CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net loss	$ (22,797)	$ (46,934)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	513	516
Stock-based compensation expense	2,259	11,213
Loss on disposal of property and equipment	100
Payments received on net investment in lease	4	4
Changes in assets and liabilities:
Accounts receivable	(1,845)	(1,434)
Unbilled receivables	(209)	(1,027)
Inventory	(1,537)	(336)
Prepaid expenses and other current assets	946	(1,213)
Due from related parties	48	12
Prepaid inventory	281
Other long term assets	129	52
Accounts payable	666	(551)
Deferred grant funding	198	(1,058)
Deferred revenue	(134)	469
Due to related parties	45	(1,900)
Accrued expenses and other current liabilities	(1,817)	(2,013)
Net cash used in operating activities	(23,150)	(44,200)
Cash flows from investing activities:
Purchases of property and equipment	(283)	(254)
Net cash used in investing activities	(283)	(254)
Cash flows from financing activities:
Proceeds from exercise of stock options	107	2
Net cash provided by financing activities	107	2
Net decrease in cash and cash equivalents and restricted cash	(23,326)	(44,452)
Cash, cash equivalents and restricted cash, beginning of period	118,243	191,160
Cash, cash equivalents and restricted cash, end of period	94,917	146,708
Reconciliation of cash, cash equivalents, and restricted cash reported in the balance sheets
Cash and cash equivalents	93,948	145,104
Restricted cash	969	1,604
Total cash, cash equivalents and restricted cash	94,917	146,708
Supplemental disclosure of noncash information:
Noncash acquisition of fixed assets	$ 28
Write-off of notes receivable		$ 90