Quarterly report pursuant to Section 13 or 15(d)

Consolidated Statements of Cash Flows

Consolidated Statements of Cash Flows - USD ($)
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Cash flows from operating activities    
Net income (loss) $ 11,587,015 $ (19,106,481)
Adjustments to reconcile net income (loss) to net cash used in operating activities:    
Depreciation 42,040 34,355
Stock-based compensation expense 323,774 437,681
Change in fair value of warrant liabilities (17,799,629) 12,274,559
Decrease in deferred rent   (7,759)
Net amortization of premium on marketable securities 45,643 100,994
Changes in operating assets and liabilities:    
(Increase) decrease in prepaid expenses and other current and non-current assets (1,070,468) 69,114
Decrease in accounts payable, accrued liabilities and other liabilities (453,101) (612,721)
Net cash used in operating activities (7,324,726) (6,810,258)
Cash flows from investing activities    
Purchases of marketable securities   (3,603,756)
Proceeds from sales of marketable securities 5,850,000 6,964,888
Purchases of property and equipment (19,999) (79,276)
Net cash provided by investing activities 5,830,001 3,281,856
Cash flows from financing activities    
Proceeds from exercise of warrants   3,875
Net cash provided by financing activities   3,875
Net decrease in cash and cash equivalents (1,494,725) (3,524,527)
Cash and cash equivalents at beginning of period 8,320,317 6,995,046
Cash and cash equivalents at end of period 6,825,592 $ 3,470,519
Supplemental disclosures of cash flow information:    
Right-of-use assets obtained in exchange for lease obligations 4,148,672  
Leasehold improvement obtained in exchange for lease incentive obligations $ 189,227