Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net loss	$ (12,449)	$ (19,942)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	984	979
Non-cash lease expense	142	151
Stock-based compensation expense	1,215	1,952
Change in fair value of stock warrants	(29)	(257)
Change in fair value of contingent consideration	(242)	2,047
Other non-cash reconciling items	(1)
Change in operating assets and liabilities:
Prepaid expenses, other current assets and other assets	334	83
Other Assets		(40)
Accounts payable	(848)	(153)
Accrued compensation	204	(353)
Accrued clinical trial site costs	(264)	138
Operating lease liabilities	(120)	(168)
Other liabilities	92	62
Net cash used in operating activities	(10,982)	(15,501)
Cash flows from investing activities:
Purchases of property and equipment	(7)	(4)
Net cash used in investing activities	(7)	(4)
Cash flows from financing activities:
Proceeds from sale of common stock and pre-funded warrants, net of costs	13,766
Tax withholding payments for net share-settled equity awards	(16)	(120)
Principal paid on finance lease liabilities		(3)
Net cash provided by (used in) financing activities	13,750	(123)
Net increase (decrease) in cash and cash equivalents	2,761	(15,628)
Cash and cash equivalents, beginning of period	21,304	49,224
Cash and cash equivalents, end of period	$ 24,065	33,596
Supplemental disclosure of non-cash activities
Right-of-use assets obtained in exchange for operating lease obligations		581
Deferred financing costs included in accounts payable		$ 12