Selected Balance Sheet Information - Schedule of prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Selected Balance Sheet Information
Prepaid manufacturing expenses	$ 622	$ 0
Prepaid insurance	549	419
Prepaid consulting, subscriptions and other expenses	134	132
Prepaid clinical research organizations	48	0
Prepaid conferences, travel	25	42
Other receivable	3	0
Total	$ 1,381	$ 593

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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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