SELLAS Life Sciences (SLS) 10-Q 14 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Nov. 09, 2018
Document Document And Entity Information [Abstract]
Entity Registrant Name	SELLAS Life Sciences Group, Inc.
Trading Symbol	SLS
Entity Central Index Key	1,390,478
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Common Stock, Shares Outstanding		22,026,476

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 9,968	$ 2,319
Restricted cash and cash equivalents	114	10,431
Other receivable	6,600	0
Litigation settlement insurance recovery	474	0
Prepaid expenses and other current assets	651	337
Total current assets	17,807	13,087
In-process research and development	17,600	17,600
Goodwill	1,914	1,914
Deposits and other assets	1,149	925
Total assets	38,470	33,526
Current liabilities:
Current portion of long-term debt	76	8,377
Accounts payable	7,238	11,691
Accrued expenses and other current liabilities	4,683	3,201
Litigation settlement payable	0	1,300
Total current liabilities	11,997	24,569
Deferred tax liability	1,722	1,673
Warrant liability	975	1,309
Contingent consideration	5,319	1,294
Long-term debt, net of current portion	0	2,611
Total liabilities	20,013	31,456
Commitments and contingencies (Note 8)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 5,000,000 shares authorized; Series A convertible preferred stock, 17,500 shares designated; no shares issued and outstanding at September 30, 2018 and December 31, 2017	0	0
Common stock, $0.0001 par value; 350,000,000 shares authorized, 20,501,476 shares issued and outstanding at September 30, 2018; 5,766,891 shares issued and outstanding at December 31, 2017	2	1
Additional paid-in capital	86,987	56,254
Accumulated deficit	(68,532)	(54,185)
Total stockholders’ equity	18,457	2,070
Total liabilities and stockholders’ equity	$ 38,470	$ 33,526

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
Preferred stock, par value (usd per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	350,000,000	350,000,000
Common stock, shares issued (in shares)	20,501,476	5,766,891
Common stock, shares outstanding (in shares)	20,501,476	5,766,891
Series A Preferred Stock
Preferred stock, shares authorized (in shares)	17,500

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating expenses:
Research and development	$ 1,720	$ 1,068	$ 5,116	$ 5,079
General and administrative	1,341	3,222	10,130	9,350
Total operating expenses and operating loss	(3,061)	(4,290)	(15,246)	(14,429)
Non-operating income (expense):
Change in fair value of warrant liability	2,241	0	5,340	0
Change in fair value of contingent consideration	(162)	0	(4,025)	0
Loss on settlement of liability-classified warrants	0	0	(727)	0
Gain on extinguishment of debt	766	0	766	0
Interest expense, net	(74)	(102)	(292)	(360)
Total non-operating income (expense), net	2,771	(102)	1,062	(360)
Loss before income taxes	(290)	(4,392)	(14,184)	(14,789)
Income tax expense	0	63	163	180
Net loss	(290)	(4,455)	(14,347)	(14,969)
Deemed dividend arising from beneficial conversion feature of convertible preferred stock	0	0	(4,436)	0
Deemed dividend arising from the issuance of common stock to Series A convertible preferred stockholders under most favored nation provision	(8,654)	0	(8,654)	0
Impact of anti-dilution protection on liability-classified warrants	(491)	0	(491)	0
Net loss attributable to common stockholders	$ (9,435)	$ (4,455)	$ (27,928)	$ (14,969)
Per share information:
Net loss per common share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.53)	$ (2.27)	$ (2.75)	$ (4.56)
Weighted-average common shares outstanding, basic and diluted (in shares)	17,635,671	1,962,822	10,161,153	3,284,351

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY - 9 months ended Sep. 30, 2018 - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Patel vs Galena biopharma, Inc	Patel vs Galena biopharma, IncCommon Stock	Patel vs Galena biopharma, IncAdditional Paid-In Capital	Secured Debt	Secured DebtCommon Stock	Secured DebtAdditional Paid-In Capital	Convertible Preferred Stock	Convertible Preferred StockPreferred Stock	Convertible Preferred StockCommon Stock	Convertible Preferred StockAdditional Paid-In Capital	Convertible Notes Payable	Convertible Notes PayableCommon Stock	Convertible Notes PayableAdditional Paid-In Capital
Beginning balance (in shares) at Dec. 31, 2017		0	5,766,891
Beginning balance at Dec. 31, 2017	$ 2,070	$ 0	$ 1	$ 56,254	$ (54,185)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Stock (in shares)		10,700	6,845,000				228,672			715,277
Issuance of Series A convertible preferred stock, net of offering costs	9,647			9,647
Issuance of stock, amount	21,564		$ 1	21,563		$ 1,250		$ 1,250	$ 2,896		$ 2,896
Fair value of liability-classified warrants issued in connection with Series A convertible preferred stock offering	(5,039)			(5,039)
Beneficial conversion feature arising from Series A convertible preferred stock	(4,436)			(4,436)
Deemed dividend arising from beneficial conversion feature of Series A convertible preferred stock	4,436			4,436
Issuance of common stock (in shares)		2,898	499,682										(7,802)	3,748,184			118,644
Convertible preferred stock dividends	(487)			(487)
Issuance of common stock as result of conversion												$ (8,654)			$ (8,654)	$ 825		$ 825
Deemed dividend arising from the issuance of common stock to Series A convertible preferred stockholders under most favored nation provision	8,654			8,654
Impact of anti-dilution protection on liability-classified warrants	(491)			(491)
Issuance of common stock in connection with warrant exchange agreements (in shares)			54,343
Issuance of common stock in connection with warrant exchange agreements	285			285
Issuance of common stock upon exercise of pre-funded warrants			2,524,783
Stock-based compensation	284			284
Net loss	(14,347)				(14,347)
Ending balance (in shares) at Sep. 30, 2018		0	20,501,476
Ending balance at Sep. 30, 2018	$ 18,457	$ 0	$ 2	$ 86,987	$ (68,532)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net loss	$ (14,347)	$ (14,969)
Adjustment to reconcile net loss to net cash used in operating activities:
Gain on extinguishment of debt	(766)	0
Non-cash interest expense	134	258
Deferred taxes	49	7
Loss on extinguishment of payables	0	634
Non-cash stock-based compensation	284	3,776
Amortization of research and development expense		257
Fair value of common stock issued in exchange for services	0	325
Fair value of common stock issued in connection with litigation settlements	1,250	0
Change in fair value of common stock warrants	(5,340)	0
Change in fair value of contingent consideration	4,025	0
Loss on settlement of liability-classified warrants	727	0
Changes in operating assets and liabilities:
Other receivable	(6,600)	0
Prepaid expenses and other assets	(538)	3
Litigation settlement insurance recovery	(474)	0
Accounts payable	(4,453)	377
Accrued expenses and other current liabilities	182	85
Net cash used in operating activities	(25,867)	(9,247)
Cash flows from financing activities:
Net proceeds from issuance of Series A convertible preferred stock and common stock warrants	9,647	0
Proceeds from issuance of common stock	21,564	6,007
Dividends paid	(487)	0
Principal payments on long-term debt	(7,525)	(353)
Net cash provided by financing activities	23,199	5,654
Net decrease in cash, cash equivalents, restricted cash, and restricted cash equivalents	(2,668)	(3,593)
Cash, cash equivalents, restricted cash, and restricted cash equivalents at the beginning of period	12,750	5,962
Cash, cash equivalents, restricted cash, and restricted cash equivalents at the end of period	10,082	2,369
Supplemental disclosure of cash flow information:
Cash received during the periods for interest	166	0
Cash paid during the periods for interest	321	0
Supplemental disclosure of non-cash investing and financing activities:
Fair value of liability-classified warrants issued in connection with Series A convertible preferred stock recorded as issuance cost	5,039
Repayment of interest and principal on long-term debt through issuance of common stock	3,587	0
Reclassification of warrant liabilities upon exchange for shares of common stock	285	0
Impact of anti-dilution protection on liability-classified warrants	491	0
Debt issued in connection with warrant exchange agreements	$ 966	$ 0

Organization and Description of

Organization and Description of Business	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Organization and Description of Business	Organization and Description of Business Overview SELLAS Life Sciences Group, Inc. (the "Company," or “SELLAS”) is a late-stage biopharmaceutical company focused on the development and commercialization of novel cancer immunotherapeutics for a broad range of indications. Merger of Galena Biopharma, Inc. and SELLAS Life Sciences Group Ltd. As used in this quarterly report on Form 10-Q, the words the “Company,” and “SELLAS” refer to SELLAS Life Sciences Group, Inc. and its consolidated subsidiaries following completion of the business combination with Galena Biopharma, Inc., a Delaware corporation ("Galena"). This business combination is referred to as the Merger. On December 29, 2017, Galena completed the Merger with SELLAS Life Sciences Group, Ltd., a privately held Bermuda exempted company ("Private SELLAS"), in accordance with the terms of the Agreement and Plan of Merger and Reorganization, dated as of August 7, 2017 and amended November 5, 2017 (the "Merger Agreement"), among the Company, Sellas Intermediate Holdings I, Inc., Sellas Intermediate Holdings II, Inc., Galena Bermuda Merger Sub, Ltd., and Private SELLAS. As a result of the Merger, the Company’s business is now substantially comprised of the business of Private SELLAS, and although the Company is considered the legal acquiror of Private SELLAS, for accounting purposes, Private SELLAS is considered to have acquired the Company in the Merger. Consequently, the Merger was accounted for as a reverse acquisition and the Private SELLAS financial statements became the Company's financial statements. Immediately prior to the Merger, Galena effected a 1 -for- 30 reverse stock split of its outstanding common stock, par value $0.0001 per share. Under the terms of the Merger Agreement, Galena issued shares of its common stock to Private SELLAS’ securityholders at an exchange ratio of 43.9972 shares of its common stock in exchange for each common share of Private SELLAS outstanding immediately prior to the Merger. The Company also assumed all of the restricted stock units (“RSUs”) issued and outstanding under the Private SELLAS Stock Incentive Plan #1, and all of the issued and outstanding warrants of Private SELLAS. Accordingly, such RSUs will now be settled in, and such warrants now are exercisable for, shares of the Company’s common stock. Accordingly, immediately after the Merger, there were 5,766,891 shares of the Company’s common stock outstanding, with the former Private SELLAS securityholders owning 67.5% of the Company’s fully diluted common stock, and the Company’s pre-Merger securityholders owning the remaining 32.5% . The number of shares and per share amounts of common stock in the accompanying condensed consolidated financial statements and notes to the condensed consolidated financial statements have been restated to give retroactive effect to the common stock conversion ratio and reverse stock split for all periods presented, including common stock options, RSUs, and common stock warrants. Upon completion of the Merger, the Company’s name changed from “Galena Biopharma, Inc.” to “SELLAS Life Sciences Group, Inc.," the Company’s financial statements became those of Private SELLAS and the Company's common stock began trading on The Nasdaq Capital Market under a new ticker symbol “SLS” on January 2, 2018.

