LadRx (LADX) 10-K 16 Mar 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Mar. 16, 2018	Jun. 30, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	CYTRX CORP
Entity Central Index Key	799,698
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 94.5
Entity Common Stock, Shares Outstanding		28,037,501
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017

BALANCE SHEETS

BALANCE SHEETS - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 37,643,404	$ 56,959,485
Receivables	7,529,032	183,703
Prepaid expenses and other current assets	1,914,077	3,434,238
Total current assets	47,086,513	60,577,426
Equipment and furnishings, net	1,042,892	1,959,667
Goodwill	183,780	183,780
Other assets	34,334	48,911
Total assets	48,347,519	62,769,784
Current liabilities:
Accounts payable	4,122,017	6,406,445
Accrued expenses and other current liabilities	8,029,274	3,830,498
Deferred revenue	6,924,353	0
Term loan, net - current	10,599,795	5,481,656
Warrant liabilities	527,025	3,789,391
Total current liabilities	30,202,464	19,507,990
Long term loan, net	0	18,484,510
Total liabilities	30,202,464	37,992,500
Commitment and contingencies
Stockholders' equity (2016 restated to reflect a 1-6 reverse stock split, see Note 1):
Common stock, $0.001 par value, 41,666,667 shares authorized; 28,037,501 and 18,553,817 shares issued and outstanding at December 31, 2017 and 2016, respectively	28,037	18,553
Additional paid-in capital	468,969,445	440,106,726
Accumulated deficit	(450,852,427)	(415,865,995)
Total stockholders' equity	18,145,055	24,777,284
Total liabilities and stockholders' equity	48,347,519	62,769,784
Series A Junior Participating Preferred Stock [Member]
Stockholders' equity (2016 restated to reflect a 1-6 reverse stock split, see Note 1):
Preferred Stock	0	0
Series B Convertible Preferred Shares [Member]
Stockholders' equity (2016 restated to reflect a 1-6 reverse stock split, see Note 1):
Preferred Stock	$ 0	$ 518,000

BALANCE SHEETS (Parenthetical)

BALANCE SHEETS (Parenthetical)	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)$ / sharesshares
Stockholders' equity (2016 restated to reflect a 1-6 reverse stock split, see Note 1):
Reserve stock split	6
Preferred stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	833,334	833,334
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share) | $ / shares	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	41,666,667	41,666,667
Common stock, shares issued (in shares)	28,037,501	18,553,817
Common stock, shares outstanding (in shares)	28,037,501	18,553,817
Series A Junior Participating Preferred Stock [Member]
Stockholders' equity (2016 restated to reflect a 1-6 reverse stock split, see Note 1):
Preferred stock, shares authorized (in shares)	4,167	4,167
Series B Convertible Preferred Shares [Member]
Stockholders' equity (2016 restated to reflect a 1-6 reverse stock split, see Note 1):
Preferred stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01
Preferred stock, stated value | $	$ 1,000	$ 1,000
Preferred stock, shares authorized (in shares)	650	650
Preferred Stock, conversion value (in dollars per share) | $ / shares	$ 2.52	$ 2.52
Preferred stock, shares issued (in shares)	550	550
Preferred stock, shares outstanding (in shares)	0	518

STATEMENTS OF OPERATIONS

STATEMENTS OF OPERATIONS - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue:
Licensing revenue	$ 100,000	$ 200,000	$ 100,000
Expenses:
Research and development	19,840,106	35,930,212	43,395,574
General and administrative	12,502,042	15,990,789	19,664,904
Depreciation and amortization	629,312	536,631	317,649
Total expenses	32,971,460	52,457,632	63,378,127
Loss before other income (expense)	(32,871,460)	(52,257,632)	(63,278,127)
Other income (expense):
Interest income	365,584	255,123	233,958
Interest expense	(3,831,211)	(2,754,677)	0
Other income (expense), net	(16,322)	159,148	20,151
Gain on warrant liabilities	1,367,777	3,827,617	4,437,628
Loss before provision for income taxes	(34,985,632)	(50,770,421)	(58,586,390)
Provision for income taxes	(800)	(800)	(800)
Net loss	$ (34,986,432)	$ (50,771,221)	$ (58,587,190)
Basic and diluted net loss per share (in dollars per share)	$ (1.46)	$ (3.78)	$ (5.82)
Basic and diluted weighted-average shares outstanding (in shares)	24,042,293	13,510,629	10,080,526

