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v3.20.1

Consolidated Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Cash flows from operating activities |  |  |
Net loss | $ (180,307) | $ (146,969) | $ (6,771)
Adjustments to reconcile net loss to net cash used in operating activities: |  |  |
Depreciation and amortization | 917 | 297 |
Stock-based compensation expense | 20,819 | 30,947 | 32
In process research and development expenses | 3,600 | 49,659 |
Amortization of operating lease right-of-use assets | 2,172 |  |
Amortization of long-term debt discount and issuance costs | 237 |  |
Amortization of premium on investments, net of accretion of discounts | (2,364) |  |
Net realized gain on investments | (28) |  |
Changes in operating assets and liabilities: |  |  |
Prepaid expenses and other current assets | (4,393) | (2,827) | (130)
Other assets | 2,714 | (584) |
Operating lease liabilities | (2,108) |  |
Accounts payable | (1,399) | 2,085 | 57
Accrued expenses | 1,521 | 5,938 | 824
Accrued research and development expenses | 8,605 | 10,527 | 126
Accrued compensation and benefits | 5,180 |  |
Accrued interest expense |  | (117) | 117
Net cash used in operating activities | (144,834) | (51,044) | (5,745)
Cash flows from investing activities |  |  |
Research and development asset acquisitions, net of cash acquired | (3,600) | (17,721) |
Purchase of marketable securities | (499,079) | (123,500) |
Maturities of marketable securities | 328,000 |  |
Sales of marketable securities | 30,501 |  |
Purchase of property and equipment | (2,966) | (3,490) |
Net cash used in investing activities | (147,144) | (144,711) |
Cash flows from financing activities |  |  |
Proceeds from issuance of convertible note |  |  | 6,000
Proceeds from issuance of common stock in a public offering, net | 291,311 |  |
Proceeds from the issuance of long-term debt, net of debt discount and issuance costs of $1,778 | 28,222 |  |
Proceeds from the exercise of stock options | 2,045 |  |
Repayment of notes payable to related parties |  | (40) |
Payment of deferred offering costs |  | (2,144) |
Net cash provided by financing activities | 321,578 | 300,859 | 6,000
Effect of exchange rate changes on cash, cash equivalents and restricted cash | 70 |  |
Net increase in cash, cash equivalents and restricted cash | 29,600 | 105,104 | 255
Cash, cash equivalents and restricted cash, at the beginning of the period | 105,419 | 315 | 60
Cash, cash equivalents and restricted cash, at the end of the period | 135,089 | 105,419 | $ 315
Supplemental disclosure of cash flow information: |  |  |
Cash paid for interest | 1,475 | 119 |
Supplemental disclosure of noncash investing and financing activities: |  |  |
Acquisition of in-process research and development through issuance of stock |  | 19,284 |
Issuance of Series A convertible preferred stock to convert debt and accrued interest |  | 6,124 |
Unpaid deferred offering costs - net |  | 1,545 |
Right-of-use assets obtained in exchange for lease liabilities | 12,458 |  |
Conversion of convertible preferred stock to common stock | 338,367 |  |
Change in unrealized gain on marketable securities, net of tax | 331 | (61) |
Unpaid property and equipment | $ 183 |  |
Series A Convertible Preferred Stock |  |  |
Cash flows from financing activities |  |  |
Proceeds from issuance of convertible preferred stock, net |  | 73,491 |
Series B Convertible Preferred Stock |  |  |
Cash flows from financing activities |  |  |
Proceeds from issuance of convertible preferred stock, net |  | $ 229,552 |

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- Definition The cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585 + Details
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