Liquidity

Liquidity	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Liquidity	Liquidity The Company has not generated any revenues, including from product sales, and has funded operations primarily from the proceeds of sales of its equity interests and convertible notes, as well as through the Merger. Substantial additional financing will be required by the Company to continue to fund its research and development activities. No assurance can be given that any such financing will be available when needed or that the Company’s research and development efforts will be successful. On July 16, 2018, the Company closed an underwritten public offering (the "July 2018 Offering"), issuing 6,845,000 shares of common stock and 4,675,000 pre-funded warrants exercisable for shares of common stock and accompanying common stock warrants to purchase an aggregate of 11,520,000 shares of common stock. The shares of common stock and accompanying common stock warrants were sold at a combined price of $2.10 per share and accompanying common stock warrant. The pre-funded warrants and accompanying common stock warrants were sold at a combined price of $2.0999 per pre-funded warrant and common stock warrant. Each common stock warrant sold with the shares of common stock and pre-funded warrants represents the right to purchase one share of the Company’s common stock at an exercise price of $2.10 per share. The common stock warrants are exercisable immediately and will expire on July 16, 2023, five years from the date of issuance. The pre-funded warrants are exercisable immediately, have an exercise price of $0.0001 per share, and will expire on July 16, 2023, five years from the date of issuance. The net proceeds to the Company from the July 2018 Offering, after deducting the underwriting discounts and commissions and other estimated July 2018 Offering expenses, and excluding the exercise of any warrants, were approximately $21.6 million . In addition to the proceeds from the July 2018 Offering, on March 7, 2018, the Company entered into a definitive securities purchase agreement to issue shares of its Series A convertible preferred stock (“Series A Convertible Preferred”) and warrants to purchase shares of its common stock in a private placement transaction to a select group of institutional investors. The sale of the aggregate 10,700 shares of Series A Convertible Preferred and 5.5 year warrants to acquire an aggregate of 1,383,631 shares of common stock at $6.59 per share closed in two tranches and resulted in aggregate gross proceeds to the Company of approximately $10.7 million . The Company closed the first tranche for approximately $6.0 million gross proceeds on March 9, 2018. The Company closed the second tranche of the remaining $4.7 million gross proceeds on May 1, 2018, following the receipt of necessary stockholder approval. The Company regularly explores alternative means of financing its operations and seeks funding through various sources, including public and private securities offerings, collaborative arrangements with third parties and other strategic alliances and business transactions. The Company currently does not have any commitments to obtain additional funds and may be unable to obtain sufficient funding in the future on acceptable terms, if at all. If the Company cannot obtain the necessary funding, it will need to delay, scale back or eliminate some or all of its research and development programs or enter into collaborations with third parties to commercialize potential products or technologies that it might otherwise seek to develop or commercialize independently, consider various other strategic alternatives, including a merger or sale of the Company, or cease operations. If the Company engages in collaborations, it may receive lower consideration upon commercialization of such products than if it had not entered into such arrangements or if it entered into such arrangements at later stages in the product development process. The Company has evaluated the guidance of Accounting Standards Codification ("ASC") 205-40, Presentation of Financial Statements - Going Concern , in order to determine whether there is substantial doubt about its ability to continue as a going concern for one year from the date its financial statements are available to be issued. The Company has prepared its condensed consolidated financial statements assuming that it will continue as a going concern, which contemplates realization of assets and the satisfaction of liabilities in the normal course of business. The Company has incurred net losses since inception and it expects to generate losses from operations for the foreseeable future primarily due to research and development costs for its potential product candidates, which raises substantial doubt about the Company’s ability to continue as a going concern. Various internal and external factors will affect whether and when the Company’s product candidates become approved drugs and how significant their market share will be, some of which are outside of the Company’s control. The length of time and cost of developing and commercializing these product candidates and/or failure of them at any stage of the drug approval process will materially affect the Company’s financial condition and future operations. The consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. As of September 30, 2018 , the Company had cash and cash equivalents of approximately $10.0 million , restricted cash balance of $0.1 million , other receivable of $6.6 million (received in November 2018), and $0.5 million in litigation insurance recovery (received in October 2018). In addition, the Company had outstanding accounts payable and accrued expenses of $11.9 million and indebtedness of $0.1 million as of September 30, 2018 . The Company expects its existing cash as of September 30, 2018 , including amounts received in October and November 2018, will enable the Company to fund its operating expenses and capital expenditure requirements through March 2019.

Basis Of Presentation and Signi

Basis Of Presentation and Significant Accounting Policies	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to U.S. GAAP as found in the ASC and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). Principles of Consolidation The condensed consolidated financial statements include the financial statements of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated upon consolidation. Unaudited Interim Results These condensed consolidated financial statements and accompanying notes should be read in conjunction with the Company's annual consolidated financial statements and the notes thereto included in its Annual Report on Form 10-K for the year ended December 31, 2017 , which was filed with the Securities and Exchange Commission ("SEC") on April 13, 2018 (the "2017 Annual Report"). The accompanying condensed consolidated financial statements at September 30, 2018 and for the three and nine months ended September 30, 2018 and 2017, are unaudited, but include all adjustments, consisting of normal recurring entries, that management believes to be necessary for a fair presentation of the periods presented. Interim results are not necessarily indicative of results for a full year. Balance sheet amounts as of December 31, 2017 have been derived from the audited financial statements as of that date. Preferred Stock The Company applies the accounting standards for distinguishing liabilities from equity when determining the classification and measurement of its preferred stock. Preferred shares subject to mandatory redemption are classified as liability instruments and are measured at fair value. Conditionally redeemable preferred shares (including preferred shares that feature redemption rights that are either within the control of the holder or subject to redemption upon the occurrence of uncertain events not solely within the Company’s control) are classified as temporary equity. At all other times, preferred shares are classified as stockholders’ equity. Convertible Instruments The Company applies the accounting standards for derivatives and hedging and for distinguishing liabilities from equity when accounting for hybrid contracts that feature conversion options. The accounting standards require companies to bifurcate conversion options from their host instruments and account for them as free-standing derivative financial instruments according to certain criteria. The criteria include circumstances in which (i) the economic characteristics and risks of the embedded derivative instrument are not clearly and closely related to the economic characteristics and risks of the host contract, (ii) the hybrid instrument that embodies both the embedded derivative instrument and the host contract is not re-measured at fair value under otherwise applicable generally accepted accounting principles with changes in fair value reported in earnings as they occur and (iii) a separate instrument with the same terms as the embedded derivative instrument would be considered a derivative instrument. Conversion options that contain variable settlement features such as provisions to adjust the conversion price upon subsequent issuances of equity or equity linked securities at exercise prices more favorable than that featured in the hybrid contract generally result in their bifurcation from the host instrument. The Company also records, when necessary, deemed dividends for the intrinsic value of the conversion options embedded in preferred stock based upon the difference between the fair value of the underlying common stock at the commitment date of the transaction and the effective conversion price embedded in the preferred stock. Recent Accounting Pronouncements Pending Adoption In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Accounting , which simplifies the accounting for share-based payments granted to nonemployees for goods and services. The ASU supersedes ASC 505-50 and expands the scope of ASC 718 to include all share-based payment arrangements related to the acquisition of goods and services from both nonemployees and employees. As a result, most of the guidance in ASC 718 associated with employee share-based payments, including most of its requirements related to classification and measurement, applies to nonemployee share-based payment arrangements. ASU 2018-07 generally requires an entity to use a modified retrospective transition approach, with a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year, for all (1) liability-classified nonemployee awards that have not been settled as of the adoption date and (2) equity-classified nonemployee awards for which a measurement date has not been established. The guidance is applicable to public business entities for fiscal years beginning after December 15, 2019 and interim periods within those years. The Company is currently evaluating the potential impact of the adoption of this standard on its consolidated results of operations, financial position and cash flows and related disclosures. In February 2016, the FASB issued ASU 2016-02 , Leases . In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842, Leases , and No. 2018-11, Leases (Topic 842) - Targeted Improvements . The new standard establishes a right-of-use , or ROU , model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. The new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. The Company is currently evaluating the potential impact of the adoption of the new standard on the consolidated financial statements. In August 2018, FASB issued ASU 2018-13, Fair Value Measurement (Topic 820) Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement . ASU 2018-13 modifies, adds and removes certain specific the disclosure requirements on fair value measurements in Topic 820 . The amendments in ASU 2018-13 are effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. Early adoption is permitted. An entity is permitted to early adopt any removed or modified disclosures upon issuance of ASU No. 2018-13 and delay adoption of the additional disclosures until their effective date. The Company is currently evaluating the potential impact of the adoption of the new standard on the consolidated financial statements. Recent Accounting Pronouncements Adopted In November 2016, the FASB issued ASU No. 2016-18, Restricted Cash . ASU No. 2016-18 requires that restricted cash be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown in the statement of cash flows. In accordance with ASU No. 2016-18, the Company adopted this standard in the first quarter of 2018. The adoption of this standard did not have a material impact on the Company's condensed consolidated financial statements. The following table provides a reconciliation of the components of cash, cash equivalents, restricted cash, and restricted cash equivalents reported in the Company's condensed consolidated balance sheets to the total of the amount presented in the condensed consolidated statements of cash flows (in thousands): September 30, 2018 December 31, 2017 Cash and cash equivalents $ 9,968 $ 2,319 Restricted cash and cash equivalents 114 10,431 Total cash, cash equivalents, restricted cash, and restricted cash equivalents $ 10,082 $ 12,750 In connection with the Company's Senior Secured Debenture described in Notes 7 and 8, the Company was required to maintain a minimum of the lesser of $18.5 million or the outstanding principal amount of unencumbered cash in a restricted account. Any funds in the restricted account in excess of the outstanding principal balance were to be transferred to the Company's unrestricted account to fund its ongoing operations. As of December 31, 2017, the Company maintained $10.2 million of cash and cash equivalents in a restricted account. The Senior Secured Debenture was deemed to be no longer outstanding as of September 30, 2018 . In addition, the Company maintained $0.1 million and $0.2 million as of September 30, 2018 and December 31, 2017, respectively, on hand with the Company's financial institutions as collateral for its corporate credit cards. In May 2017, the FASB issued ASU No. 2017-09, Scope of Modification Accounting . ASU No. 2017-09 clarifies which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting. This guidance is to be applied prospectively to awards modified on or after the adoption date and is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, with early adoption permitted. In accordance with ASU No. 2017-09, the Company adopted this standard prospectively in the first quarter of 2018. The adoption of ASU No. 2017-09 did not have a material impact on the Company's condensed consolidated financial statements. Reclassifications Certain prior year amounts have been reclassified to conform to current year presentation. These reclassifications had no effect on net loss per share.

Acquisition

Acquisition	9 Months Ended
	Sep. 30, 2018
Business Combinations [Abstract]
Acquisition	Acquisition On December 29, 2017, the Company completed the Merger with Private SELLAS as discussed in Note 1. The Merger was accounted for as a reverse merger under the acquisition method of accounting whereby Private SELLAS was considered to have acquired the Company for financial reporting purposes because, immediately upon completion of the Merger, Private SELLAS stockholders held a majority of the voting interest of the combined company. The following summary pro forma condensed consolidated financial information reflects the Merger with Galena as if it had occurred on January 1, 2017 for purposes of the statements of operations. This summary pro forma information is not necessarily representative of what the Company’s results of operations would have been had the Merger in fact occurred on January 1, 2017, and is not intended to project the Company’s results of operations for any future period. Three Months Ended September 30, 2017 Nine Months Ended September 30, 2017 Net loss $ (9,066 ) $ (21,690 ) Basic and diluted net loss per share $ (1.61 ) $ 4.92 Pro forma combined net loss includes an adjustment to reduce historical interest expense of $0.2 million and $0.3 million for the three and nine months ended September 30, 2017 , respectively, due to the conversion of the convertible notes of $5.8 million . The Company excluded a $5.2 million impairment charge incurred by the Company and $3.3 million of transaction costs related to the Merger from the pro forma financial information for the three and nine months ended September 30, 2017 .