STATEMENTS OF STOCKHOLDERS' EQU

STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($)	Preferred Stock [Member]Series B Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2014	$ 0	$ 9,321	$ 377,022,587	$ (306,507,584)	$ (2,612,861)	$ 67,911,463
Balance (in shares) at Dec. 31, 2014	0	9,320,331
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock options/warrants for compensation and services	$ 0	$ 0	7,384,656	0	0	7,384,656
Issuance of stock options/warrants for compensation and services (in shares)	0	0
Common stock issued in connection with a public offering	$ 0	$ 1,744	26,778,324	0	0	26,780,068
Common stock issued in connection with a public offering (in shares)	0	1,744,167
Options and warrants exercised	$ 0	$ 48	589,953	0	0	590,001
Options and warrants exercised (in shares)	0	48,726
Retirement of treasury stock	$ 0	$ (33)	(2,612,828)	0	2,612,861	0
Retirement of treasury stock (in shares)	0	(33,213)
Net loss	$ 0	$ 0	0	(58,587,190)	0	(58,587,190)
Balance at Dec. 31, 2015	$ 0	$ 11,080	409,162,692	(365,094,774)	0	44,078,998
Balance (in shares) at Dec. 31, 2015	0	11,080,011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock options/warrants for compensation and services	$ 0	$ 0	6,735,576	0	0	6,735,576
Issuance of stock options/warrants for compensation and services (in shares)	0	0
Common stock issued in connection with a public offering	$ 550,000	$ 6,685	25,220,572	0	0	25,777,257
Common stock issued in connection with a public offering (in shares)	550	6,685,362
Options and warrants exercised	$ 0	$ 64	744,087	0	0	744,151
Options and warrants exercised (in shares)	0	64,393
Warrants issued in connection with a public offering	$ 0	$ 0	(6,923,551)	0	0	(6,923,551)
Preferred stock conversion	$ (32,000)	$ 76	31,924	0	0	0
Preferred stock conversion (in shares)	(32)	76,191
Issuance of restricted stock grant	$ 0	$ 388	1,937	0	0	2,325
Issuance of restricted stock grant (in shares)	0	387,597
Warrants issued in connection with term loan	$ 0	$ 0	633,749	0	0	633,749
Beneficial conversion feature - Series B preferred stock	(314,286)	0	314,286	0	0	0
Series B preferred stock deemed dividend	314,286	0	(314,286)	0	0	0
Class action settlement share issuance	$ 0	$ 260	4,499,740	0	0	4,500,000
Class action settlement share issuance (in shares)	0	260,263
Net loss	$ 0	$ 0	0	(50,771,221)	0	(50,771,221)
Balance at Dec. 31, 2016	$ 518,000	$ 18,553	440,106,726	(415,865,995)	0	$ 24,777,284
Balance (in shares) at Dec. 31, 2016	518	18,553,817				18,553,817
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock options/warrants for compensation and services	$ 0	$ 0	3,344,520	0	0	$ 3,344,520
Issuance of stock options/warrants for compensation and services (in shares)	0	0
Common stock issued in connection with a public offering	$ 0	$ 5,000	13,946,218	0	0	13,951,218
Common stock issued in connection with a public offering (in shares)	0	5,000,000
Options and warrants exercised	$ 0	$ 881	3,012,779	0	0	$ 3,013,660
Options and warrants exercised (in shares)	0	880,788				900,000
Preferred stock conversion	$ (518,000)	$ 1,233	516,767	0	0	$ 0
Preferred stock conversion (in shares)	(518)	1,233,334
Issuance of restricted stock grant	$ 0	$ 388	0	0	0	388
Issuance of restricted stock grant (in shares)	0	387,597
Warrants repriced to term loan lender	$ 0	$ 0	76,549	0	0	76,549
Shares issued in connection with licensing sale	$ 0	$ 1,970	6,073,677	0	0	6,075,647
Shares issued in connection with licensing sale (in shares)	0	1,969,697
1 - 6 reverse stock split fractional shares	$ 0	$ 12	(12)	0	0	$ 0
1 - 6 reverse stock split fractional shares (in shares)	0	12,268				12,268
Warrant liability exercises	$ 0	$ 0	1,894,589	0	0	$ 1,894,589
Banking fee on warrant exercises	0	0	(2,368)	0	0	(2,368)
Net loss	0	0	0	(34,986,432)	0	(34,986,432)
Balance at Dec. 31, 2017	$ 0	$ 28,037	$ 468,969,445	$ (450,852,427)	$ 0	$ 18,145,055
Balance (in shares) at Dec. 31, 2017	0	28,037,501				28,037,501

