v3.26.1
Note 5 - Share-Based Compensation (Tables)
6 Months Ended
Jun. 30, 2026
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, 2025

  4,641,685  $3.72   6.2  $200 

Granted

  351,326   1.39         

Outstanding at June 30, 2026

  4,993,011   3.56   6.0    

Options exercisable

  3,767,547   3.58   5.8    

Options vested and expected to vest

  4,971,465   3.55   6.0    
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
  

Six Months Ended

 
  

June 30,

 
  

2026

  

2025

 

Risk-free interest rate

  4.13%  3.85%

Expected volatility

  106.21%  116.11%

Expected term (in years)

  5.2   5.2 

Expected dividend yield

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

Three Months Ended

  

Six Months Ended

 
  

June 30,

  

June 30,

 
  

2026

  

2025

  

2026

  

2025

 
  

(In thousands)

  

(In thousands)

 

Research and development

 $46  $58  $215  $117 

General and administrative

  177   479   640   905 

Total

 $223  $537  $855  $1,022