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The following tables present information about the Company's assets and liabilities measured at fair value on a recurring basis in the condensed consolidated balance sheets (in thousands): Description September 30, 2018 Quoted Prices In Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Assets: Cash equivalents $ 6,774 $ 6,774 $ — $ — Total assets measured and recorded at fair value $ 6,774 $ 6,774 $ — $ — Liabilities: Warrants potentially settleable in cash $ 975 $ — $ — $ 975 Contingent consideration 5,319 — — 5,319 Total liabilities measured and recorded at fair value $ 6,294 $ — $ — $ 6,294 Description December 31, 2017 Quoted Prices In Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Assets: Cash equivalents $ 1,662 $ 1,662 $ — $ — Restricted cash equivalents 10,245 10,245 — — Total assets measured and recorded at fair value $ 11,907 $ 11,907 $ — $ — Liabilities: Warrants potentially settleable in cash $ 1,309 $ — $ — $ 1,309 Contingent consideration 1,294 — — 1,294 Total liabilities measured and recorded at fair value $ 2,603 $ — $ — $ 2,603 The Company did not transfer any financial instruments into or out of Level 3 classification during the three and nine months ended September 30, 2018 and 2017 . See Note 10 for a reconciliation of the changes in the fair value of the warrant liability for the nine months ended September 30, 2018 . A reconciliation of the change in the fair value of the contingent consideration liability for the nine months ended September 30, 2018 is as follows (in thousands): Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Contingent consideration, December 31, 2017 $ 1,294 Change in the estimated fair value of the contingent consideration 4,025 Contingent consideration, September 30, 2018 $ 5,319 The fair value of the contingent consideration is measured at the end of each reporting period using Level 3 inputs in a probability-weighted, discounted cash-outflow model. The contingent consideration relates to Galena’s acquisition of Apthera, Inc. in 2011 and the future contingent payments of up to $32.0 million based on the achievement of certain development and commercial milestones relating to the Company’s nelipepimut-S ("NeuVax TM" or "NPS") product candidate. The contingent consideration is payable at the election of the Company in either cash or shares of common stock, provided that the Company may not issue any shares in satisfaction of any contingent consideration unless it has first obtained approval of its stockholders in accordance with Rule 5635(a) of the Nasdaq Marketplace Rules. The significant unobservable assumptions include the probability of achieving each milestone, the date the Company expects to reach the milestone, and a determination of present value factors used to discount future expected cash outflows. The change in the estimated fair value of the contingent consideration during the nine months ended September 30, 2018 reflects an adjusted probability and timeline for the potential approval of NPS associated with the positive interim data in the triple-negative breast cancer cohort from the prospective, randomized, single-blinded, controlled Phase 2b investigator-sponsored clinical trial ("IST") of trastuzumab (Herceptin®) +/- NPS in HER2 1+/2+ breast cancer patients in the adjuvant setting to prevent recurrences that was announced on April 2, 2018.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	9 Months Ended
	Sep. 30, 2018
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consist of the following (in thousands): September 30, 2018 December 31, 2017 Professional fees* $ 2,836 $ 1,744 Compensation and related benefits 808 566 Clinical trial costs 583 51 Value-added tax 158 426 Rebates and returns of former commercial products 22 223 Other 276 191 Accrued expenses and other current liabilities $ 4,683 $ 3,201 *Includes approximately $2.5 million of legal fees incurred related to the JGB litigation as described in Note 8 that was reimbursed to the Company in November 2018 by JGB.

Debt

Debt	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Debt	Debt September 30, 2018 December 31, 2017 Debt Current portion of Senior Secured Debenture $ — $ 8,377 Short-term convertible promissory notes 76 — Non-current portion of Senior Secured Debenture — 2,611 Total debt $ 76 $ 10,988 Senior Secured Debenture On May 10, 2016, the Company's predecessor company, Galena, entered into a Securities Purchase Agreement (the “Securities Purchase Agreement”) with JGB (the "Purchaser") pursuant to which Galena sold to the JGB, at a 6.375% original issue discount, a $25.5 million Senior Secured Debenture (the "Senior Secured Debenture") and warrants to purchase up to 3,333 shares of the Company's common stock. Net proceeds to Galena from the sale of the Senior Secured Debenture and warrants, after payment of commissions and legal fees, were approximately $23.4 million . The Senior Secured Debenture originally matured November 10, 2018, with accrued interest at 9% per year, payable monthly. In addition, on the maturity date of the Senior Secured Debenture (or such earlier date that the principal amount of the Senior Secured Debenture is paid in full by acceleration or otherwise) a fixed amount, which would have been deemed interest under the Senior Secured Debenture, equal to $0.8 million was due and payable to JGB on such date in, at the option of the Company, cash and, subject to the same conditions for the payment of interest, in shares of the Company’s common stock, or a combination of cash and the Company’s common stock. The Company’s obligations under the Senior Secured Debenture were secured under a security agreement by a senior lien on all of the Company’s assets, including all of the Company’s interests in its consolidated subsidiaries. Private SELLAS was not a party to the security agreement. Under the terms of a subsidiary guarantee agreement, each subsidiary guaranteed the performance of the Company of the Securities Purchase Agreement, Senior Secured Debenture and related agreements. • The Company was required to maintain a minimum of the lesser of $18.5 million or the outstanding principal amount of unencumbered cash in a restricted account. Any funds in the restricted account in excess of the outstanding principal balance were transferred to the Company's unrestricted account to fund its ongoing operations. As of December 31, 2017 , the Company maintained $10.2 million of cash and cash equivalents in a restricted account. As of December 31, 2017 , the outstanding principal balance of the Senior Secured Debenture was $10.2 million . In addition to the outstanding principal balance, the Senior Secured Debenture had $0.8 million of additional interest that was included in the current portion of long-term debt as of December 31, 2017 . During the nine months ended September 30, 2018 , JGB redeemed $2.8 million of outstanding principal, which the Company satisfied with 659,529 shares of its common stock and redeemed $0.6 million of outstanding principal, which the Company satisfied with cash. As a result of the redemptions during 2018, the Company transferred $1.8 million of restricted cash into unrestricted cash and cash equivalents which was used to fund the Company’s ongoing operations. JGB commenced a lawsuit against the Company as described in Note 8 ("JGB Action"). On September 24, 2018, JGB unilaterally issued a directive to (i) the financial institution that maintained the restricted cash and cash equivalents and (ii) the manager of the account to liquidate all assets in the restricted account. As a result of such directive, approximately $8.5 million in cash was removed from the restricted account, $1.6 million in excess of the outstanding principal balance of the Senior Secured Debenture at the time of the removal. On October 16, 2018, JGB was required to deposit the $1.6 million excess that JGB removed from the restricted account into an escrow account, as ordered by the Court in the JGB Action, pending resolution of the dispute between the Company and JGB. On October 23, 2018, the Court entered an order, granting, among other things, the Company's Motion for Judgment seeking dismissal of JGB's amended complaint and allowing four of the Company's counterclaims to proceed to trial. As a result of the October 23rd Court order, on November 5, 2018, the parties to the JGB Action entered into a settlement agreement. The settlement agreement provides, among other things, that JGB make a one-time payment to the Company of $6.6 million , representing the $1.6 million excess cash removed from the amount in the restricted account from the outstanding principal balance of the Senior Secured Debenture and reimbursement of approximately $5.0 million of legal fees incurred by the Company. The Company recognized a gain on extinguishment of debt of $0.8 million that was previously accrued in long-term debt representing an additional interest payable at maturity as the amount is no longer required to be repaid by the Company. Accordingly, the Senior Secured Debenture is no longer outstanding and the related agreements have been terminated. Short-term Convertible Promissory Notes During the nine months ended September 30, 2018 , the Company entered into convertible promissory notes in the principal amount of $1.0 million in exchange for the surrender and cancellation of warrants to purchase 412,667 shares of its common stock pursuant to the February 2017 offering by Galena. The convertible promissory notes accrue interest at a rate of 5% per annum and the remaining outstanding principal balance and accrued interest is due and payable in November 2018. The outstanding principal balance and accrued interest is convertible into shares of the Company's common stock at a conversion price equal to $7.00 . In April 2018, $0.8 million of outstanding principal and accrued interest was converted into 118,644 shares of common stock. As of September 30, 2018 , $0.1 million principal balance and accrued interest remains outstanding.