STATEMENTS OF CASH FLOWS

STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net loss	$ (34,986,432)	$ (50,771,221)	$ (58,587,190)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	629,312	536,631	317,649
Loss on retirement of equipment and furnishings	424,049	12,276	2,614
Gain on warrant liabilities	(1,367,777)	(3,827,617)	(4,437,628)
Amortization of loan cost and discount	1,923,816	587,837	0
Stock-based compensation expense	3,344,520	6,735,576	7,384,656
Non-cash litigation settlement due in common stock	0	0	4,500,000
Changes in assets and liabilities:
Receivable	(7,344,941)	4,412,097	(2,574,182)
Interest receivable	0	28,130	76,497
Prepaid expenses and other current assets	1,534,738	(28,569)	1,118,931
Accounts payable	(2,286,416)	(1,672,631)	916,919
Deferred revenue	6,924,353	0	0
Accrued expenses and other current liabilities	4,007,210	(5,862,861)	3,699,287
Net cash used in operating activities	(27,197,568)	(49,850,352)	(47,582,447)
Cash flows from investing activities:
Proceeds from matured short-term investments	0	35,035,420	76,544,319
Purchase of short-term investments	0	0	(65,958,146)
Purchases of equipment and furnishings	(134,598)	(1,020,441)	(331,328)
Net cash provided by (used in) investing activities	(134,598)	34,014,979	10,254,845
Cash flows from financing activities:
Proceeds from common stock issued in public offering, net of fees	13,951,218	25,777,257	26,780,068
Proceeds from term loan, net	0	24,012,078	0
Proceeds from sale of common shares and warrants related to NantCell	6,075,647	0	0
Loan amendment fee payment	(200,000)	0	0
Term loan principal repayment	(15,013,638)	0	0
Net proceeds from exercise of stock options and warrants	3,202,858	744,151	590,001
Net cash provided by financing activities	8,016,085	50,533,486	27,370,069
Net increase (decrease) in cash and cash equivalents	(19,316,081)	34,698,113	(9,957,533)
Cash and cash equivalents at beginning of year	56,959,485	22,261,372	32,218,905
Cash and cash equivalents at end of year	37,643,404	56,959,485	22,261,372
Supplemental disclosures of non-cash financing/investing activities:
Warrant liability exercises	1,894,589	0	3
Warrants repriced in connection with the sale of licenses	76,549	0	0
Receivable from issuance of restricted stock	388	2,325	0
Equipment and furnishings purchased but not paid	1,988	20,452	485,743
Retirement of treasury stock	0	0	2,612,861
Warrants issued in connection with the term loan	0	633,749	0
1 - 6 reverse stock split	12	4,500,000	0
Series B Preferred stock beneficial conversion feature and deemed dividend	0	314,286	0
Warrants issued/amended in connection with the public offering	0	6,923,551	0
Series B Preferred stock conversion	1,233	457	0
Supplemental disclosure of Cash Flow Information:
Cash paid during the year for income taxes	800	800	800
Cash paid during the year for interest	$ 2,025,468	$ 1,959,375	$ 0

