CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net loss	$ (8,568)	$ (7,671)
Adjustment to reconcile net loss to net cash used in operating activities:
Non-cash stock-based compensation	291	311
Change in operating lease right of use assets	24	0
Change in fair value of common stock warrants	(19)	(1,153)
Change in fair value of contingent consideration	281	482
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(1,383)	(315)
Accounts payable	(1,476)	(263)
Accrued expenses and other current liabilities	638	(1,038)
Net cash used in operating activities	(10,212)	(9,647)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of offering costs	5,963	13,781
Collection of stock subscription receivable	308	0
Net proceeds from exercise of warrants	4	3,280
Net cash provided by financing activities	6,275	17,061
Net (decrease) increase in cash, cash equivalents, restricted cash, and restricted cash equivalents	(3,937)	7,414
Cash, cash equivalents, restricted cash, and restricted cash equivalents at the beginning of period	7,377	5,451
Cash, cash equivalents, restricted cash, and restricted cash equivalents at the end of period	3,440	12,865
Supplemental disclosure of cash flow information:
Cash received during the periods for interest	25	32
Supplemental disclosure of non-cash investing and financing activities:
Operating right of use asset and current and non-current lease liability	976	550
Impact of anti-dilution protection on liability-classified warrants	0	243
Offering expenses in accounts payable and accrued expenses and other current liabilities	$ 0	$ 365