Legal Proceedings, Commitments

Legal Proceedings, Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Legal Proceedings, Commitments and Contingencies	Legal Proceedings, Commitments and Contingencies Legal Proceedings From time to time, the Company is subject to various pending or threatened legal actions and proceedings, including those that arise in the ordinary course of its business, which may include employment matters, breach of contract disputes and stockholder litigation. Such actions and proceedings are subject to many uncertainties and to outcomes that are not predictable with assurance and that may not be known for extended periods of time. The Company records a liability in its condensed consolidated financial statements for costs related to claims, including future legal costs, settlements and judgments, when the Company has assessed that a loss is probable and an amount can be reasonably estimated. If the reasonable estimate of a probable loss is a range, the Company records the most probable estimate of the loss or the minimum amount when no amount within the range is a better estimate than any other amount. The Company discloses a contingent liability even if the liability is not probable or the amount is not estimable, or both, if there is a reasonable possibility that a material loss may have been incurred. In the opinion of management, as of the date hereof, the amount of liability, if any, with respect to these matters, individually or in the aggregate, will not materially affect the Company’s consolidated results of operations, financial position or cash flows. The Company’s predecessor company, Galena, was involved in multiple legal proceedings and administrative actions, including stockholder class actions, both state and federal, some of which are ongoing and to which the Company are now subject as a result of the Merger. The Company is also involved in litigation matters as follows: On February 13, 2017, putative shareholder securities class action complaints were filed in federal court alleging, among other things, that the Company and certain of the Company's former officers and directors failed to disclose that Galena’s promotional practices for Abstral ® (fentanyl sublingual tablets) were allegedly improper and that Galena may be subject to civil and criminal liability, and that these alleged failures rendered Galena’s statements about its business misleading. The actions were consolidated, lead plaintiffs were named by the Court and a consolidated complaint was filed. The Company filed a motion to dismiss the consolidated complaint. On August 21, 2018, the Company's motion to dismiss the consolidated complaint was granted without prejudice to file an amended complaint. On September 20, 2018, the plaintiffs filed an amended complaint. On October 22, 2018, the Company filed a motion to dismiss the amended complaint. In March 2017, a derivative complaint was filed in U.S. District Court for the District of New Jersey against the Company’s former directors and Galena, as a nominal defendant. In July 2017, a derivative complaint was filed in California state court against the Company’s former directors and Galena, as a nominal defendant. In January 2018, a derivative complaint was filed in the U.S. District Court for the District of New Jersey against the Company’s former directors, officers and employees, and the Company as a nominal defendant. In June 2018, a derivative complaint was filed in U.S. District Court for the Northern District of California against the Company’s current and former directors, and the Company as a nominal defendant. The plaintiff in the June 2018 case voluntarily withdrew his complaint from the U.S District Court of the Northern District of California and on August 27, 2018 refiled the complaint in the Court of Chancery of the State of Delaware. These complaints purport to assert derivative claims for breach of fiduciary duty on the Company’s behalf against the Company’s former directors and, in certain of the complaints, the Company’s current directors, and the Company’s former officers and former employees, based on substantially similar facts as alleged in the putative shareholder securities class action complaints mentioned above. The March 2017, July 2017, and January 2018 lawsuits are currently stayed pending resolution of motions to dismiss in the referenced securities class action. On October 29, 2018, the defendants in the August 2018 lawsuit notified the plaintiff of its intent to file a motion to dismiss the lawsuit. In April 2017, a putative stockholder class action, captioned Patel vs. Galena Biopharma Inc. et. al, was filed in Delaware state court seeking relief under Section 225 of the Delaware General Corporation Law ("DGCL") and alleging breaches of fiduciary duties by Galena’s former board of directors and former interim chief executive officer regarding the proposals to amend Galena’s certificate of incorporation to increase the amount of authorized shares of common stock and effectuate a reverse stock split at the July 2016 and October 2016 stockholder meetings, respectively. On June 2, 2017, an amended verified complaint was filed along with a motion to expedite the proceedings. On June 20, 2017, the Court consolidated the claims into In re Galena Biopharma, Inc., C. A. No. 2017-0423-JTL. On July 24, 2017, Galena entered into a binding settlement term sheet, involving payment of $50,000 in cash and $1,250,000 in unrestricted shares of common stock. The Court enforced the settlement term sheet on November 30, 2017. On February 22, 2018, the plaintiff filed his brief in support of the settlement as well as his request for attorneys’ fees and an incentive award. On June 14, 2018, the Court entered an Order and Final Judgment approving the settlement and awarding attorneys’ fees to the plaintiff. All obligations related to the Order and Final Judgment were satisfied in full by the Company in June 2018. In October 2018, the Company received $0.5 million from its insurance carrier for previous amounts paid by the Company in excess of its deductible. The amount is recorded as a litigation insurance recovery as of September 30, 2018 in the Company's condensed consolidated balance sheet. On or about April 9, 2018, JGB filed a lawsuit in the U.S. District Court for the Southern District of New York (the "Court") captioned JGB (Cayman) Newton, Ltd. v. Sellas Life Sciences Group, Inc., et al., Case 1:18-cv-3095 (DLC) (the "JGB Action"). The complaint in the JGB Action asserted claims under state law and federal securities law against the Company, the Company's Chief Executive Officer, Angelos M. Stergiou, M.D., ScD h.c., and the Company's former Interim Chief Financial Officer, Aleksey N. Krylov. On or about May 2, 2018, JGB filed an amended complaint, adding as defendants Jane Wasman, Stephen Ghiglieri, David Scheinberg, M.D., Robert Van Nostrand and John Varian, each of whom is a member of the Company's Board of Directors. On May 18, 2018, the Company filed an answer to the amended complaint and filed seven counterclaims. On June 18, 2018, the Company filed a motion for judgment on the pleadings and a motion to dismiss the amended complaint. On July 6, 2018, JGB filed a motion for partial judgment on the pleadings and motion to dismiss all of the Company's counterclaims. On September 24, 2018, without any prior written notice, JGB unilaterally directed that all of the funds, approximately $8.5 million in cash, be removed from the restricted account, an amount in excess of the outstanding principal balance of the Senior Secured Debenture. On October 23, 2018, the Court entered an Opinion and Order, granting, in full, the Company's motion to dismiss JGB's amended complaint and allowing four of the Company's counterclaims to proceed to trial. Following the October 23 Opinion and Order of the Court, the parties to the JGB Action entered into a settlement agreement on November 5, 2018. The settlement agreement provides, among other things, that JGB will make a one-time payment to the Company of $6.6 million , inclusive of the $1.6 million excess amount removed from the restricted account. The entire settlement amount was recorded as an other receivable as of September 30, 2018 in the condensed consolidated balance sheet as of September 30, 2018 and the amount was received in November 2018. The Company offset approximately $2.5 million of legal fees incurred during the three months ended September 30, 2018 previously recorded in general and administrative expense in the condensed consolidated statement of operations with proceeds from the settlement and $2.5 million legal fees incurred subsequent to September 30, 2018 recorded as an accrued liability in the condensed consolidated balance sheet. The Company recognized a gain on extinguishment of debt of $0.8 million that was previously accrued in long-term debt for an additional interest payable at maturity as the amount is no longer payable by the Company. The settlement agreement also provides for the termination of the Senior Secured Debenture and all ancillary agreements, including the security agreement covering the Company's assets as well as a release of all security interests in the collateral.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Preferred Stock The Company has authorized up to 5,000,000 shares of preferred stock, $0.0001 par value per share, for issuance. Series A Convertible Preferred On March 7, 2018, the Company entered into a securities purchase agreement with investors, pursuant to which the Company agreed to sell to the investors, in a private placement pursuant to Rule 4(a)(2) and Regulation S under the Securities Act, an aggregate of 10,700 shares of the Company’s newly-created non-voting Series A Convertible Preferred, and warrants to acquire an aggregate 1,383,631 shares of the Company’s common stock, par value $0.0001 per share at an aggregate purchase price of $10.7 million . The Series A Convertible Preferred was initially convertible into 1,844,835 shares of common stock based on an initial conversion price of $5.80 per share. At the first closing of the Series A Convertible Preferred on March 9, 2018, the Company issued an aggregate 5,987 shares of Series A Convertible Preferred and warrants to acquire 774,186 shares of common stock for aggregate gross proceeds of $6.0 million . The second closing of the remaining 4,713 shares of the Series A Convertible Preferred and warrants to acquire 609,445 shares of its common stock, for aggregate gross proceeds of $4.7 million , occurred on May 1, 2018 following receipt of stockholder approval. In the event of a "qualified offering," as defined in the securities purchase agreement, holders of the Series A Convertible Preferred (the "Series A Holders"), had the right to exchange their shares of Series A Convertible Preferred for the same securities sold in a qualified offering on a $1.00 for $1.00 basis based on the stated value of their shares of Series A Convertible Preferred under the most favored nation provision. On July 16, 2018, following consummation of the July 2018 Offering, which was deemed a qualified offering as described below and also in Note 2 above, the Series A Holders exchanged an aggregate of $7,871,186 of stated valued and accrued but unpaid dividends on their Series A Convertible Preferred for an aggregate of 3,748,184 shares of the Company’s common stock and warrants to purchase an aggregate of 3,748,184 shares of the Company’s common stock. Following such exchange there are no shares of Series A Convertible Preferred issued and outstanding. The warrants have an exercise price of $2.10 per share and a term of five years. The fair value of the common stock and warrants to purchase shares of common stock exceeded the carrying amount of the Series A Preferred by $8.7 million and that amount is recorded as a deemed dividend in the condensed consolidated statements of operations during the three and nine months ended September 30, 2018 as it represents a transfer of value from the common stockholders to the preferred investors. Since the Company does not have accumulated earnings, the deemed dividend is taken from additional paid-in capital. This one-time, non-cash charge impacted net loss attributable to common stockholders and loss per share for the three and nine months ended September 30, 2018 . In addition, pursuant to the terms of the warrants, the exercise price of the warrants issued to the investors in March 2018 and May 2018 was adjusted to $2.10 per share from the original exercise price of $6.59 per share. The Company recognized the $0.5 million increase to the fair value of the warrant liability as a result of the adjusted stock price as a deemed dividend in the condensed consolidated statements of operations during the three and nine months ended September 30, 2018 . This one-time, non-cash charge impacted net loss attributable to common stockholders and loss per share for the three and nine months ended September 30, 2018 . The Series A Convertible Preferred generally had no voting rights. However, for so long as any shares of Series A Convertible Preferred were outstanding, the affirmative vote of the holders of a majority of the then outstanding shares of the Series A Convertible Preferred was required to: (a) alter or change adversely the powers, preferences or rights given to the Series A Convertible Preferred or alter or amend the Certificate of Designation, (b) authorize or create any class of stock ranking as to dividends, redemption or distribution of assets upon a Liquidation (as defined in the Certificate of Designation) senior to, or otherwise pari passu with, the Series A Convertible Preferred, (c) amend the Company's certificate of incorporation or other charter documents in any manner that adversely affects any rights of the holders of Series A Convertible Preferred, (d) increase the number of authorized shares of Series A Convertible Preferred, or (e) enter into any agreement with respect to any of the foregoing. Upon any liquidation, dissolution or winding-up of the Company, whether voluntary or involuntary that is not a Fundamental Transaction (as defined in the Certificate of Designation), the holders of Series A Convertible Preferred were entitled to receive from the Company's assets the same amount they would have received on an as converted basis, disregarding any conversion limitations. Such amounts would have been paid on a pari passu basis with all holders of common stock. The Company evaluated the Series A Convertible Preferred in accordance with the provisions of ASC 815, Derivatives and Hedging , including consideration of embedded derivatives requiring bifurcation. The issuance of the Series A Convertible Preferred could generate a beneficial conversion feature (“BCF”), which arises when a debt or equity security is issued with an embedded conversion option that is beneficial to the investor or in the money at inception because the conversion option has an effective conversion price that is less than the market price of the underlying stock at the commitment date. The Company recognized the BCF by allocating the intrinsic value of the conversion option, which is the number of shares of common stock available upon conversion multiplied by the difference between the effective conversion price per share and the fair value of common stock per share on the commitment date, to additional paid-in capital, resulting in a discount on the convertible preferred stock. As the Series A Convertible Preferred could have been converted immediately, the Company recognized a BCF of $2.0 million as a deemed dividend in the condensed consolidated statements of operations related to the first closing on March 9, 2018 and an additional BCF of $2.5 million as a deemed dividend related to the second closing on May 1, 2018. These one-time, non-cash charges impacted net loss attributable to common stockholders and loss per share for the nine months ended September 30, 2018 . Common Stock The Company has authorized up to 350,000,000 shares of common stock, $0.0001 par value per share, for issuance. On July 16, 2018, the Company closed the July 2018 Offering, issuing 6,845,000 shares of common stock and 4,675,000 pre-funded warrants exercisable for shares of common stock and accompanying common stock warrants to purchase an aggregate of 11,520,000 shares of common stock. The shares of common stock and accompanying common stock warrants were sold at a combined price of $2.10 per share and accompanying common stock warrant. The pre-funded warrants and accompanying common stock warrants were sold at a combined price of $2.0999 per pre-funded warrant and common stock warrant. Each accompanying common stock warrant sold with the shares of common stock and pre-funded warrants represents the right to purchase one share of the Company’s common stock at an exercise price of $2.10 per share. The common stock warrants are exercisable immediately and will expire on July 16, 2023, five years from the date of issuance. The pre-funded warrants are exercisable immediately, have an exercise price of $0.0001 per share, and will expire on July 16, 2023, five years from the date of issuance. The net proceeds to the Company from the July 2018 Offering, after deducting the underwriting discounts and commissions and other estimated offering expenses, and excluding the exercise of any warrants, were approximately $21.6 million . During its evaluation of equity classification for the pre-funded warrants exercisable for shares of common stock and warrants to acquire shares of common stock issued in the July 2018 Offering, the Company considered the conditions as prescribed within ASC 815-40, Derivatives and Hedging , Contracts in an Entity’s own Equity (“ASC 815-40”). The conditions within ASC 815-40 are not subject to a probability assessment. The pre-funded warrants exercisable for shares of common stock and warrants to acquire shares of common stock do not fall under the liability criteria within ASC 480, Distinguishing Liabilities from Equity, as they are not puttable and do not represent an instrument that has a redeemable underlying security. The pre-funded warrants exercisable for shares of common stock and warrants to acquire shares of common stock do meet the definition of a derivative instrument under ASC 815, but are eligible for the scope exception as they are indexed to the Company’s own stock and would be classified in permanent equity if freestanding. Shares of common stock for future issuance are reserved for as follows (in thousands): September 30, 2018 Warrants outstanding 19,224 Stock options outstanding 434 Options reserved for future issuance under the Company’s 2017 Equity Incentive Plan 381 Shares reserved for future issuance under the Employee Stock Purchase Plan 115 Restricted stock units 13 Total reserved for future issuance 20,167