Nature of Business

Nature of Business	12 Months Ended
	Dec. 31, 2017
Nature of Business [Abstract]
Nature of Business	1. Nature of Business CytRx Corporation ("CytRx" or "the Company") is a biopharmaceutical research and development company specializing in oncology. Our focus is on the discovery, research and clinical development of novel anti-cancer drug candidates that employ novel linker technologies to enhance the accumulation and release of cytotoxic anti-cancer agents at the tumor. CytRx has an active drug discovery and research operation at its laboratory facilities in Freiburg, Germany. The LADR™ (Linker Activated Drug Release) technology platform is a discovery engine combining CytRx's expertise in linker chemistry and albumin biology to create a pipeline of anti-cancer molecules that will avoid unacceptable systemic toxicity while delivering highly potent agents directly to the tumor. The Company has created a "toolbox" of linker technologies that have the ability to significantly increase the therapeutic index of ultra-high potency drugs (10-1,000 times more potent than traditional chemotherapies) by controlling the release of the drug payloads and improving drug-like properties. After infusion, these ultra-high potency drug conjugates bind to circulating albumin for transport of the drug to the tumor. Subsequently, due to specific conditions within the tumor, the linkers are cleaved and release the anti-cancer drug payload. CytRx's current efforts are focused on two classes of ultra-high potency drug conjugates. The Company's strategy across these programs is to generate additional pre-clinical data that will allow them to make informed decisions regarding the selection of one or both programs for moving into human clinical trials either independently or on a partnered basis. During 2017, CytRx's discovery laboratory synthesized and tested over 75 rationally designed drug conjugates with highly potent cytotoxic payloads, and two distinct classes of compounds have been created. To date, four lead candidates have been selected based on in vitro On July 27, 2017, CytRx entered into an exclusive worldwide license with NantCell, Inc. ("NantCell"), granting to NantCell the exclusive rights to develop, manufacture and commercialize aldoxorubicin in all indications, and it is no longer directly working on development of aldoxorubicin. As part of the license, NantCell made a strategic investment of $13 million in CytRx common stock at $6.60 per share (adjusted to reflect its 2017 reverse stock split), a premium of 92% to the market price on that date. CytRx also issued NantCell a warrant to purchase up to 500,000 shares of common stock at $6.60 over the following 18 months. The Company is entitled to receive up to an aggregate of $343 million in potential milestone payments, contingent upon achievement of certain regulatory approvals and commercial milestones. CytRx is also entitled to receive ascending double-digit royalties for net sales for soft tissue sarcomas and mid to high single digit royalties for other indications. Aldoxorubicin is a conjugate of the commonly prescribed chemotherapeutic agent doxorubicin that binds to circulating albumin in the bloodstream and is believed to concentrate the drug at the site of the tumor. Aldoxorubicin, the Company's lead clinical candidate, has been tested in over 600 patients with various types of cancer. Specifically, it is comprised of (6-maleimidocaproyl) hydrazine, an acid-sensitive molecule that is conjugated to doxorubicin. The initial indication for aldoxorubicin is for patients with advanced soft tissue sarcomas (STS). Aldoxorubicin has received Orphan Drug Designation (ODD) by the U.S. FDA for the treatment of STS. ODD provides several benefits including seven years of market exclusivity after approval, certain R&D related tax credits, and protocol assistance by the FDA. European regulators granted aldoxorubicin Orphan designation for STS which confers ten years of market exclusivity among other benefits. In the first quarter of 2018, CytRx announced that NantCell was expanding aldoxorubicin' s use by combining it with immunotherapies and cell based treatments, specifically in metastatic pancreatic cancer and in advanced squamous cell carcinoma of the head and neck or non-small cell lung cancer. Currently, the Company's only research and development activities are at its laboratory facilities in Freiburg, Germany. For this reason and others, its operating expenses are expected to be significantly lower in the near future. Therefore, period to period comparisons should not be relied upon as predictive of the results in future periods. At December 31, 2017, the Company had cash and cash equivalents of approximately $37.6 million. Under the terms of the loan agreement, however, the Company is required to maintain cash equal to a minimum of the greater of three months projected cash burn or $10 million. Management believes that its current resources will be sufficient to fund its operations for the foreseeable future. This estimate is based, in part, upon the Company's currently projected expenditures for 2018 and the first three months of 2019 of approximately $27.8 million (unaudited) , Effective November 1, 2017, the Company completed a 1-for-6 reverse stock split of the Company's outstanding shares of common and preferred stock, reduced its authorized shares of both common and preferred stock by one-sixth; no change was made to the per-share par value of the common stock. All share and per share amounts in the accompanying financial statements have been adjusted to reflect the reverse stock split as if it had occurred at the beginning of the earliest period presented.