CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020
Operating activities:
Net loss		$ (33,279)	$ (30,352)	[1]
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization		41	47
Equity-based compensation expense		12,230
Amortization or accretion on marketable securities		1,973	146
License expense in exchange for subsidiary common stock		67	1,019
Acquired in-process research and development assets			6,447
Changes in operating assets and liabilities:
Prepaid expenses and other current assets		(5,104)	(526)
Other assets			48
Accounts payable		(5,980)	1,064
Accrued expenses and other current liabilities		1,790	1,771
Net cash used in operating activities		(28,262)	(20,336)
Investing activities:
Purchases of property and equipment			(11)
Net cash acquired upon consolidation of Mica			1,450
Purchase of marketable securities		(448,551)	(48,264)
Proceeds from sales and maturities of marketable securities		130,638	29,965
Net cash used in investing activities		(317,913)	(16,860)
Financing activities:
Proceeds from issuance of common stock equivalents	[2]		14,250
Proceeds from initial public offering		267,268
Payment of issuance costs related to common stock equivalents	[2]		(213)
Payment of deferred offering costs		(2,688)
Proceeds from issuance of noncontrolling interests		923	1,206
Proceeds from exercise of stock options		579
Net cash provided by financing activities		266,082	15,243
Net decrease in cash and cash equivalents		(80,093)	(21,953)
Cash and cash equivalents at beginning of period		168,198	63,250
Cash and cash equivalents at end of period		88,105	$ 41,297
Noncash financing activities
Deferred offering costs paid in the prior year		$ 65

[1] The shares and per share amounts for the nine months ended September 30, 2020 were derived from the unaudited consolidated financial statements as of that date and were retroactively adjusted as a result of the Reorganization and Reverse Stock Split. See Note 3 to the unaudited consolidated financial statements for additional details.

[2] Changes in equity activities for the nine months ended September 30, 2020 were retroactively adjusted, including shares and per share amounts, as a result of the Reorganization and Reverse Stock Split. See Note 3 to the unaudited consolidated financial statements for additional details.