Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Prepaid insurance	$ 175	$ 328
Other prepaid expenses	618	334
Deposits and other current assets	138	125
Total prepaid expenses and other current assets	1,658	837
Surface Pharmaceuticals Inc [Member]
Receivable due from related party	50	50
Melt Pharmaceuticals, Inc. [Member]
Receivable due from related party	$ 677

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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Amount of current assets classified as other.

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Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal 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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Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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