Accrued Expenses and Other Current Liabilities
 12 Months Ended
Dec. 31, 2021
Accrued Expenses And Other Current Liabilities [Abstract]  
Accrued Expenses and Other Current Liabilities

6. Accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):

 

 

 

December 31,

 

 

 

2021

 

 

2020

 

Accrued external research and development

 

$

4,031

 

 

$

3,136

 

Accrued payroll and benefits

 

 

2,603

 

 

 

1,500

 

Accrued professional fees

 

 

233

 

 

 

691

 

Accrued interest

 

 

17

 

 

 

437

 

Accrued other

 

 

—

 

 

 

46

 

 

 

$

6,884

 

 

$

5,810