Warrants to Acquire Shares of C

Warrants to Acquire Shares of Common Stock	9 Months Ended
	Sep. 30, 2018
Warrants and Rights Note Disclosure [Abstract]
Warrants to Acquire Shares of Common Stock	Warrants to Acquire Shares of Common Stock The following is a summary of the Company's warrants to acquire shares of common stock activity for the nine months ended September 30, 2018 (in thousands): Warrant Issuance Outstanding, December 31, 2017 Granted Exercised Canceled/Expired Outstanding, September 30, 2018 Expiration July 2018 Offering — 15,268 — — 15,268 July 2023 Pre-funded July 2018 Offering — 4,675 (2,525 ) — 2,150 July 2023 Series A Convertible Preferred — 1,384 — 1,384 September 2023 2017 Equilibria 316 — — 316 December 2022 Galena February 2017 567 — — (535 ) 32 February 2022 Galena Other 80 — — (6 ) 74 January 2022 963 21,327 (2,525 ) (541 ) 19,224 Warrants to acquire shares of common stock consist of warrants that may be settled in cash, which are liability-classified warrants, and equity-classified warrants. During the nine months ended September 30, 2018 , a total of 534,333 of the Galena February 2017 liability-classified warrants to purchase shares of common stock were canceled under various warrant exchange agreements. The Company issued 54,613 shares of its common stock in exchange for the surrender and cancellation of warrants to acquire 121,667 shares of its common stock and $1.0 million in convertible promissory notes in exchange for the surrender and cancellation of warrants to acquire 412,667 shares of its common stock, as described in Note 7. The fair value of the common stock and promissory notes exchanged totaled $1.2 million , which exceeded the fair value of the warrant liability of the warrants canceled by $0.7 million and is recorded as loss on settlement of liability-classified warrants in the condensed consolidated statement of operations for the nine months ended September 30, 2018 . In April 2018, $0.8 million of outstanding principal and accrued interest was converted into 118,644 shares of common stock. Warrants Classified as Liabilities Liability-classified warrants consist of warrants to acquire common stock issued in connection with previous equity financings for the Series A Convertible Preferred, Galena's February 2017 financing, and various other Galena equity financings that were assumed by the Company at the consummation of the Merger. These warrants may be settled in cash and were determined to not be indexed to the Company’s common stock. Prior to the consummation of the July 2018 Offering, the initial exercise price of the warrants to acquire shares of common stock in connection with the Series A Convertible Preferred was $6.59 per share of common stock, subject to standard adjustments for certain transactions affecting the Company’s securities (such as stock dividends, and stock splits). From the original issue date until the one-year anniversary of a qualified offering, the initial exercise price and number of warrants to acquire shares of common stock are subject to anti-dilution protection in the event of non-exempt equity issuances at a price per share lower than the then exercise price (the "Base Share Price"). Simultaneously with the consummation of each non-exempt equity issuance the exercise price shall be reduced to equal the Base Share Price. Such adjustment shall be made whenever such common stock or common stock equivalents are issued. The estimated fair value of outstanding warrants accounted for as liabilities is determined at each balance sheet date. Any decrease or increase in the estimated fair value of the warrant liability since the most recent balance sheet date is recorded in the condensed consolidated statement of operations as change in fair value of warrant liability. The fair value of the warrants is estimated using a Black-Scholes pricing model with the following inputs: As of September 30, 2018 Warrant Issuance Outstanding (in thousands) Strike price (per share) Expected term (years) Volatility % Risk-free rate % Series A Convertible Preferred 1,384 $ 2.10 5.01 83.18 % 2.94 % Galena February 2017 32 $ 33.00 3.38 85.39 % 2.25 % Galena Other 74 $ 888.22 2.68 85.96 % 2.32 % As of December 31, 2017 Warrant Issuance Outstanding (in thousands) Strike price (per share) Expected term (years) Volatility % Risk-free rate % Galena February 2017 567 $ 13.00 4.12 79.29 % 2.09 % Galena Other 80 $ 28.40 3.19 74.05 % 2.09 % The expected volatility assumptions are based on the Company's implied volatility in combination with the implied volatilities of similar publicly traded entities. The expected life assumption is based on the remaining contractual terms of the warrants. The risk-free rate is based on the zero coupon rates in effect at the time of valuation. The dividend yield used in the pricing model is zero , because the Company has no present intention to pay cash dividends. The changes in fair value of the warrant liability for the nine months ended September 30, 2018 were as follows (in thousands): Warrant Issuance Warrant liability, December 31, 2017 Fair value of warrants granted Fair value of warrants canceled Adjustment to exercise price of warrants Change in fair value of warrants Warrant liability, September 30, 2018 Series A Convertible Preferred $ — $ 5,039 $ — $ 491 $ (4,558 ) $ 972 Galena February 2017 1,305 — (524 ) — (778 ) 3 Galena Other 4 — — — (4 ) — $ 1,309 $ 5,039 $ (524 ) $ 491 $ (5,340 ) $ 975 Warrants Classified as Equity The Company issued warrants to acquire 316,163 shares of the its common stock at an exercise price of $7.42 per share, maturing five years from issuance, to EQC Private Markets SAC Fund Ltd-EQC Biotech Sely I Fund on December 29, 2017. These warrants are recorded in equity at fair value upon issuance, and not as liabilities, and are not subject to adjustment to fair value in subsequent reporting periods. The fair value of the warrants granted was $5.60 per share using the Black-Scholes pricing model with the fair value assumptions for the grant including a volatility of 90.10% , expected term of five years, risk free rate of 2.20% , and a dividend rate of 0.00 . The pre-funded warrants exercisable for shares of common stock and warrants to acquire shares of common stock issued during the July 2018 offering are recorded in equity upon issuance as described in Note 9.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation Share and per share amounts below have been retroactively adjusted to reflect the exchange ratio and reverse stock split as described in Note 1. 2017 Equity Incentive Plan On December 29, 2017, the 2017 Equity Incentive Plan was approved, and currently allows for the issuance of up to a maximum of approximately 575,000 shares of common stock in connection with the grant of stock-based awards, including stock options, restricted stock, restricted stock units, stock appreciation rights and other types of awards as deemed appropriate, not including shares subject to awards assumed in connection with certain transactions, including the Merger. Upon the consummation of the Merger, the Company assumed approximately 10,171 shares subject to outstanding common stock options granted under the Company’s 2016 Incentive Plan that will remain exercisable through December 29, 2018 for former Company employees and directors. The number of shares reserved for issuance under the 2017 Equity Incentive Plan will automatically increase on January 1 of each year, for a period of not more than ten years, commencing on January 1 of the year following the year in which the effective date occurs and ending on (and including) January 1, 2027, in an amount equal to 4% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year. Notwithstanding the foregoing, the board of directors may act prior to January 1 of a given year to provide that there will be no January 1 increase in the share reserve for such year or that the increase in the share reserve for such year will be a lesser number of shares of common stock than would otherwise occur pursuant to the preceding sentence. The number of shares reserved for issuance under the 2017 Equity Incentive Plan was automatically increased to approximately 805,000 on January 1, 2018. As of September 30, 2018 , an aggregate of approximately 381,000 shares of common stock were reserved for future grants under the Company’s 2017 Equity Incentive Plan. There were no common stock options granted under the 2017 Equity Incentive Plan for the year ended December 31, 2017. The following table summarizes the components of stock-based compensation expense in the condensed consolidated statements of operations for the three and nine months ended September 30, 2018 and 2017 , respectively (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Research and development $ 21 $ 543 $ 55 $ 729 General and administrative 115 724 229 3,047 Total stock-based compensation $ 136 $ 1,267 $ 284 $ 3,776 Options to Purchase Shares of Common Stock The Company uses the Black-Scholes option-pricing model and the following assumptions were used to determine the fair value of all its stock options granted during the nine months ended September 30, 2018: Nine Months Ended September 30, 2018 Risk free interest rate 2.73 % Volatility 80.83 % Expected lives (years) 6.20 Expected dividend yield — % The weighted-average grant date fair value of options granted during the nine months ended September 30, 2018 was $3.73 . There were no stock options granted during the three months ended September 30, 2018 and the nine months ended September 30, 2017 . The Company’s expected common stock price volatility assumption is based upon the Company's own implied volatility in combination with the implied volatility of a basket of comparable companies. The expected life assumptions for employee grants were based upon the simplified method, which averages the contractual term of the Company’s options of ten years with the average vesting term of four years for an average of six years . The expected life assumptions for non-employees were based upon the contractual term of the option. The dividend yield assumption is zero , because the Company has never paid cash dividends and presently has no intention to do so. The risk-free interest rate used for each grant was also based upon prevailing short-term interest rates. The Company accounts for forfeitures as they occur. As of September 30, 2018 , there was $1.2 million of unrecognized compensation cost related to outstanding stock options that is expected to be recognized as a component of the Company’s operating expenses over a weighted-average period of 2.46 years. The following table summarizes stock option activity of the Company for the nine months ended September 30, 2018 : Total Number of Shares (In Thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (In Thousands) Outstanding at January 1, 2018 10 $ 1,240.55 1.00 $ — Granted 483 5.24 — Canceled (59 ) 5.24 $ — Outstanding at September 30, 2018 434 $ 34.17 9.26 $ — Options exercisable at September 30, 2018 43 $ 265.35 7.51 $ — The aggregate intrinsic values of outstanding and exercisable stock options at September 30, 2018 were calculated based on the closing price of the Company’s common stock as reported on the Nasdaq Capital Market on September 30, 2018 of $1.22 per share. The aggregate intrinsic value equals the positive difference between the closing fair market value of the Company’s common stock and the exercise price of the underlying stock options. RSUs with Time-Based and Performance-Based Conditions The Company granted RSUs subject to both time-based and performance-based vesting conditions to certain of its employees and non-employees pursuant to the 2016 Incentive Plan. These RSUs vest based on both (i) continued service either over a three -year measurement period or at the end of the required service period and (ii) the achievement of a liquidity event. The initial vesting date for these RSUs was February 27, 2018. The liquidity event, as defined in the relevant RSU grant agreements, will be satisfied upon the earlier of either: (a) change of control or (b) a qualified public offering. As of September 30, 2018 and December 31, 2017, there were approximately 13,000 RSUs outstanding with a weighted average grant date fair value of $52.94 . The Company recognizes compensation expense related to these RSUs when the liquidity event is deemed probable. As such, no compensation expense was recorded to date as the liquidity event is outside the Company’s control and not deemed probable until it occurs.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company evaluated all events or transactions that occurred after September 30, 2018 up through the date these financial statements were issued. Other than as disclosed elsewhere in the notes to the condensed consolidated financial statements, the Company did not have any material subsequent events.

