v3.19.3
Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)
 6 Months Ended 12 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Dec. 31, 2017
Cash flows from operating activities:        
Net loss $ (7,138,000) $ (2,946,000) $ (5,985,000) $ (11,561,000)
Adjustments to reconcile net loss to net cash used in operating activities:        
Depreciation expense 4,000 4,000 8,000 10,000
Stock-based compensation expense 168,000 150,000 309,000 301,000
Changes in fair value of warrant liability 95,000 1,000 98,000 (12,000)
Changes in fair value of derivative liability (60,000)    
Accretion of final charge upon maturity of Oxford Term Loan A and B 148,000 94,000 224,000 106,000
Amortization of issuance cost and discounts for term loans and convertible notes 16,000 130,000 40,000 54,000
Non-cash interest expense on convertible promissory notes 2,304,000 31,000 126,000  
Non-cash operating lease cost 140,000    
Changes in operating assets and liabilities:        
Prepaid expenses and other current assets (1,611,000) (12,000) 23,000 329,000
Other assets 57,000   1,000
Accounts payable 1,255,000 (607,000) (212,000) 601,000
Accrued liabilities 475,000 (312,000) (650,000) (12,000)
Lease liability (136,000)    
Net cash used in operating activities (4,223,000) (3,527,000) (6,019,000) (10,183,000)
Cash flows from investing activities:        
Purchases of property and equipment     (5,000) (3,000)
Net cash used in investing activities (5,000) (3,000)
Cash flows from financing activities:        
Payments on term loan (1,437,000) (616,000) (890,000) (139,000)
Proceeds from exercise of warrants       80,000
Proceeds from issuance of convertible promissory notes - related party 3,996,000 1,500,000 4,500,000  
Net cash provided by financing activities 2,559,000 884,000 3,610,000 (59,000)
Net decrease in cash, cash equivalents and restricted cash (1,664,000) (2,643,000) (2,414,000) (10,245,000)
Cash, cash equivalents and restricted cash at beginning of period 1,942,000 4,356,000 4,356,000 14,601,000
Cash, cash equivalents and restricted cash at end of period 278,000 1,713,000 1,942,000 4,356,000
Other supplemental disclosure:        
Cash paid for interest 173,000 190,000 $ 376,000 $ 355,000
Non-cash investing and financing activities:        
Right-of-use assets obtained in exchange for operating lease obligations(1) 227,000    
Reclassification of warrant liability to paid in capital 234,000    
Conversion of convertible preferred stock into common stock $ 34,015,000