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	$ (235,503)	$ (46,759)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	744	781
Stock-based compensation	3,620	4,118
Acquired in-process research and development	130,486	0
Change in fair value of forward contract liability	58,170	0
Lease ROU asset and leasehold improvement impairment loss	2,580
Loss on disposal of long-lived assets	915
Amortization of operating lease assets	220	191
Purchase net premium on marketable securities		239
Net amortization of premium (accretion of discount) on marketable securities	(123)	(23)
Other	6	(7)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	3,368	(2,419)
Accounts payable	2,045	(1,352)
Deferred revenue	575	(914)
Development receivables	(1,271)	336
Operating lease liabilities	(298)	(250)
Accrued and other liabilities	189	(877)
Net cash used in operating activities	(34,277)	(46,936)
CASH FLOWS FROM INVESTING ACTIVITIES
Cash assumed from asset acquisition of Spyre	3,035
Purchases of property and equipment		(37)
Proceeds from sale of property and equipment	475
Purchases of marketable securities		(27,750)
Proceeds from maturities and sales of marketable securities	21,000	54,296
Net cash provided by investing activities	24,510	26,509
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from issuance of Series A non-voting convertible preferred stock, gross in connection with private placement	210,000
Proceeds from issuance of common stock and pre-funded warrants in registered direct offering, net of offering costs		42,979
Proceeds from employee stock plan purchases and stock option exercises	18	184
Principal payments on finance lease obligation	(16)	(347)
Net cash provided by financing activities	210,002	42,816
Effect of exchange rate on cash, cash equivalents, and restricted cash	24	(95)
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	200,259	22,294
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH
Beginning of period	36,416	16,980
End of period	236,675	$ 39,274
Supplemental Disclosure of Non-Cash Investing and Financing Information:
Unpaid direct transaction costs related to the asset acquisition of Spyre	2,067
Unpaid amounts related to issuance of Series A non-voting convertible preferred stock in connection with private placement	$ 12,677