Basis Of Presentation and Sig_2

Basis Of Presentation and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to U.S. GAAP as found in the ASC and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).
Principles of Consolidation	Principles of Consolidation The condensed consolidated financial statements include the financial statements of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated upon consolidation.
Preferred Stock	Preferred Stock The Company applies the accounting standards for distinguishing liabilities from equity when determining the classification and measurement of its preferred stock. Preferred shares subject to mandatory redemption are classified as liability instruments and are measured at fair value. Conditionally redeemable preferred shares (including preferred shares that feature redemption rights that are either within the control of the holder or subject to redemption upon the occurrence of uncertain events not solely within the Company’s control) are classified as temporary equity. At all other times, preferred shares are classified as stockholders’ equity.
Convertible Instruments	Convertible Instruments The Company applies the accounting standards for derivatives and hedging and for distinguishing liabilities from equity when accounting for hybrid contracts that feature conversion options. The accounting standards require companies to bifurcate conversion options from their host instruments and account for them as free-standing derivative financial instruments according to certain criteria. The criteria include circumstances in which (i) the economic characteristics and risks of the embedded derivative instrument are not clearly and closely related to the economic characteristics and risks of the host contract, (ii) the hybrid instrument that embodies both the embedded derivative instrument and the host contract is not re-measured at fair value under otherwise applicable generally accepted accounting principles with changes in fair value reported in earnings as they occur and (iii) a separate instrument with the same terms as the embedded derivative instrument would be considered a derivative instrument. Conversion options that contain variable settlement features such as provisions to adjust the conversion price upon subsequent issuances of equity or equity linked securities at exercise prices more favorable than that featured in the hybrid contract generally result in their bifurcation from the host instrument. The Company also records, when necessary, deemed dividends for the intrinsic value of the conversion options embedded in preferred stock based upon the difference between the fair value of the underlying common stock at the commitment date of the transaction and the effective conversion price embedded in the preferred stock.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Pending Adoption In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Accounting , which simplifies the accounting for share-based payments granted to nonemployees for goods and services. The ASU supersedes ASC 505-50 and expands the scope of ASC 718 to include all share-based payment arrangements related to the acquisition of goods and services from both nonemployees and employees. As a result, most of the guidance in ASC 718 associated with employee share-based payments, including most of its requirements related to classification and measurement, applies to nonemployee share-based payment arrangements. ASU 2018-07 generally requires an entity to use a modified retrospective transition approach, with a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year, for all (1) liability-classified nonemployee awards that have not been settled as of the adoption date and (2) equity-classified nonemployee awards for which a measurement date has not been established. The guidance is applicable to public business entities for fiscal years beginning after December 15, 2019 and interim periods within those years. The Company is currently evaluating the potential impact of the adoption of this standard on its consolidated results of operations, financial position and cash flows and related disclosures. In February 2016, the FASB issued ASU 2016-02 , Leases . In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842, Leases , and No. 2018-11, Leases (Topic 842) - Targeted Improvements . The new standard establishes a right-of-use , or ROU , model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. The new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. The Company is currently evaluating the potential impact of the adoption of the new standard on the consolidated financial statements. In August 2018, FASB issued ASU 2018-13, Fair Value Measurement (Topic 820) Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement . ASU 2018-13 modifies, adds and removes certain specific the disclosure requirements on fair value measurements in Topic 820 . The amendments in ASU 2018-13 are effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. Early adoption is permitted. An entity is permitted to early adopt any removed or modified disclosures upon issuance of ASU No. 2018-13 and delay adoption of the additional disclosures until their effective date. The Company is currently evaluating the potential impact of the adoption of the new standard on the consolidated financial statements. Recent Accounting Pronouncements Adopted In November 2016, the FASB issued ASU No. 2016-18, Restricted Cash . ASU No. 2016-18 requires that restricted cash be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown in the statement of cash flows. In accordance with ASU No. 2016-18, the Company adopted this standard in the first quarter of 2018. The adoption of this standard did not have a material impact on the Company's condensed consolidated financial statements. The following table provides a reconciliation of the components of cash, cash equivalents, restricted cash, and restricted cash equivalents reported in the Company's condensed consolidated balance sheets to the total of the amount presented in the condensed consolidated statements of cash flows (in thousands): September 30, 2018 December 31, 2017 Cash and cash equivalents $ 9,968 $ 2,319 Restricted cash and cash equivalents 114 10,431 Total cash, cash equivalents, restricted cash, and restricted cash equivalents $ 10,082 $ 12,750 In connection with the Company's Senior Secured Debenture described in Notes 7 and 8, the Company was required to maintain a minimum of the lesser of $18.5 million or the outstanding principal amount of unencumbered cash in a restricted account. Any funds in the restricted account in excess of the outstanding principal balance were to be transferred to the Company's unrestricted account to fund its ongoing operations. As of December 31, 2017, the Company maintained $10.2 million of cash and cash equivalents in a restricted account. The Senior Secured Debenture was deemed to be no longer outstanding as of September 30, 2018 . In addition, the Company maintained $0.1 million and $0.2 million as of September 30, 2018 and December 31, 2017, respectively, on hand with the Company's financial institutions as collateral for its corporate credit cards. In May 2017, the FASB issued ASU No. 2017-09, Scope of Modification Accounting . ASU No. 2017-09 clarifies which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting. This guidance is to be applied prospectively to awards modified on or after the adoption date and is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, with early adoption permitted. In accordance with ASU No. 2017-09, the Company adopted this standard prospectively in the first quarter of 2018. The adoption of ASU No. 2017-09 did not have a material impact on the Company's condensed consolidated financial statements. Reclassifications Certain prior year amounts have been reclassified to conform to current year presentation. These reclassifications had no effect on net loss per share.

Basis Of Presentation and Sig_3

Basis Of Presentation and Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Schedule of Cash and Cash Equivalents	The following table provides a reconciliation of the components of cash, cash equivalents, restricted cash, and restricted cash equivalents reported in the Company's condensed consolidated balance sheets to the total of the amount presented in the condensed consolidated statements of cash flows (in thousands): September 30, 2018 December 31, 2017 Cash and cash equivalents $ 9,968 $ 2,319 Restricted cash and cash equivalents 114 10,431 Total cash, cash equivalents, restricted cash, and restricted cash equivalents $ 10,082 $ 12,750

Acquisition (Tables)

Acquisition (Tables)	9 Months Ended
	Sep. 30, 2018
Business Combinations [Abstract]
Summary of Pro Forma Information	The following summary pro forma condensed consolidated financial information reflects the Merger with Galena as if it had occurred on January 1, 2017 for purposes of the statements of operations. This summary pro forma information is not necessarily representative of what the Company’s results of operations would have been had the Merger in fact occurred on January 1, 2017, and is not intended to project the Company’s results of operations for any future period. Three Months Ended September 30, 2017 Nine Months Ended September 30, 2017 Net loss $ (9,066 ) $ (21,690 ) Basic and diluted net loss per share $ (1.61 ) $ 4.92

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Contingent Purchase Price Consideration, Measured at Estimated Fair Value on Recurring Basis	The following tables present information about the Company's assets and liabilities measured at fair value on a recurring basis in the condensed consolidated balance sheets (in thousands): Description September 30, 2018 Quoted Prices In Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Assets: Cash equivalents $ 6,774 $ 6,774 $ — $ — Total assets measured and recorded at fair value $ 6,774 $ 6,774 $ — $ — Liabilities: Warrants potentially settleable in cash $ 975 $ — $ — $ 975 Contingent consideration 5,319 — — 5,319 Total liabilities measured and recorded at fair value $ 6,294 $ — $ — $ 6,294 Description December 31, 2017 Quoted Prices In Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Assets: Cash equivalents $ 1,662 $ 1,662 $ — $ — Restricted cash equivalents 10,245 10,245 — — Total assets measured and recorded at fair value $ 11,907 $ 11,907 $ — $ — Liabilities: Warrants potentially settleable in cash $ 1,309 $ — $ — $ 1,309 Contingent consideration 1,294 — — 1,294 Total liabilities measured and recorded at fair value $ 2,603 $ — $ — $ 2,603
Reconciliation of Level 3 Liabilities	A reconciliation of the change in the fair value of the contingent consideration liability for the nine months ended September 30, 2018 is as follows (in thousands): Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Contingent consideration, December 31, 2017 $ 1,294 Change in the estimated fair value of the contingent consideration 4,025 Contingent consideration, September 30, 2018 $ 5,319

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2018
Payables and Accruals [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consist of the following (in thousands): September 30, 2018 December 31, 2017 Professional fees* $ 2,836 $ 1,744 Compensation and related benefits 808 566 Clinical trial costs 583 51 Value-added tax 158 426 Rebates and returns of former commercial products 22 223 Other 276 191 Accrued expenses and other current liabilities $ 4,683 $ 3,201 *Includes approximately $2.5 million of legal fees incurred related to the JGB litigation as described in Note 8 that was reimbursed to the Company in November 2018 by JGB.

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Schedule of Debt	September 30, 2018 December 31, 2017 Debt Current portion of Senior Secured Debenture $ — $ 8,377 Short-term convertible promissory notes 76 — Non-current portion of Senior Secured Debenture — 2,611 Total debt $ 76 $ 10,988

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Common Stock are Reserved for Future Issuance	Shares of common stock for future issuance are reserved for as follows (in thousands): September 30, 2018 Warrants outstanding 19,224 Stock options outstanding 434 Options reserved for future issuance under the Company’s 2017 Equity Incentive Plan 381 Shares reserved for future issuance under the Employee Stock Purchase Plan 115 Restricted stock units 13 Total reserved for future issuance 20,167

Warrants to Acquire Shares of_2

Warrants to Acquire Shares of Common Stock (Tables)	9 Months Ended
	Sep. 30, 2018
Warrants and Rights Note Disclosure [Abstract]
Schedule Of Warrant Activity Table	The following is a summary of the Company's warrants to acquire shares of common stock activity for the nine months ended September 30, 2018 (in thousands): Warrant Issuance Outstanding, December 31, 2017 Granted Exercised Canceled/Expired Outstanding, September 30, 2018 Expiration July 2018 Offering — 15,268 — — 15,268 July 2023 Pre-funded July 2018 Offering — 4,675 (2,525 ) — 2,150 July 2023 Series A Convertible Preferred — 1,384 — 1,384 September 2023 2017 Equilibria 316 — — 316 December 2022 Galena February 2017 567 — — (535 ) 32 February 2022 Galena Other 80 — — (6 ) 74 January 2022 963 21,327 (2,525 ) (541 ) 19,224
Fair Value of Warrants is Estimated Using Black-Scholes Option Pricing Model	The fair value of the warrants is estimated using a Black-Scholes pricing model with the following inputs: As of September 30, 2018 Warrant Issuance Outstanding (in thousands) Strike price (per share) Expected term (years) Volatility % Risk-free rate % Series A Convertible Preferred 1,384 $ 2.10 5.01 83.18 % 2.94 % Galena February 2017 32 $ 33.00 3.38 85.39 % 2.25 % Galena Other 74 $ 888.22 2.68 85.96 % 2.32 % As of December 31, 2017 Warrant Issuance Outstanding (in thousands) Strike price (per share) Expected term (years) Volatility % Risk-free rate % Galena February 2017 567 $ 13.00 4.12 79.29 % 2.09 % Galena Other 80 $ 28.40 3.19 74.05 % 2.09 %
Changes in Fair Value of Warrant Liability	The changes in fair value of the warrant liability for the nine months ended September 30, 2018 were as follows (in thousands): Warrant Issuance Warrant liability, December 31, 2017 Fair value of warrants granted Fair value of warrants canceled Adjustment to exercise price of warrants Change in fair value of warrants Warrant liability, September 30, 2018 Series A Convertible Preferred $ — $ 5,039 $ — $ 491 $ (4,558 ) $ 972 Galena February 2017 1,305 — (524 ) — (778 ) 3 Galena Other 4 — — — (4 ) — $ 1,309 $ 5,039 $ (524 ) $ 491 $ (5,340 ) $ 975

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Allocated Stock-based Compensation Expense	The following table summarizes the components of stock-based compensation expense in the condensed consolidated statements of operations for the three and nine months ended September 30, 2018 and 2017 , respectively (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Research and development $ 21 $ 543 $ 55 $ 729 General and administrative 115 724 229 3,047 Total stock-based compensation $ 136 $ 1,267 $ 284 $ 3,776
Assumptions for Option Grants Issued	The Company uses the Black-Scholes option-pricing model and the following assumptions were used to determine the fair value of all its stock options granted during the nine months ended September 30, 2018: Nine Months Ended September 30, 2018 Risk free interest rate 2.73 % Volatility 80.83 % Expected lives (years) 6.20 Expected dividend yield — %
Stock Option Activity	The following table summarizes stock option activity of the Company for the nine months ended September 30, 2018 : Total Number of Shares (In Thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (In Thousands) Outstanding at January 1, 2018 10 $ 1,240.55 1.00 $ — Granted 483 5.24 — Canceled (59 ) 5.24 $ — Outstanding at September 30, 2018 434 $ 34.17 9.26 $ — Options exercisable at September 30, 2018 43 $ 265.35 7.51 $ —

Organization and Description _2

Organization and Description of Business (Narrative) (Details)	Dec. 29, 2017shares	Dec. 28, 2017$ / shares	Sep. 30, 2018$ / sharesshares	Dec. 31, 2017$ / sharesshares
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Common stock, par value (usd per share)			$ 0.0001	$ 0.0001
Common stock, shares outstanding (in shares) | shares	5,766,891		20,501,476	5,766,891
Galena Biopharma, Inc
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Reverse stock split ratio		0.0333
Common stock, par value (usd per share)		$ 0.0001
Private SELLAS Security Holders
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Common stock ownership percentage	67.50%
Private SELLAS Security Holders | Galena Biopharma, Inc
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Common stock conversion ratio	43.9972
Pre-Merger Securityholders
Schedule Of Summary Of Significant Accounting Policies [Line Items]
Common stock ownership percentage	32.50%

Liquidity (Details)