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation Revenue Recognition Since 2011, the Company has followed the Financial Accounting Standards Board ("FASB") Accounting Standards Codifications ("ASC") ASC 605-25, Revenue Recognition – Multiple-Element Arrangements Other Income (Expense) Cash Equivalents Equipment and Furnishings Fair Value Measurements Level 1 – quoted prices in active markets for identical assets or liabilities. Level 2 – other significant observable inputs for the assets or liabilities through corroboration with market data at the measurement date. Level 3 – significant unobservable inputs that reflect management's best estimate of what market participants would use to price the assets or liabilities at the measurement date. The following table summarizes fair value measurements by level at December 31, 2017 for assets and liabilities measured at fair value on a recurring basis: (In thousands) Level I Level II Level III Total Cash equivalents $ 35,834 $ — $ — $ 35,834 Warrant liabilities — — (527 ) (527 ) The following table summarizes fair value measurements by level at December 31, 2016 for assets and liabilities measured at fair value on a recurring basis: (In thousands) Level I Level II Level III Total Cash equivalents $ 56,276 $ — $ — $ 56,276 Warrant liabilities — — (3,789 ) (3,789 ) There were no transfers between Levels I, II and III during 2017 or 2016. The changes in carrying amounts of the warrant liability for the years ended December 31, 2017 and 2016 were as follows: (In thousands) 2017 2016 Beginning balance $ 3,789 $ 693 Issued — 6,933 Exercised (1,895 ) (9 ) Net changes in valuation (1,367 ) (3,828 ) Ending balance $ 527 $ 3,789 Liabilities measured at fair market value on a recurring basis include warrant liabilities resulting from recent debt and equity financing. In accordance with ASC 815-40, Derivatives and Hedging – Contracts in Entity's Own Equity the warrant liabilities are being marked to fair value each quarter-end until they are completely settled. The warrants are valued using the Black-Scholes method, using assumptions consistent with the Company's application of ASC 505-50, Equity-Based Payments to Non-Employees ("ASC 505-50"). See Warrant Liabilities below. The Company considers carrying amounts of accounts receivable, accounts payable, accrued expenses and term loan, net to approximate fair value due to the short-term nature of these financial instruments. Patents and Patent Application Costs Net Income (Loss) Per Common Share Warrant Liabilities Stock-based Compensation For stock options and stock warrants paid in consideration of services rendered by non-employees, the Company recognizes compensation expense in accordance with the requirements of ASC 505-50 , Equity , Research and Development Expenses Clinical Trial Expenses Income Taxes Income Taxes, ("ASC 740" On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (the 2017 Tax Act) was enacted reducing the corporate tax rate from 35% to 21% which is effective on January 1, 2018. The carrying value of the Company's deferred tax assets is also determined by the enacted U.S. corporate income tax rate. Consequently, any changes in the U.S. corporate income tax rate have impacted the carrying value of the Company's deferred tax assets. Under the new corporate income tax rate of 21%, deferred income taxes decreased but there is a corresponding decrease to the valuation allowance. Therefore, the 2017 Tax Act is expected to have no impact on the Company's 2017 earnings. In accordance with Staff Accounting Bulletin No. 118, as of December 31, 2017, the Company has not completed its accounting for the tax effects of the enactment of the 2017 Tax Act; however, the Company has made a reasonable estimate of the effects on its existing deferred tax balances. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained upon examination by the taxing authorities based on the technical merits of the position. The Company's policy is to recognize any interest and penalties related to unrecognized tax benefits as a component of income tax expenses. Concentrations of Risks Use of Estimates Recent Accounting Pronouncements In August 2016, the Financial Accounting Standards Board issued ASU No. 2016-15 "Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the Emerging Issues Task Force)." The objective of ASU No. 2016-15 is to provide specific guidance on eight cash flow classification issues and how to reduce diversity in how certain cash receipts and cash payments are presented and classified in the statement of cash flows under Topic 230, Statement of Cash Flows, and other Topics. The amendments in this update are effective for public business entities for fiscal years beginning after December 15, 2017 and interim periods within those fiscal years. The Company is still in the process of determining the impact that the implementation of ASU 2016-15 will have on its financial statements. In March 2016, the FASB issued Accounting Standards Update 2016-09, Compensation—Stock Compensation In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)," which requires companies to recognize all leases as assets and liabilities on the consolidated balance sheet. This ASU retains a distinction between finance leases and operating leases, and the classification criteria for distinguishing between finance leases and operating leases are substantially similar to the classification criteria for distinguishing between capital leases and operating leases in the current accounting literature. The result of retaining a distinction between finance leases and operating leases is that under the lessee accounting model in Topic 842, the effect of leases in a statement of operations and a statement of cash flows is largely unchanged from previous GAAP. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Earlier adoption is permitted. Although the Company has not finalized its process of evaluating the impact of adoption of the ASU on its financial statements, the Company expects there will not be a material increase to assets and liabilities on the Company's balance sheet for leases currently classified as operating leases. In January 2016, the FASB issued ASU No. 2016-01 " Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. In November 2015, the FASB issued ASU No. 2015-17 "Income Taxes: Balance Sheet Classification of Deferred Taxes." In May 2014, the FASB issued Accounting Standards Update No. 2014-09 (Topic 606) " Revenue from Contracts with Customers Revenue Recognition currently assessing the method of adoption and the impact this new guidance will have on its financial statements. The Company expects to adopt these standards using the modified retrospective method. The timing of revenue recognition for variable consideration under our licensing and collaboration agreements may be different as a result of this new guidance. The Company is reviewing its licensing agreement for variable consideration, and if any such consideration exists, whether it should be estimated and recognized earlier than under the current revenue guidance. In August 2015, the FASB issued ASU No. 2015-14, "Revenue from Contracts with Customers" ("ASU 2015-14") which deferred the effective date by one year to December 15, 2017 for interim and annual reporting periods beginning after that date and allows for adoption using a full retrospective method, or a modified retrospective method. The Company will adopt the new standard in its first quarter 2018 using the modified retrospective method and is currently in the process of evaluating the impact of the adoption of this standard on its financial statements.

