General and administrative expense		6,473		1,292
Total stock-based compensation expense	$	12,474	$	3,043