Selected Balance Sheet Information (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Other Current Assets [Line Items]
Clinical consulting services refund receivable	$ 612	$ 0
Prepaid conferences, travel and other expenses	406	295
Grant receivable	130	185
Prepaid insurances	69	358
Prepaid clinical research organizations	46	1,677
Total	$ 1,263	$ 2,515

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

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Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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