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Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands | 6 Months Ended
--- | ---
Jun. 30, 2024 | Jun. 30, 2023
Operating Activities: |  |
Net loss | $ (41,383) | $ (37,254)
Adjustments to reconcile net loss to net cash used in operating activities: |  |
Non-cash lease expense | 2,313 | 1,317
Stock-based compensation expense | 1,832 | 750
Depreciation expense | 1,447 | 1,726
Net amortization of premiums and discounts on marketable securities | (171) | (79)
Changes in operating assets and liabilities: |  |
Prepaid expenses and other current assets | (1,392) | (99)
Accounts payable | (507) | 347
Accrued expenses and other current liabilities | (4,049) | (221)
Operating lease liabilities | 5,254 | (904)
Other non-current assets | 172 | 13
Net cash used in operating activities | (36,484) | (34,404)
Investing Activities: |  |
Purchases of marketable securities | (96,432) | 0
Proceeds from maturities of marketable securities | 0 | 18,000
Purchases of property and equipment | (11,572) | (5,935)
Net cash (used in) provided by investing activities | (108,004) | 12,065
Financing Activities: |  |
Proceeds from PIPE financing, net of issuance costs | 67,384 | 0
Proceeds from exercises of stock options | 311 | 133
Other financing activities, net | 0 | (226)
Net cash provided by financing activities | 67,695 | 45,365
Net (decrease) increase in cash, cash equivalents and restricted cash | (76,793) | 23,026
Cash, cash equivalents and restricted cash, beginning of period | 173,119 | 41,477
Cash, cash equivalents and restricted cash, end of period | 96,326 | 64,503
Non-cash investing and financing activities: |  |
Purchases of property and equipment in accounts payable and accrued expenses | 914 | 101
Financing costs in accounts payable and accrued expenses | 48 | 815
Operating lease liabilities arising from right-of-use assets | 0 | 26,777
Supplemental cash flow information: |  |
Cash paid for income taxes | 47 | 27
Cash paid for operating lease liabilities | 1,624 | 1,491
Series B-2 Preferred Stock [Member] |  |
Financing Activities: |  |
Proceeds from Series B-2 convertible preferred stock, net of issuance costs | $ 0 | $ 45,458

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