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Accrued Expenses | 9 Months Ended
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Sep. 30, 2021
Payables and Accruals [Abstract] |
Accrued Expenses | ACCRUED EXPENSESAccrued expenses consisted of the following:
(in thousands) | September 30, 2021 |  | December 31, 2020
Accrued employee compensation and benefits | $ | 4,759 |  |  | 3,756 |
Accrued external research and development expenses | 2,977 |  |  | 3,150 |
Accrued professional fees | 899 |  |  | 627 |
Other | 439 |  |  | 485 |
| $ | 9,074 |  |  | $ | 8,018 |

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