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Accrued Expenses | 3 Months Ended
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Mar. 31, 2019
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Accrued Expenses |
6. | Accrued Expenses
Accrued expenses consisted of the following:
|  | March 31, 2019 |  |  | December 31, 2018 |
Accrued employee compensation and benefits |  | $ | 1,239 |  |  |  | 924 |
Accrued external research and development expenses |  |  | 819 |  |  |  | 754 |
Accrued professional fees |  |  | 1,850 |  |  |  | 1,324 |
Deferred rent, current portion |  |  | — |  |  |  | 93 |
Other |  |  | 271 |  |  |  | 156 |
|  | $ | 4,179 |  |  | $ | 3,251 |

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