CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (44,238)	$ (73,164)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	1,054	1,015
Stock-based compensation expense	4,741	10,652
Write-off of equipment	224
Other	25	91
Changes in assets and liabilities:
Accounts receivable	(1,086)	(1,550)
Unbilled receivables	(488)	(363)
Inventory	(2,209)	(312)
Prepaid expenses and other current assets	1,496	(1,837)
Due from related parties	48	(34)
Prepaid inventory	(412)	(281)
Other long term assets	(220)	(632)
Accounts payable	533	(1,570)
Deferred grant funding	(123)	(1,891)
Deferred revenue	(483)	1,664
Due to related parties	61	(1,981)
Accrued expenses and other current liabilities	(742)	(2,146)
Operating lease liabilities, net	10
Net cash used in operating activities	(41,809)	(72,339)
Cash flows from investing activities:
Purchases of property and equipment	(804)	(585)
Net cash used in investing activities	(804)	(585)
Cash flows from financing activities:
Proceeds from exercise of stock options	174	7
Net cash provided by financing activities	174	7
Net decrease in cash and cash equivalents and restricted cash	(42,439)	(72,917)
Cash, cash equivalents and restricted cash, beginning of year	118,243	191,160
Cash, cash equivalents and restricted cash, end of year	75,804	118,243
Reconciliation of cash, cash equivalents, and restricted cash reported in the balance sheets
Cash and cash equivalents	75,183	117,472
Restricted cash	621	771
Total cash, cash equivalents and restricted cash	75,804	118,243
Supplemental disclosure of cash flow information:
Cash received from exchange of research and development tax credits	519	131
Supplemental disclosure of noncash information:
Write-off of notes receivable		$ 90
Noncash acquisition of fixed assets	$ 3