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Stock-based Compensation (Tables)
12 Months Ended
Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]  
Summary of RSU activity
         
   Number
of Shares
   Weighted-
Average
Grant Date Fair Value
Per Share
 
Unvested units at December 31, 2022   47,335   $15.03 
Granted   43,500    5.24 
Vested   (23,414)   14.99 
Forfeited   (17,738)   9.88 
Unvested units at December 31, 2023   49,683   $8.32 
Schedule of assumptions
   December 31, 
   2023 
Risk-free interest rate   4.72% 
Expected volatility   113.74% 
Expected lives (in years)   5.25 
Expected dividend yield   0% 
Summary of stock option activity
                 
   Total Number
of Shares
   Weighted-
Average
Exercise
Price
Per Share
   Weighted-
Average
Remaining
Contractual
Term
   Aggregate
Intrinsic
Value
 
Balance at December 31, 2022   177   $35,231.40           
Granted   10,000    1.37           
Exercised                  
Forfeited                  
Expired   (93)   52,577.53           
Balance at December 31, 2023   10,084   $134.86    9.74 years   $ 
Exercisable at December 31, 2023   84   $16,026.76    2.78 years   $ 
Schedule of stock-based compensation expense
         
   December 31, 
   2023   2022 
Research and development  $132   $154 
General and administrative   171    260 
Total stock-based compensation  $303   $414