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Consolidated Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES: |  |  |
Net income (loss) | $ (209,360) | $ (149,338) | $ 24,926
Adjustments to reconcile net loss to net cash provided (used in) operating activities: |  |  |
Depreciation | 12 | 33 | 43
(Accretion) amortization of investments | (14,803) | (3,382) | 644
Non-cash operating lease expense | 739 | 421 | 413
Non-cash interest income (expense) | 0 | 1,103 | (225)
Changes in fair value of derivative liability | 0 | (187) | (389)
Stock-based compensation | 30,951 | 16,019 | 13,317
Other | 0 | 0 | (1)
Changes in operating assets and liabilities: |  |  |
Prepaid expenses and other assets | 676 | (2,972) | (1,394)
Collaboration receivable, net | 10,706 | (3,474) | 0
Accounts payable | 5,611 | (1,319) | 2,161
Deferred revenue | 0 | 0 | (13,133)
Accrued expenses and other liabilities | 14,867 | 9,421 | 2,769
Net cash (used in) provided by operating activities | (160,601) | (133,675) | 29,131
CASH FLOWS FROM INVESTING ACTIVITIES: |  |  |
Purchases of property and equipment | 0 | 0 | (129)
Proceeds from sales of equipment | 0 | 225 | 0
Purchases of short and long-term investments | (354,606) | (495,346) | (294,719)
Proceeds from sales and maturities of short-term investments | 472,215 | 308,933 | 253,975
Net cash provided by (used in) investing activities | 117,609 | (186,188) | (40,873)
CASH FLOWS FROM FINANCING ACTIVITIES: |  |  |
Payment on term loan | 0 | (20,996) | 0
Proceeds from ESPP | 910 | 401 | 367
Proceeds from stock option exercises | 5,128 | 11,459 | 6,336
Net cash provided by financing activities | 264,132 | 172,254 | 118,464
NET (DECREASE) INCREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH | 221,140 | (147,609) | 106,722
CASH, CASH EQUIVALENTS AND RESTRICTED CASH—beginning of year | 74,471 | 222,080 | 115,358
CASH, CASH EQUIVALENTS AND RESTRICTED CASH—end of year | 295,611 | 74,471 | 222,080
Cash and cash equivalents | 295,394 | 74,356 | 221,965
Restricted cash | 217 | 115 | 115
Incyte Share Purchase Agreement [Member] |  |  |
CASH FLOWS FROM FINANCING ACTIVITIES: |  |  |
Proceeds from issuance of common stock in follow-on public stock offering, net | 0 | 0 | 24,848
Follow-on Public Offerings [Member] |  |  |
CASH FLOWS FROM FINANCING ACTIVITIES: |  |  |
Proceeds from issuance of common stock in follow-on public stock offering, net | 215,955 | 161,965 | 81,206
At-the-Market Offering [Member] |  |  |
CASH FLOWS FROM FINANCING ACTIVITIES: |  |  |
Proceeds from issuance of common stock in follow-on public stock offering, net | 42,139 | 19,425 | 5,131
Derivative Liability [Member] | Incyte Share Purchase Agreement [Member] |  |  |
CASH FLOWS FROM FINANCING ACTIVITIES: |  |  |
Proceeds from issuance of common stock in follow-on public stock offering, net | $ 0 | $ 0 | $ 576

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