Foreign Currency Remeasurement

Foreign Currency Remeasurement	12 Months Ended
	Dec. 31, 2017
Foreign Currency Remeasurement [Abstract]
Foreign Currency Remeasurement	3. Foreign Currency Remeasurement The U.S. dollar has been determined to be the functional currency for the net assets of the Company's laboratory in Freiburg, Germany. The transactions are recorded in the local currencies and are remeasured at each reporting date using the historical rates for nonmonetary assets and liabilities and current exchange rates for monetary assets and liabilities at the balance sheet date. Exchange gains and losses from the remeasurement of monetary assets and liabilities are recognized in other income (loss). The Company recognized a loss of approximately $23,000, $18,000 and $6,000 for the years ended December 31, 2017, 2016 and 2015, respectively.

Receivables

Receivables	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Receivables	4. Receivables At December 31, 2017, the Company had a receivable of $7.5 million as compared to $0.2 million at December 31, 2016, primarily related to amounts recoverable from its insurance carrier, associated with ongoing legal proceedings. Of this amount, approximately $1.7 million and $0.2 million relate to recoverable legal costs and approximately $5.8 million and $0 relate to recoverable legal settlements accrued by the Company as of December 31, 2017 and 2016, respectively (See Note 11). Due to the likelihood of the collectability of the accounts receivable, no allowance was recorded.

Prepaid and Other Assets

Prepaid and Other Assets	12 Months Ended
	Dec. 31, 2017
Prepaid and Other Assets [Abstract]
Prepaid and Other Assets	5. Prepaid and Other Assets At December 31, 2017 and 2016, the Company had $1.9 million and $3.4 million, respectively, of prepaid and other current assets, which consist primarily of deposits on contracts for research and development, prepaid insurance and leases for its facility.

