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CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2021 | Sep. 30, 2020
Cash flows from operating activities: |  |
Net loss | $ (58,489) | $ (43,731)
Adjustments to reconcile net loss to net cash used in operating activities: |  |
Stock-based compensation expense | 4,571 | 4,030
Depreciation and amortization expense | 367 | 248
Non-cash lease expense | 1,031 | 588
Accretion of debt discount | 557 | 389
Loss on extinguishment of debt | 0 | 162
Other | 283 | (219)
Changes in operating assets and liabilities: |  |
Prepaid expenses, other current assets and research and development incentive receivable | (14) | (2,420)
Accounts payable | (695) | 121
Accrued expenses | 1,069 | 1,722
Lease liabilities | (473) | (904)
Operating lease right-of-use asset, net of non-cash portion | 59 | 1,300
Net cash used in operating activities | (51,852) | (41,314)
Cash flows from investing activities: |  |
Acquisition of property, equipment and intangible assets | (602) | (1,060)
Net cash used in investing activities | (602) | (1,060)
Cash flows from financing activities: |  |
Proceeds from exercise of stock options and pre-funded warrants and issuance of shares of common stock under employee stock purchase plan | 157 | 468
Employee taxes paid related to net share settlement of vested restricted stock units | 0 | (278)
Proceeds from borrowings under loan and security agreements, net of issuance costs | 0 | 4,888
Proceeds from sale of shares of common stock, redeemable common stock and pre-funded warrants, net of issuance costs | 51,518 | (313)
Settlement and retirement of redeemable common stock | (2,000) | 0
Net cash provided by financing activities | 49,675 | 4,765
Effect of exchange rate changes on cash, cash equivalents and restricted cash | (203) | 240
Net decrease in cash, cash equivalents and restricted cash | (2,982) | (37,369)
Cash, cash equivalents and restricted cash at beginning of period | 80,702 | 128,086
Cash, cash equivalents and restricted cash at end of period | 77,720 | 90,717
Supplemental disclosure of non-cash investing and financing activities: |  |
Acquisition of property, equipment and right-of-use assets included in accounts payable and accrued expenses | 0 | 2,052
Acquisition of right-of-use asset financed by lease liabilities | 1,343 | 4,646
Issuance costs not yet paid related to sale of shares of common stock, redeemable common stock and pre-funded warrants | $ 0 | $ 178

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- Definition Amount of noncash expense for share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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- Definition Increase decrease in lease liabilities. + References No definition available. + Details
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- Definition Increase (Decrease) In Operating Lease, Right-Of-Use Asset, Net Of Non-cash Potion + References No definition available. + Details
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- Definition Non-cash interest expense. + References No definition available. + Details
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- Definition Non-cash lease expense. + References No definition available. + Details
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- Definition Proceeds from exercise of stock options and warrants. + References No definition available. + Details
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