Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net loss	$ (10,466)	$ (8,341)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation of property and equipment	500	557
Redeemable warrants valuation adjustment	120	(1,485)
Fair value of convertible note adjustment		(12)
Change in convertible debt - refinancing		20
Extinguishment of notes payable	142	345
Warrant modification	46
Amortization of patent, trademark rights	41	53
Changes in ROU assets	(36)	26
Equity-based compensation	596	649
Realized (loss) gain on sale of marketable securities	(12)
Amortization of finance and debt issuance costs	77	303
Change in assets and liabilities:
Accounts receivable and other receivables	794	1,032
Prepaid expenses and other current assets	764	49
Lease liability	36	(25)
Accounts payable	(265)	24
Accrued interest expense	230
Accrued expenses	(81)	27
Net cash used in operating activities	(7,514)	(6,778)
Cash flows from investing activities:
Proceeds from sale of marketable securities	8,497
Purchase of marketable securities	(17,169)	(588)
Purchase of property and equipment	(13)	(68)
Purchase of patent and trademark rights	(297)	(202)
Net cash used in investing activities	(8,982)	(858)
Cash flows from financing activities:
Payment of note payable	(4,279)
Financing obligation payments	(265)	(254)
Proceeds from note payable, net of issuance costs		1,900
Proceeds from sale of stock, net of issuance costs	58,066	15,307
Net cash provided by financing activities	53,522	16,953
Net increase in cash and cash equivalents	37,026	9,317
Cash and cash equivalents at beginning of period	1,470	299
Cash and cash equivalents at end of period	38,496	9,616
Supplemental disclosures of non-cash investing and financing cash flow information:
Unrealized loss on marketable securities	(12)
Conversion of Series B preferred	45	4,529
Conversion of note payable into shares		1,474
Stock issued to settle accounts payable	20	84
Operating lease - right of use assets	$ 65	$ 188