Selected Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Other Current Assets [Line Items]
Prepaid manufacturing expenses	$ 415	$ 0
Prepaid insurances	287	419
Prepaid consulting, subscriptions and other expenses	127	132
Prepaid clinical research organizations	22	0
Prepaid conferences, travel	3	42
Other receivables	6	0
Total	$ 860	$ 593

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

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