v3.25.2
Note 5 - Share-Based Compensation (Tables)
6 Months Ended
Jun. 30, 2025
Notes Tables  
Share-Based Payment Arrangement, Option, Activity [Table Text Block]
      

Weighted-

  

Weighted-

  

Aggregate

 
      

average

  

average

  

intrinsic

 
      

exercise

  

contractual

  

value

 
  

Amount

  

price

  

life (years)

  

(in thousands)

 

Outstanding at December 31, 2024

  4,385,477  $4.54   6.9  $1,307 

Granted

  292,489   1.60         

Canceled / forfeited

  (36,281)  85.80         

Outstanding at June 30, 2025

  4,641,685   3.72   6.7   121 

Options exercisable

  3,128,686   3.61   6.4   97 

Options vested and expected to vest

  4,618,336   3.71   6.7   121 
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
  

Six Months Ended

 
  

June 30,

 
  

2025

  

2024

 

Risk-free interest rate

  3.85%  4.07%

Expected volatility

  116.11%  116.86%

Expected term (in years)

  5.2   5.4 

Expected dividend yield

  %  %
Share-Based Payment Arrangement, Cost by Plan [Table Text Block]
  

Three Months Ended

  

Six Months Ended

 
  

June 30,

  

June 30,

 
  

2025

  

2024

  

2025

  

2024

 
  

(In thousands)

  

(In thousands)

 

Research and development

 $58  $110  $117  $219 

General and administrative

  479   462   905   913 

Total

 $537  $572  $1,022  $1,132