v3.25.4

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2025

Stock-Based Compensation

Summary of stock option activity

A summary of stock option activity for awards under the Plans is presented below:

​	​	​	​	​	​	​	​	​	​	​
​	​	Options Outstanding and Exercisable
​	​	​	​	​	​	​	Weighted	​	​	​
​	​	​	​	Weighted		​	Average	​	Aggregate
​	​	​	​	Average		​	Remaining	​	Intrinsic
​	​	Number of	​	Exercise		​	Contractual	​	Value(1)
​	​ ​ ​	Shares	​ ​ ​	Price		​ ​ ​	Life (Years)	​ ​ ​	(in thousands)
Outstanding as of January 1, 2024	​	567,995	​	$	105.96	​	7.3	​	$	52
Granted		248,609	​	$	19.80		—	​		—
Exercised	​	(1,214)	​	$	18.60	​	—	​	​	—
Forfeitures	​	(77,495)	​	$	41.76	​	—	​	​	—
Outstanding as of December 31, 2024		737,895	​	$	83.84		7.1	​	$	22
Granted	​	120,748	​	$	9.33	​	—	​	​	—
Exercised	​	—	​	$	—	​	—	​	​	—
Forfeitures	​	(9,677)	​	$	37.74	​	—	​	​	—
Outstanding as of December 31, 2025	​	848,966	​	$	73.76	​	6.5	​	​	—
Exercisable as of December 31, 2025		636,486	​	$	94.11		5.8	​	$	55

(1) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the fair value of the common stock for the options that were in the money at December 31, 2025 and 2024.

Summary of stock based compensation expense recorded

​	​	​	​	​	​	​
​	​	December 31,
​	​	​	​	​	​	​
(in thousands)	​	2025		​ ​ ​	2024
Research and development	​	$	1,345	​	$	2,756
General and administrative	​		1,641	​		3,579
Total stock-based compensation expense	​	$	2,986	​	$	6,335

Summary of assumptions used in the Black Scholes option pricing model for stock options granted

The assumptions used in the Black-Scholes option-pricing model for stock options granted were as follows:

​

​	​	​	​	​	​	​	​
​	​	Year Ended					​
​	​	December 31,					​
​	​ ​ ​	2025		​ ​ ​	2024		​
Expected term		6.0	years	​	5.8	years	​
Expected volatility		90.5	%	​	83.3	%	​
Risk free interest rate		4.4	%	​	3.6 - 4.7	%	​
Expected dividend yield		—	%	​	—	%	​

​

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