Prepaid Expenses	6 Months Ended
Jun. 30, 2019
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid Expenses	7. Prepaid expenses As of June 30, 2019, prepaid expenses were $7,512, consisting of $6,461 of prepaid R&D clinical costs, $671 of prepaid insurance and $380 of other prepaid costs. As of December 31, 2018, prepaid expenses were $4,805, consisting of $4,377 of prepaid R&D clinical costs, $245 of prepaid insurance, and $183 of other prepaid costs.

The entire disclosure for prepaid expenses, which are the amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

No definition available.

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