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CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2017
Cash flows from operating activities: |  |  |  |
Net loss | $ (3,150) | $ (4,409) | $ (12,634) | $ (22,686)
Adjustments to reconcile net loss to net cash used in operating activities: |  |  |  |
Depreciation and amortization | 443 | 497 | 2,004 | 2,151
Amortization of deferred financing costs and debt discount | 168 | 105 | 578 | 707
In process research and development acquired from Azaya Therapeutics |  |  | 0 | 1,686
Change in fair value of warrants | (210) | 0 | (2,233) | 0
Allocation of issuance cost associated with warrants |  |  | 470 | 0
Provision for doubtful accounts |  |  | 18 | 0
Provision for excess inventory | 0 | 326 | 463 | 340
Share-based compensation expense | 49 | 143 | 355 | 753
Loss (gain) on asset disposal | 0 | 22 | 36 | (42)
Increases (decreases) in cash caused by changes in operating assets and liabilities: |  |  |  |
Accounts receivable | (212) | (747) | (173) | 1,129
Inventories | 16 | 141 | 475 | 251
Other current assets | 16 | 301 | 85 | (593)
Other assets | 1 | (24) | 23 | (94)
Accounts payable and accrued expenses | (405) | (556) | (1,532) | (1,817)
Deferred revenues | (25) | 84 | 73 | (3)
Long-term deferred rent and other |  |  | 17 | 90
Other long-term liabilities | 39 | (2) |  |
Net cash used in operating activities | (3,270) | (4,119) | (11,975) | (18,128)
Cash flows from investing activities: |  |  |  |
Purchases of property and equipment /long-lived assets | (6) | (53) |  |
Proceeds from sale of assets |  |  | 0 | 113
Net cash used in investing activities | (6) | (53) | (133) | (1,383)
Cash flows from financing activities: |  |  |  |
Principal payments on long-term obligations |  |  | 0 | (4,720)
Financed capital expenditures |  |  | (66) | 0
Proceeds from sale of common stock, net | 1,919 | (150) | 0 | 0
Proceeds from sale of common and preferred stock |  |  | 8,766 | 23,613
Costs from sale of common and preferred stock |  |  | (1,532) | (2,078)
Net cash provided by financing activities | 1,891 | (150) | 7,168 | 16,815
Payment of financing lease liability | (28) |  |  |
Effect of exchange rate changes on cash and cash equivalents | (4) | 39 | 16 | 11
Net decrease in cash and cash equivalents | (1,389) | (4,283) | (4,924) | (2,685)
Cash, cash equivalents, and restricted cash at beginning of period | 5,301 | 10,225 | 10,225 | 12,910
Cash, cash equivalents, and restricted cash at end of period | 3,912 | 5,942 | 5,301 | 10,225
Cash paid during period for: |  |  |  |
Interest | 347 | 311 | 1,331 | 1,364
Supplemental schedule of non-cash investing and financing activities: |  |  |  |
Conversion of preferred stock into common stock | $ 0 | $ 4 | 8 | 23
Fair value of Series C and Series B Convertible Preferred Stock beneficial conversion feature |  |  | 2,487 | 3,977
Property Plant And Equipment Excluding Research Lab Equipment And Leasehold Improvements [Member] |  |  |  |
Cash flows from investing activities: |  |  |  |
Purchases of property and equipment /long-lived assets |  |  | (133) | (295)
Assets Purchased from Azaya Therapeutics, Inc. [Member] |  |  |  |
Cash flows from investing activities: |  |  |  |
Purchases of property and equipment /long-lived assets |  |  | 0 | (1,201)
Supplemental schedule of non-cash investing and financing activities: |  |  |  |
Common stock issued in payment for the assets acquired |  |  | $ 0 | $ 2,311

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- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585 + Details
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- Definition The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1377-109256 + Details
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- Definition The cash inflow from the additional capital contribution to the entity. + 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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- Definition The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity. + 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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- Definition The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(5)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
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- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585 + Details
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- Definition The amount of the write-off for research and development assets that were acquired in a transaction other than a business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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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=118932676&loc=d3e3602-108585 + Details
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