v3.26.1
Stock-Based Compensation (Tables)
6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Share-Based Payment Arrangement [Abstract]    
Summary of the Fair Value of the Stock Options
The Company estimates the fair value of the stock options issued using the Black-Scholes option pricing model on the date of grant. The key assumptions used to apply this pricing model were as follows:
 
    
June 30,
 
    
2026
   
2025
 
Fair value of common stock
   $
 0.78-0.96
    $  0.78 – 1.13   
Risk-free interest rate
     3.94 %      4.26 % 
Expected dividend yield
     —        —   
Expected term (in years)
     5.9       6.0  
Expected volatility
     82.71 %      106.25 % 
The Company estimates the fair value of the stock options issued using the Black-Scholes option pricing model on the date of grant. The key assumptions used to apply this pricing model were as follows:
 
    
December 31,
 
    
  2025  
   
  2024  
 
Fair value of common stock
   $ 0.78 – 1.13     $ 1.01 – 1.13  
Risk-free interest rate
     3.94 %      4.25 % 
Expected dividend yield
     —        —   
Expected term (in years)
     6.1       6.1  
Expected volatility
     89.54 %      133.20 % 
Summary of the Option Activity
The following table summarizes option activity under the 2016 Plan for the six months ended June 30, 2026:
 
    
Number of
Options
    
Weighted-
Average
Exercise Price
Per Share
    
Weighted-
Average
Remaining
Contractual
Term (in years)
    
Aggregate
Intrinsic
Value (in
thousands)
 
Outstanding at December 31, 2025
     38,061,610      $ 0.77        6.9      $ 298  
Options granted
     5,353,691        0.79        
Options exercised
     (1,161,144 )       0.72        
Options forfeited
     (2,441,148 )       0.78        
Options expired
     (4,177,316 )       0.77        
  
 
 
    
 
 
    
 
 
    
 
 
 
Outstanding at June 30, 2026
     35,635,693      $ 0.78        7.4      $ 6,528  
  
 
 
    
 
 
    
 
 
    
 
 
 
Vested and exercisable at June 30, 2026
     21,465,199      $ 0.77        6.7      $ 4,045  
Unvested at June 30, 2026
     14,170,494      $ 0.78        8.2      $ 2,102  
The following table summarizes option activity under the 2016 Plan for the year ended December 31, 2025:
 
    
Number of
Options
    
Weighted-
Average
Exercise
Price
Per Share
    
Weighted-
Average
Remaining
Contractual
Term
(in years)
    
Aggregate
Intrinsic
Value
(in thousands)
 
Outstanding at December 31, 2024
     40,628,032      $ 1.03        8.4      $ 4,146  
Options granted
     432,000        0.78        
Options exercised
     (20,146 )       0.97        
Options forfeited
     (2,530,814 )       1.05        
Options expired
     (447,462 )       1.00        
  
 
 
    
 
 
    
 
 
    
 
 
 
Outstanding at December 31, 2025
     38,061,610      $ 0.77        6.9      $ 298  
  
 
 
    
 
 
    
 
 
    
 
 
 
Vested and exercisable at December 31, 2025
     23,056,967      $ 0.77        6.1      $ 298  
Unvested at December 31, 2025
     15,004,643      $ 0.78        8.2      $ —   
Summary of the Stock-Based Compensation Expense
The Company has recorded stock-based compensation expense as follows (in thousands):
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
Three Months Ended June 30,
 
  
Six Months Ended June 30,
 
 
  
2026
 
  
2025
 
  
2026
 
  
2025
 
Research and development
  
$
 688
 
  
$
 1,168
 
  
$
 1,368
 
  
$
 1,993
 
General and administrative
  
 
864
 
  
 
1,593
 
  
 
1,638
 
  
 
2,878
 
 
  
 
 
 
  
 
 
 
  
 
 
 
  
 
 
 
 
  
$1,552
 
  
$2,761
 
  
$3,006
 
  
$4,871
 
 
  
 
 
 
  
 
 
 
  
 
 
 
  
 
 
 
The Company has recorded stock-based compensation expense as follows (in thousands):
 
    
December 31,
 
    
2025
    
2024
 
Research and development
   $ 3,733      $ 2,938  
General and administrative
     5,198        4,122  
  
 
 
    
 
 
 
   $ 8,931      $ 7,060