Selected Balance Sheet Information - Schedule of prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Selected Balance Sheet Information
Prepaid clinical research organizations	$ 477	$ 48
Prepaid insurances	378	549
Prepaid consulting, subscriptions and other expenses	135	134
Prepaid Manufacturing expenses	94	622
Prepaid conferences, travel	0	25
Other receivables	0	3
Total	$ 1,084	$ 1,381

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Sum of the amount paid in advance for clinical research organization.

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Sum of the amount paid in advance for consulting, subscriptions and other expenses.

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Amount of Prepaid Manufacturing Expense.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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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.

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