Accrued Expenses and Other Current Liabilities - Schedule of Composition of Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Accrued clinical and related costs	$ 3,935	$ 819
Accrued compensation and related costs	1,162	1,746
Accrued interest	81	84
Operating lease liability, short-term	425	265
Accrued other	217	266
Accrued expenses and other current liabilities	$ 5,820	$ 3,180