Liquidity (Details) $ / shares in Units, $ in Thousands	Jul. 16, 2018USD ($)$ / sharesshares	May 01, 2018USD ($)	Mar. 09, 2018USD ($)$ / shares	Mar. 07, 2018USD ($)$ / sharesshares	Dec. 29, 2017shares	Sep. 30, 2018USD ($)tranche$ / sharesshares	Dec. 31, 2017USD ($)shares	Sep. 30, 2017USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Warrants issued (in shares) | shares	11,520,000				316,163
Sale of stock, price per share (in usd per share) | $ / shares	$ 2.10
Exercise price (usd per share) | $ / shares	$ 0.0001
Warrant term	5 years				5 years
Sale of stock, consideration received on transaction	$ 21,600
Preferred stock, shares issued (in shares) | shares						0	0
Cash and cash equivalents						$ 9,968	$ 2,319
Restricted cash and cash equivalents						114	10,431
Other receivable						6,600	0
Litigation settlement insurance recovery						474	$ 0	$ 500
Accounts payable and accrued liabilities						11,900
Long-term debt						$ 100
Series A- Convertible Preferred Stock
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceeds from issuance of private placement				$ 10,700
Series A- Convertible Preferred Stock | First Tranche
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceeds from issuance of private placement			$ 6,000
Series A- Convertible Preferred Stock | Second Tranche
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceeds from issuance of private placement		$ 4,700
Common Stock
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sale of stock, number of shares issued in transaction | shares	6,845,000
Warrant
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sale of stock, number of shares issued in transaction | shares	4,675,000
Sale of stock, price per share (in usd per share) | $ / shares	$ 2.0999
Purchase Agreement | Series A Non-voting Convertible
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Warrants issued (in shares) | shares				1,383,631
Warrant term				5 years 6 months
Preferred stock, shares issued (in shares) | shares				10,700
Conversion price (USD per share) | $ / shares						$ 1
Purchase Agreement | Series A- Convertible Preferred Stock
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Conversion price (USD per share) | $ / shares			$ 5.80	$ 6.59
Number of tranches | tranche						2

Basis Of Presentation and Sig_4

Basis Of Presentation and Significant Accounting Policies - Components of Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 24, 2018	May 18, 2018	Dec. 31, 2017	Sep. 30, 2017	Aug. 31, 2017	Dec. 31, 2016	May 10, 2016
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 9,968			$ 2,319
Restricted cash and cash equivalents	114			10,431
Total cash, cash equivalents, restricted cash, and restricted cash equivalents	10,082			12,750	$ 2,369		$ 5,962
Corporate Credit Cards
Cash and Cash Equivalents [Line Items]
Restricted cash and cash equivalents	$ 100			200
Secured Debt
Cash and Cash Equivalents [Line Items]
Restricted cash		$ 8,500
Amendment Agreement | Secured Debt
Cash and Cash Equivalents [Line Items]
Maximum prepayment of principle if demanded						$ 18,500		$ 18,500
Restricted cash			$ 8,500	$ 10,200

Acquisition (Details)

Acquisition (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017
Business Acquisition [Line Items]
Net loss	$ (9,066)	$ (21,690)
Basic net loss per share (usd per share)	$ (1.61)	$ 4.92
Diluted net loss per share (usd per share)	$ (1.61)	$ 4.92
Conversion of convertible notes	$ 5,800	$ 5,800
Goodwill and intangible assets impairment loss	5,200	5,200
Business acquisition, transaction costs	3,300	3,300
Historical Interest Expense
Business Acquisition [Line Items]
Pro forma adjustments to net loss	$ 200	$ 300

Fair Value Measurements (Contin

Fair Value Measurements (Contingent Purchase Price Consideration, Measured at Estimated Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Liabilities:
Warrants potentially settleable in cash	$ 975	$ 1,309
Unobservable Inputs (Level 3)
Liabilities:
Contingent consideration	5,319	1,294
Fair Value, Measurements, Recurring
Assets:
Cash equivalents	6,774	1,662
Restricted cash equivalents		10,245
Total assets measured and recorded at fair value	6,774	11,907
Liabilities:
Warrants potentially settleable in cash	975	1,309
Contingent consideration	5,319	1,294
Total liabilities measured and recorded at fair value	6,294	2,603
Fair Value, Measurements, Recurring | Quoted Prices In Active Markets (Level 1)
Assets:
Cash equivalents	6,774	1,662
Restricted cash equivalents		10,245
Total assets measured and recorded at fair value	6,774	11,907
Liabilities:
Warrants potentially settleable in cash	0	0
Contingent consideration	0	0
Total liabilities measured and recorded at fair value	0	0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Assets:
Cash equivalents	0	0
Restricted cash equivalents		0
Total assets measured and recorded at fair value	0	0
Liabilities:
Warrants potentially settleable in cash	0	0
Contingent consideration	0	0
Total liabilities measured and recorded at fair value	0	0
Fair Value, Measurements, Recurring | Unobservable Inputs (Level 3)
Assets:
Cash equivalents	0	0
Restricted cash equivalents		0
Total assets measured and recorded at fair value	0	0
Liabilities:
Warrants potentially settleable in cash	975	1,309
Contingent consideration	5,319	1,294
Total liabilities measured and recorded at fair value	$ 6,294	$ 2,603

Fair Value Measurements (Reconc

Fair Value Measurements (Reconciliation of Level 3 Liabilities) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Change in fair value of contingent consideration	$ (162)	$ 0	$ (4,025)	$ 0
Unobservable Inputs (Level 3)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance Liabilities			1,294
Change in fair value of contingent consideration			4,025
Ending Balance Liabilities	$ 5,319		$ 5,319
Apthera, Inc.
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Contingent consideration payable, maximum amount					$ 32,000

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Professional fees	$ 2,836	$ 1,744
Compensation and related benefits	808	566
Clinical trial costs	583	51
Value-added tax	158	426
Rebates and returns of former commercial products	22	223
Other	276	191
Accrued expenses and other current liabilities	4,683	3,201
Legal fees	0	$ 1,300
JBG Litigation
Liability for Claims and Claims Adjustment Expense [Line Items]
Legal fees	$ 2,500

Debt (Summary of Debt) (Details

Debt (Summary of Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Current portion of Senior Secured Debenture	$ 76	$ 8,377
Non-current portion of Senior Secured Debenture	0	2,611
Total debt	76	10,988
Secured Debt | Securities Purchase Agreement
Debt Instrument [Line Items]
Current portion of Senior Secured Debenture	0	8,377
Non-current portion of Senior Secured Debenture	0	2,611
Convertible Notes Payable
Debt Instrument [Line Items]
Short-term convertible promissory notes	$ 76	$ 0

Debt (Senior Secured Debenture)

Debt (Senior Secured Debenture) (Details) - USD ($)

Nov. 05, 2018

May 10, 2016

Nov. 14, 2018

Sep. 30, 2018

Sep. 30, 2017

Sep. 30, 2018

Sep. 30, 2017

Dec. 31, 2017

Oct. 16, 2018

Sep. 24, 2018

Jul. 16, 2018

May 18, 2018

Dec. 29, 2017

Aug. 31, 2017

Debt Instrument [Line Items]

Warrants issued (in shares)

11,520,000

316,163

Outstanding principal

$ 10,200,000

Principal redeemed

$ 2,800,000

Debt instrument, redemption, principal amount redeemed, shares

659,529

659,529

Debt amount redeemed, settled in cash

$ 600,000

Decrease in restricted cash

1,800,000

Gain on extinguishment of debt

$ 766,000

$ 0

766,000

$ 0

Secured Debt

Debt Instrument [Line Items]

Fixed coupon rate

9.00%

Restricted cash

$ 8,500,000

Balance of restricted cash over senior secured debenture

$ 1,600,000

Securities Purchase Agreement | Secured Debt

Debt Instrument [Line Items]

Fixed coupon rate

6.375%

Principal amount of debt

$ 25,530,000

Warrants issued (in shares)

3,333

Proceeds from issuance of debt and warrants

$ 23,400,000

Amendment Agreement | Secured Debt

Debt Instrument [Line Items]

Final payment of interest

$ 800,000

800,000

Debt instrument, covenant, compensating cash balance

$ 18,500,000

$ 18,500,000

Restricted cash

$ 10,200,000

$ 8,500,000

Subsequent Event

Debt Instrument [Line Items]

Deposit of restricted cash over senior secured debenture

$ 1,600,000

JGB Action | Subsequent Event

Debt Instrument [Line Items]

Restricted cash

$ 1,600,000

Balance of restricted cash over senior secured debenture

1,600,000

Loss contingency, damages awarded, value

6,600,000

Gain on reimbursement of legal fees

5,000,000

Gain on extinguishment of debt

$ 800,000

$ 800,000

Debt (Convertible Debt) (Detail

Debt (Convertible Debt) (Details) - USD ($)	1 Months Ended	9 Months Ended
	Apr. 30, 2018	Sep. 30, 2018
Debt Instrument [Line Items]
Common stock acquired in exchange for warrants (in shares)		412,667
Convertible Notes Payable | Convertible Promissory Notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 1,000,000
Common stock acquired in exchange for warrants (in shares)		412,667
Debt instrument, interest rate, stated percentage		5.00%
Debt instrument, convertible, conversion price (in USD per share)		$ 7
Warrants and rights outstanding	$ 800,000	$ 100,000
Conversion of units (in shares)	118,644

Legal Proceedings, Commitment_2

Legal Proceedings, Commitments and Contingencies (Details) $ in Thousands

Nov. 05, 2018USD ($)

Oct. 23, 2018counterclaim

May 18, 2018USD ($)counterclaim

Jul. 24, 2017USD ($)

Nov. 14, 2018USD ($)

Oct. 31, 2018USD ($)

Sep. 30, 2018USD ($)

Sep. 30, 2017USD ($)

Sep. 30, 2018USD ($)

Sep. 30, 2017USD ($)

Sep. 24, 2018USD ($)

Dec. 31, 2017USD ($)

Loss Contingencies [Line Items]

Gain on extinguishment of debt

$ 766

$ 0

$ 766

$ 0

JGB (Cayman) Newton Ltd

Loss Contingencies [Line Items]

Legal fees

$ 2,500

Loss contingency, number of counterclaims | counterclaim

7

Pending Litigation | Patel vs Galena biopharma, Inc

Loss Contingencies [Line Items]

Payments for legal settlement

$ 50

Litigation settlement with issuance of common stock

$ 1,250

Secured Debt

Loss Contingencies [Line Items]

Restricted cash

$ 8,500

Secured Debt | Amendment Agreement

Loss Contingencies [Line Items]

Restricted cash

$ 8,500

$ 10,200

Subsequent Event

Loss Contingencies [Line Items]

Litigation settlement insurance recovery

$ 500

Subsequent Event | JGB (Cayman) Newton Ltd

Loss Contingencies [Line Items]

