Selected Balance Sheet Information - Schedule of prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Selected Balance Sheet Information
Prepaid manufacturing expense	$ 1,001	$ 0
Prepaid insurance	197	419
Prepaid consulting, subscriptions and other expenses	96	132
Other receivable	4	0
Prepaid conferences, travel	0	42
Total	$ 1,298	$ 593

n/a

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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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