XML 44 R32.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Note 11 - Benefit Plans (Tables)
3 Months Ended
Mar. 31, 2024
Notes Tables  
Share-Based Payment Arrangement, Cost by Plan [Table Text Block]
   

Three Months Ended March 31,

 

(in thousands)

 

2024

   

2023

 

General and administrative

  $ 1,136     $ 1,250  

Research and development

    877       973  

Total stock-based compensation expense

  $ 2,013     $ 2,223  
   

Three Months Ended March 31,

 

(in thousands)

 

2024

   

2023

 

Stock options

  $ 2,002     $ 2,222  

Stock awards

    11       1  

Total stock-based compensation expense

  $ 2,013     $ 2,223  
Share-Based Payment Arrangement, Option, Activity [Table Text Block]

(in thousands, except share, per share, and term data)

 

Number of Options

    Weighted Average Exercise Price Per Share     Weighted Average Remaining Term (Years)    

Intrinsic Value

 

Outstanding – December 31, 2023

    21,846,388     $ 2.26       7.28     $ 302  

Granted

    280,070       0.44       9.95        

Forfeited

    (141,124 )     5.33              

Outstanding – March 31, 2024

    21,985,334     $ 2.22       7.07     $ 568  

Vested and exercisable – March 31, 2024

    12,511,524     $ 2.55       5.79     $ 567  

Vested, exercisable or expected to vest – March 31, 2024

    21,985,334     $ 2.22       7.07     $ 568  
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
  

Three Months Ended March 31,

 
  

2024

  

2023

 

Expected stock price volatility

  99.99%  96.22% –103.24%

Risk-free interest rate

  4.04%  3.38% –3.98%

Expected dividend yield

  0.00%  0.00%

Expected term of options (in years)

  5.00   5.00 –6.08 
Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]
    Number of Stock Awards     Weighted Average Grant Date Fair Value  

Unvested balance – December 31, 2023

    778,815     $ 9.72  

Converted to shares of Common Stock upon vesting

    (10,870 )     1.15  

Unvested balance – March 31, 2024

    767,945     $ 9.84