Legal fees

$ 2,500

Restricted cash

$ 1,600

Loss contingency, number of counterclaims | counterclaim

4

Loss contingency, damages awarded, value

6,600

Gain on extinguishment of debt

$ 800

$ 800

Stockholders' Equity (Narrative

Stockholders' Equity (Narrative) (Details) - USD ($)	Jul. 16, 2018	May 01, 2018	Mar. 09, 2018	Mar. 07, 2018	Dec. 29, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	May 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)						5,000,000		5,000,000			5,000,000
Preferred stock, par value (usd per share)						$ 0.0001		$ 0.0001			$ 0.0001
Preferred stock, shares issued (in shares)						0		0			0
Warrants issued (in shares)	11,520,000				316,163
Proceeds from issuance of preferred stock, preference stock, and warrants								$ 9,647,000	$ 0
Shares issued upon conversion (in shares)	3,748,184
Convertible preferred stock converted to other securities	$ 7,871,186
Exercise price (usd per share)	$ 2.10				$ 7.42					$ 6.59
Increase (decrease) in fair value of warrant liability						$ 500,000		491,000	0
Warrant term	5 years				5 years
Deemed dividend arising from the issuance of common stock to Series A convertible preferred stockholders under most favored nation provision						$ 8,654,000	$ 0	$ 8,654,000	$ 0
Common stock, shares authorized (in shares)						350,000,000		350,000,000			350,000,000
Common stock, par value (usd per share)						$ 0.0001		$ 0.0001			$ 0.0001
Sale of stock, price per share (in usd per share)	$ 2.10
Common stock warrant, shares to purchase	1
Exercise price (usd per share)	$ 0.0001
Sale of stock, consideration received on transaction	$ 21,600,000
Purchase Agreement | Private Placement First Closing
Class of Stock [Line Items]
Warrants issued shares (in shares)			774,186
Series A Non-voting Convertible | Purchase Agreement
Class of Stock [Line Items]
Preferred stock, par value (usd per share)				$ 0.0001
Preferred stock, shares issued (in shares)				10,700
Warrants issued (in shares)				1,383,631
Proceeds from issuance of preferred stock, preference stock, and warrants				$ 10,700,000
Shares issued upon conversion (in shares)				1,844,835
Conversion price (USD per share)						$ 1		$ 1
Warrant term				5 years 6 months
Series A- Convertible Preferred Stock | Private Placement First Closing
Class of Stock [Line Items]
Deemed dividend on beneficial conversion feature of convertible preferred stock		$ 2,500,000	$ 2,000,000
Series A- Convertible Preferred Stock | Purchase Agreement
Class of Stock [Line Items]
Conversion price (USD per share)			$ 5.80	$ 6.59
Series A- Convertible Preferred Stock | Purchase Agreement | Private Placement First Closing
Class of Stock [Line Items]
Proceeds from issuance of preferred stock, preference stock, and warrants			$ 6,000,000
Convertible preferred stock issued shares (in shares)			5,987
Series A- Convertible Preferred Stock | Purchase Agreement | Private Placement Second Closing
Class of Stock [Line Items]
Proceeds from issuance of preferred stock, preference stock, and warrants			$ 4,700,000
Convertible preferred stock issued shares (in shares)			4,713
Warrants issued shares (in shares)			609,445
Warrant
Class of Stock [Line Items]
Shares issued upon conversion (in shares)	3,748,184
Sale of stock, number of shares issued in transaction	4,675,000
Sale of stock, price per share (in usd per share)	$ 2.0999
Common Stock
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction	6,845,000

Stockholders' Equity (Common St

Stockholders' Equity (Common Stock are Reserved for Future Issuance) (Details) - shares shares in Thousands	Sep. 30, 2018	Dec. 31, 2017
Equity [Abstract]
Warrants outstanding (in shares)	19,224	963
Stock options outstanding (in shares)	434	10
Options reserved for future issuance under the Company's 2017 Incentive Plan (in shares)	381
Shares reserved for future issuance under the Employee Stock Purchase Plan (in shares)	115
Restricted stock units (in shares)	13
Total reserved for future issuance (in shares)	20,167

Warrants to Acquire Shares of_3

Warrants to Acquire Shares of Common Stock (Schedule of Warrant Activity) (Details) shares in Thousands	9 Months Ended
	Sep. 30, 2018shares
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance (in shares)	963
Granted (in shares)	21,327
Exercised (in shares)	(2,525)
Canceled/Expired (in shares)	(541)
Warrants outstanding , Ending balance (in shares)	19,224
July 2018 Offering
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance (in shares)	0
Granted (in shares)	15,268
Exercised (in shares)	0
Canceled/Expired (in shares)	0
Warrants outstanding , Ending balance (in shares)	15,268
Pre-funded 2018 Offering
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance (in shares)	0
Granted (in shares)	4,675
Exercised (in shares)	(2,525)
Canceled/Expired (in shares)	0
Warrants outstanding , Ending balance (in shares)	2,150
Series A Convertible Preferred
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance (in shares)	0
Granted (in shares)	1,384
Exercised (in shares)	0
Warrants outstanding , Ending balance (in shares)	1,384
2017 Equilibria
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance (in shares)	316
Granted (in shares)	0
Exercised (in shares)	0
Warrants outstanding , Ending balance (in shares)	316
Galena February 2017
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance (in shares)	567
Granted (in shares)	0
Exercised (in shares)	0
Canceled/Expired (in shares)	(535)
Warrants outstanding , Ending balance (in shares)	32
Galena Other
Class of Warrant or Right, Outstanding [Roll Forward]
Warrants outstanding , Beginning balance (in shares)	80
Granted (in shares)	0
Exercised (in shares)	0
Canceled/Expired (in shares)	(6)
Warrants outstanding , Ending balance (in shares)	74

Warrants to Acquire Shares of_4

Warrants to Acquire Shares of Common Stock (Narrative) (Details)	1 Months Ended	9 Months Ended
	Apr. 30, 2018USD ($)shares	Sep. 30, 2018USD ($)$ / sharesshares	Jul. 16, 2018$ / shares	May 31, 2018$ / shares	Dec. 29, 2017$ / shares
Class of Warrant or Right [Line Items]
Shares issued for cancellation of warrants (in shares)		54,613
Surrender and cancellation of warrants (in shares)		121,667
Common stock acquired in exchange for warrants (in shares)		412,667
Fair value of consideration exchanged | $		$ 1,200,000
Exercise price (usd per share) | $ / shares			$ 2.10	$ 6.59	$ 7.42
Series A Convertible Preferred
Class of Warrant or Right [Line Items]
Exercise price (usd per share) | $ / shares		$ 6.59
Convertible Promissory Notes | Convertible Notes Payable
Class of Warrant or Right [Line Items]
Debt instrument, face amount | $		$ 1,000,000
Common stock acquired in exchange for warrants (in shares)		412,667
Warrants and rights outstanding | $	$ 800,000	$ 100,000
Conversion of units (in shares)	118,644
Measurement Input, Price Volatility
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input					0.9010
Measurement Input, Risk Free Interest Rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		0			0.0220
Measurement Input, Expected Dividend Rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		0			0

Warrants to Acquire Shares of_5

Warrants to Acquire Shares of Common Stock (Fair Value of Warrants is Estimated Using Black-Scholes Option Pricing Model) (Details) - $ / shares shares in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	19,224	963
Series A Convertible Preferred
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	1,384	0
Strike price (in usd per share)	$ 2.10
Expected term (years)	5 years 4 days
Volatility %	83.18%
Risk-free rate %	2.94%
Galena February 2017
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	32	567
Strike price (in usd per share)	$ 33	$ 13
Expected term (years)	3 years 4 months 17 days	4 years 1 month 13 days
Volatility %	85.39%	79.29%
Risk-free rate %	2.25%	2.09%
Galena Other
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	74	80
Strike price (in usd per share)	$ 888.22	$ 28.4
Expected term (years)	2 years 8 months 5 days	3 years 2 months 9 days
Volatility %	85.96%	74.05%
Risk-free rate %	2.32%	2.09%

Warrants to Acquire Shares of_6

Warrants to Acquire Shares of Common Stock (Changes in Fair Value of Warrant Liability) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Class of Warrant or Right, Fair Value [Roll Forward]
Warrant liability, Beginning balance	$ 1,309
Fair value of warrants granted	5,039
Fair value of warrants canceled	(524)
Adjustment to exercise price of warrants	491
Change in fair value of warrants	(5,340)
Warrant liability, Ending balance	975
Series A Convertible Preferred
Class of Warrant or Right, Fair Value [Roll Forward]
Warrant liability, Beginning balance	0
Fair value of warrants granted	5,039
Fair value of warrants canceled	0
Adjustment to exercise price of warrants	491
Change in fair value of warrants	(4,558)
Warrant liability, Ending balance	972
Galena February 2017
Class of Warrant or Right, Fair Value [Roll Forward]
Warrant liability, Beginning balance	1,305
Fair value of warrants granted	0
Fair value of warrants canceled	(524)
Adjustment to exercise price of warrants	0
Change in fair value of warrants	(778)
Warrant liability, Ending balance	3
Galena Other
Class of Warrant or Right, Fair Value [Roll Forward]
Warrant liability, Beginning balance	4
Fair value of warrants granted	0
Fair value of warrants canceled	0
Adjustment to exercise price of warrants	0
Change in fair value of warrants	(4)
Warrant liability, Ending balance	$ 0

Warrants to Acquire Shares of_7

Warrants to Acquire Shares of Common Stock (Warrants Classified as Equity) (Details)	Jul. 16, 2018$ / sharesshares	Dec. 29, 2017year$ / sharesshares	Sep. 30, 2018	May 31, 2018$ / shares
Class of Warrant or Right [Line Items]
Warrants issued (in shares) | shares	11,520,000	316,163
Exercise price (usd per share)	$ 2.10	$ 7.42		$ 6.59
Warrant term	5 years	5 years
Fair value of warrants granted, per share		$ 5.60
Measurement Input, Price Volatility
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		0.9010
Measurement Input, Expected Term
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input | year		5
Measurement Input, Risk Free Interest Rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		0.0220	0
Measurement Input, Expected Dividend Rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		0	0

Stock-Based Compensation (Narra

Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	Jan. 01, 2018	Dec. 29, 2017	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, grants in period, net of forfeitures (in shares)			0		0
Weighted average exercise price, granted (USD per share)				$ 3.73
Averages contractual term				10 years
Expected dividend yield				0.00%
Unrecognized compensation cost				$ 1.2
Operating expenses weighted average period				2 years 5 months 16 days
Closing price of the Company's common stock (in USD per share)			$ 1.22	$ 1.22
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, vesting period				3 years
Equity instruments other than options, outstanding, number (in shares)			13,000	13,000		13,000
Equity instruments other than options, outstanding, weighted average grant date fair value (in USD per share)			$ 52.94	$ 52.94		$ 52.94
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term				6 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term				4 years
2017 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)			381,000	381,000
Options expire from date of grant		10 years
Percentage increase in number of shares available for future issuance under stock based awards		4.00%
Number of additional shares authorized (in shares)	805,000
Options, grants in period, net of forfeitures (in shares)						0
2017 Equity Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)		575,000
Incentive Plan 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options assumed in merger (in shares)		10,171

Stock-Based Compensation (Alloc

Stock-Based Compensation (Allocated Stock-based Compensation) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share based compensation expense	$ 136	$ 1,267	$ 284	$ 3,776
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share based compensation expense	21	543	55	729
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share based compensation expense	$ 115	$ 724	$ 229	$ 3,047

Stock-Based Compensation (Assum

Stock-Based Compensation (Assumptions for Option Grants Issued) (Details)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Risk free interest rate	2.73%
Volatility	80.83%
Expected lives (years)	6 years 2 months 12 days
Expected dividend yield	0.00%

Stock-Based Compensation (Stock

Stock-Based Compensation (Stock Option Activity) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	Dec. 31, 2017	Sep. 30, 2018	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, beginning balance (in shares)	10	434	434
Granted (in shares)		483
Canceled (in shares)		(59)
Options outstanding, ending balance (in shares)	10	434
Exercisable (in shares)			43
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted average exercise price, beginning balance (usd per share)		$ 1,240.55
Weighted average exercise price, granted (usd per share)		5.24
Weighted average exercise price, canceled (use per share)		5.24
Weighted average exercise price, ending balance (usd per share)	$ 1,240.55	$ 34.17
Weighted average exercise price, exercisable (usd per share)			$ 265.35
Weighted average remaining contractual term, options exercisable (in years)	1 year	7 years 6 months 4 days
Weighted average remaining contractual term, outstanding (in years)		9 years 3 months 4 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Aggregate Intrinsic Value [Roll Forward]
Stock options activity, aggregate intrinsic value, beginning balance		$ 0
Stock options activity, aggregate intrinsic value, granted		0
Stock options activity, aggregate intrinsic value, canceled		0
Stock options activity, aggregate intrinsic value, ending balance	$ 0	$ 0
Stock options activity, aggregate intrinsic value, exercisable			$ 0