Equipment and Furnishings

Equipment and Furnishings	12 Months Ended
	Dec. 31, 2017
Equipment and Furnishings [Abstract]
Equipment and Furnishings	6. Equipment and Furnishings Equipment and furnishings at December 31, 2017 and 2016 consist of the following (in thousands): 2017 2016 Equipment and furnishings $ 2,212 $ 2,811 Less — accumulated depreciation (1,169 ) (851 ) Equipment and furnishings, net $ 1,043 $ 1,960 Depreciation and amortization expense for the years ended December 31, 2017, 2016 and 2015 were $629,312, $536,631 and $317,649, respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2017
Accrued Expenses and Other Current Liabilities [Abstract]
Accrued Expenses and Other Current Liabilities	7. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities at December 31, 2017 and 2016 are summarized below (in thousands) 2017 2016 Professional fees $ 209 $ 193 Research and development costs 223 2,208 Litigation settlement 6,450 700 Wages, bonuses and employee benefits 396 487 Royalties 626 — Other 125 242 Total $ 8,029 $ 3,830

Deferred Revenues

Deferred Revenues	12 Months Ended
	Dec. 31, 2017
Deferred Revenues [Abstract]
Deferred Revenues	8. Deferred Revenues We primarily generate revenue through licensing arrangements of our intellectual property. The Company recognizes revenue when amounts are realized or realizable and earned. Revenue is considered realizable and earned when the following criteria are met: (1) persuasive evidence of an arrangement exists; (2) delivery has occurred or services have been rendered; (3) the price is fixed or determinable; and (4) collection of the amounts due are reasonably assured. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company's balance sheets. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as current liabilities. Deferred revenue represents amounts received prior to revenue recognition. On October 3, 2017, CytRx entered into a Reimbursement Agreement with NantCell, Inc. whereby the Company agreed to reimburse them for payment obligations under certain of the contracts under the NantCell licensing agreement up to a maximum of $4.2 million plus one half of any amounts in excess thereof. Once all conditions of the agreement are met and no contingencies remain outstanding, the revenue will be recognized as licensing fee revenue. CytRx recognized $6.9 million of deferred revenue from the NantCell licensing agreement and anticipates recording this as revenues in 2018, once the Company's cost reimbursement obligations are met.

Term Loan

Term Loan	12 Months Ended
	Dec. 31, 2017
Term Loan [Abstract]
Term Loan	9. Term Loan On February 5, 2016, the Company entered into a loan and security agreement with Hercules Technology Growth Capital, Inc. ("HTGC"), as administrative agent and lender, and Hercules Technology III, L.P., as lender, pursuant to which the lenders made long-term loans to the Company on February 8, 2016 in the aggregate principal amount of $25 million. The Term Loans bear interest at the daily variable rate per annum equal to 6.0% plus the prime rate, or 10.5%, whichever is greater. CytRx was required to make interest-only payments on the Term Loans through February 28, 2017, and beginning on March 1, 2017 blended equal monthly installments of principal amortization and accrued interest until the maturity date of the Term Loans on February 1, 2020. Under the terms of the loan, CytRx is required to maintain a minimum cash balance equal to the greater of (i) $10 million or (ii) forward three months projected cash burn. As security under their obligations, the Company issued to the lenders warrants to purchase a total of 105,691 shares of its common stock at an exercise price of $12.30. These warrants are classified as equity warrants with a fair value of $633,749. All outstanding principal and accrued interest on the term loans will be due and payable in full on the maturity date of February 1, 2020. On July 28, 2017, CytRx entered into a First Amendment to Loan and Security Agreement with Hercules to amend its existing long-term loan facility (the "Loan Agreement"). The amendment provided for payment, on July 28, 2017, of $5.0 million in outstanding principal and unpaid interest due under the Loan Agreement, plus a $100,000 prepayment charge, and for repayment, on or prior to September 30, 2017, of an additional $5.0 million outstanding principal and unpaid interest due under the Loan Agreement, plus a second $100,000 prepayment charge. CytRx also agreed to an updated schedule of monthly payments and a new maturity date of August 1, 2018. Pursuant to the amendment, a portion of the warrants (representing 80% of the total number of shares issuable upon exercise of the warrants) was amended to change the exercise price of that portion of the warrants from $12.30 per share to $4.62 per share, which was calculated based upon the 30-day volume-weighted average price of our common stock over the 30-day period beginning 15 days before the July 28, 2017 announcement of the NantCell license transaction. CytRx evaluated the amended debt agreement under ASC 470 and determined it to be a modification and that in accordance with accounting guidance for debt modifications, the incremental fair value of the repriced warrants of $77,000 and the $200,000 fee paid to the lender was recorded as additional loan discount to be recognized using the interest method over the remaining life of the loan. The payment schedule was changed, and the loan will mature in 2018. As security for the Company's obligations under the loan and securities agreement, the Company granted HTGC, as administrative agent, a security interest in substantially all of its existing and after-acquired assets except for its intellectual property and certain other excluded assets. December 31, 2017 December 31, 2016 Term Loan Principal – Current $ 9,986,362 $ 6,214,057 End Fee Payable 1,771,250 — Issuance Cost/Loan Discount – Current (1,157,817 ) (732,401 ) Term Loan, Net – Current $ 10,599,795 $ 5,481,656 Long Term Loan Principal $ — $ 18,785,943 End Fee Payable — 1,771,250 Long Term Loan Discount/Issuance Cost — (2,072,683 ) Long Term Loan, Net $ — $ 18,484,510

