Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Operating activities
Net loss	$ (34,482)	$ (23,016)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	7,480	2,922
Depreciation and amortization	3,081	4,740
Non-cash lease expense	226	172
Loss on disposal of property and equipment	1	29
Loss on extinguishment of debt	997	53
Non-cash interest (income) expense	222	155
Changes in operating assets and liabilities:
Accounts receivable, net	(146)	(3,050)
Prepaid expenses and other current assets	(810)	377
Other non-current assets	4	77
Accounts payable	(203)	(6,451)
Accrued expenses and other current liabilities	215	(227)
Refund liability	0	(1,769)
Operating lease liabilities	(570)	(488)
Net cash used in operating activities	(23,985)	(26,476)
Investing activities
Purchases of property, plant and equipment	(101)	(87)
Proceeds from the sale of property, plant and equipment	5	0
Net cash used in investing activities	(96)	(87)
Financing activities
Principal payments on finance leases	(235)	(387)
Principal payments on long-term debt	(10,500)	(10,353)
Proceeds from issuance of long-term debt with warrants, net	19,767	10,410
Receipts from litigation financing	421	3,920
Proceeds from sale of common stock, net of underwriting fees and commissions	54,461	21,710
Proceeds from issuance of common stock under stock incentive plans	993	1
Net cash provided by financing activities	64,907	25,301
Net increase (decrease) in cash and cash equivalents	40,826	(1,262)
Cash and cash equivalents, beginning of period	57,494	65,316
Cash and cash equivalents, end of period	98,320	64,054
Supplemental disclosure of cash flow information
Cash paid for interest	1,105	309
Cash paid for operating lease liabilities	928	901
Reduction of lease liability and right-of-use asset from lease modification	0	39
Non-cash increase in indemnification asset through accounts payable	$ 273	$ 4,326