Prepaid Expenses	12 Months Ended
Dec. 31, 2018
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid Expenses	5. Prepaid Expenses As of December 31, 2018, the amount of prepaid expenses was $4,805, consisting of $4,377 of prepaid R&D clinical costs, $245 of prepaid insurance and $183 of other costs. As of December 31, 2017, the amount of prepaid expenses was $1,635, consisting of $1,287 of prepaid R&D clinical costs, $124 of prepaid insurance and $224 of other costs.

Tabular disclosure of the amounts paid in advance for capitalized costs that will be expensed with the passage of time or the occurrence of a triggering event, and will be charged against earnings within one year or the normal operating cycle, if longer; the aggregate carrying amount of current assets, not separately presented elsewhere in the balance sheet; and other deferred costs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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