Stock-Based Compensation
Restricted Common Stock
A summary of the Company’s restricted common stock activity during the year ended December 31, 2025, is presented below:
Number of Restricted SharesWeighted-Average Per-Share  Grant-Date Fair Value
Unvested at December 31, 202475,958$0.78
Vested
(75,958)$0.78
Unvested at December 31, 2025$—
The Company did not issue shares of restricted common stock to founders and officers during the years ended December 31, 2025 or 2024. For the years ended December 31, 2025 and 2024, the liability related to the payments received for shares of unvested restricted common stock was de minimis. The aggregate fair value of restricted common stock awards that vested during the years ended December 31, 2025 and 2024, was $1.0 million and $1.3 million, respectively. The final vesting conditions for the restricted common stock awards were met in June 2025.
Stock Option Valuation
The weighted-average assumptions used to determine the fair values of stock options granted to employees and directors during the years ended December 31, 2025 and 2024, are presented as follows:
Year Ended December 31,
20252024
Expected term (in years)6.26.0
Volatility82.4%83.9%
Interest rate4.2%4.2%
Dividend yield
Stock Option Activity
The following table summarizes the Company’s common stock option activity for the year ended December 31, 2025:
Number of Shares
Weighted-Average Exercise Price
Weighted-Average Remaining Contractual Term
Aggregate Intrinsic Value
(in years)(in thousands)
Outstanding at December 31, 20243,700,335$5.87 8.3$16,522
Granted2,725,16019.03 
Exercised(599,191)6.07 
Cancelled or forfeited(58,505)10.97 
Outstanding at December 31, 20255,767,799$12.01 8.3$168,007
Exercisable at December 31, 20252,189,013$7.58 7.3$73,457
The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the estimated 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 weighted-average grant date fair value of options granted during the years ended December 31, 2025 and 2024, was $13.94 and $4.61, respectively. The total intrinsic value of options exercised in the years ended December 31, 2025 and 2024, was $14.7 million and $0.4 million, respectively.
Stock-Based Compensation Expense
During the years ended December 31, 2025 and 2024, the Company recorded stock-based compensation in the accompanying consolidated statements of operations and comprehensive loss as follows (in thousands):
Year Ended December 31,
20252024
Research and development expense$4,116 $1,500 
General and administrative expense7,950 2,208 
Total$12,066 $3,708 
As of December 31, 2025, there was $35.3 million of unrecognized stock-based compensation expense for common stock option awards that are expected to be recognized over a weighted-average period of 2.6 years. The stock-based compensation expense for restricted common stock awards was de minimis and fully recognized as of June 30, 2025, when the final vesting conditions were met.

About Stock Compensation Disclosures

Stock-based compensation disclosures detail the equity awards granted to employees and executives — including stock options, restricted stock units (RSUs), and performance shares — along with the valuation methods and assumptions used to expense them. This section reveals the true cost of talent retention and the alignment between management incentives and shareholder interests.

Key signals: total unrecognized compensation expense and its expected recognition period signal future earnings headwinds from already-granted awards. For stock options, examine Black-Scholes assumptions — expected volatility, risk-free rate, and expected term — as understating any of these reduces reported compensation expense. Compare stock compensation expense as a percentage of revenue against peers to assess dilution cost. Watch vesting schedules for acceleration clauses tied to change-of-control events. Performance-based awards with undemanding targets may indicate weak governance. Add back stock compensation to operating cash flow to calculate a more conservative free cash flow figure.