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CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Cash flows from operating activities: |  |  |
Net loss | $ (39,886) | $ (32,641) | $ (13,153)
Adjustments to reconcile net loss to net cash used in operating activities: |  |  |
Non-cash research and development expense |  | 4,595 | 3,517
Depreciation and amortization | 363 | 279 | 11
Change in fair value of derivative liabilities | (1,541) | (580) | (174)
Share-based compensation | 1,427 | 180 | 21
Unrealized foreign currency transaction loss | 83 |  |
Changes in operating assets and liabilities: |  |  |
Other receivables | (707) | (294) | (10)
Prepaid expenses and other current assets | (575) | (966) | (280)
Tax incentive receivables | (1,811) | (144) |
Deposits |  | (53) | (150)
Accounts payable | 2,349 | (644) | 671
Accrued expenses and other current liabilities | 1,315 | 2,322 | 409
Deferred rent | (128) | (84) |
Advance payments from collaborator |  | (929) | (470)
Net cash used in operating activities | (39,111) | (28,959) | (9,608)
Cash flows from investing activities: |  |  |
Purchases of property and equipment | (27) | (830) | (232)
Net cash used in investing activities | (27) | (830) | (232)
Cash flows from financing activities: |  |  |
Proceeds from initial public offering of common stock, net of commissions and underwriting discounts | 77,749 |  |
Payment of initial public offering costs | (3,574) |  |
Changes in restricted cash |  |  | (30)
Cash payment for non-controlling interests | (1,175) |  |
Net cash provided by financing activities | 116,111 | 34,413 | 15,275
Net increase in cash and cash equivalents | 76,973 | 4,624 | 5,435
Cash and cash equivalents at beginning of period | 10,315 | 5,691 | 256
Cash and cash equivalents at end of period | 87,288 | 10,315 | 5,691
Supplemental disclosure of non-cash investing and financing activities: |  |  |
Conversion of bridge units into preferred units | 8,500 |  | 8,000
Conversion of preferred stock to common stock | 107,018 |  |
Settlement of derivative liabilities upon issuance of preferred units | 944 |  | 888
Issuance of tranche rights with preferred units |  | 909 | 2,401
Deemed contribution of capital |  | 2,408 | 1,419
Settlement of derivative liability upon issuance of bridge units |  | 305 |
Issuance of contingent prepayment option with bridge units |  | 908 |
Cumulative dividends on redeemable convertible preferred shares | 6,146 | 3,441 | 932
Accretion of redeemable convertible preferred units and stock to redemption value | 632 | 969 | 34
Accretion of bridge units to redemption value | 576 | 27 | 2,307
Issuance of additional shares of common stock to minority investors under anti-dilution rights |  | 980 | 1,459
Purchases of property and equipment included in accounts payable, accrued expenses and deferred rent |  |  | 728
Deferred offering costs included in accounts payable and accrued expenses |  |  | 11
Series A Preferred Stock [Member] |  |  |
Cash flows from financing activities: |  |  |
Proceeds from issuance of preferred units, net of issuance costs |  |  | 7,330
Bridge Units [Member] |  |  |
Cash flows from financing activities: |  |  |
Proceeds from issuance of bridge units |  | 8,500 | 8,000
Series B Preferred Stock [Member] |  |  |
Cash flows from financing activities: |  |  |
Payment of initial public offering costs |  |  | $ (25)
Proceeds from issuance of preferred units, net of issuance costs |  | $ 25,913 |
Series C Preferred Stock [Member] |  |  |
Cash flows from financing activities: |  |  |
Payment of initial public offering costs | (176) |  |
Proceeds from issuance of preferred units, net of issuance costs | $ 43,111 |  |

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