Warrant Liabilities

Warrant Liabilities	12 Months Ended
	Dec. 31, 2017
Warrant Liabilities [Abstract]
Warrant Liabilities	10. Warrant Liabilities Warrants issued in connection with the Company's July 2016 equity public offering and modified in the Company's December 2016 equity public offering are classified as liabilities as opposed to equity due to their settlement terms. These warrants are non-cash liabilities and the Company is not required to expend any cash to settle these liabilities. The fair value of these warrants were recorded on the balance sheet at issuance and the warrants were marked to fair value at each financial reporting period, with changes in the fair value recorded as a gain or loss in the statement of operations. The fair value of the warrants is determined using the Black-Scholes option pricing model, which requires the use of significant judgment and estimates for the inputs used in the model. The warrants issued in connection with the Company's August 2011 equity public offering expired in August 2016. The following reflects the weighted-average assumptions for each of the periods indicated: Year Ended December 31, 2017 2016 2015 Risk-free interest rate 1.53 % 0.90 % 0.57 % Expected dividend yield 0 % 0 % 0 % Expected lives 0.55 1.23 0.59 Expected volatility 96.7 % 119.1 % 61.7 % Number of warrants classified as liabilities 2,834,246 4,752,512 1,061,976 Gain on warrant liabilities $ 1,367,777 $ 3,827,617 $ 4,437,628 The dividend yield assumption of zero is based upon the fact the Company has never paid cash dividends and presently has no intention of paying cash dividends. The risk-free interest rate used for each grant is equal to the U.S. Treasury rates in effect at the time of the grant for instruments with a similar expected life. The expected lives are based on the remaining contractual lives of the related warrants at the valuation date. The Company's computation of expected volatility is based on the historical daily volatility of its publicly traded stock. In 2017, 1.2 million warrants expired, and 0.9 million warrants were exercised resulting in the issuance of 0.9 million shares of the Company's common stock. In 2016, 4.8 million warrants in connection with the July 2016 equity offering were issued.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies Commitments The Company acquires assets still in development and enters into research and development arrangements with third parties that often require milestone and royalty payments to the third-party contingent upon the occurrence of certain future events linked to the success of the asset in development. Milestone payments may be required, up to an aggregate of $7.5 million, contingent upon the successful achievement of an important point in the development life-cycle of the pharmaceutical product (e.g., approval of the product for marketing by a regulatory agency). If required, CytRx may also have to make royalty payments, based upon a percentage of the sales of the pharmaceutical product. In respect of aldoxorubicin, it agreed to pay up to a maximum amount of approximately $18.3 million, payable in shares of its common stock, in the event that regulatory approval for marketing is obtained. These arrangements may be material individually, and in the unlikely event that milestones for multiple products covered by these arrangements were reached in the same period, the aggregate charge to expense could be material to the results of operations in any one period. In addition, these arrangements often give CytRx the discretion to unilaterally terminate development of the product, which would allow CytRx to avoid making the contingent payments; however, CytRx is unlikely to cease development if the compound successfully achieves clinical testing objectives. CytRx's current contractual obligations that will require future cash payments are as follows (in thousands): Operating Leases (1) Employment Agreements (2) Research and Development (3) Total 2018 $ 373 $ 1,678 $ 1,000 $ 3,051 2019 278 1,057 — 1,335 2020 59 1,057 — 1,116 2021 — 1,057 — 1,057 2022 — — — — Thereafter — — — — Total $ 710 $ 4,849 $ 1,000 $ 6,559 ____________ (1) Operating leases are primarily facility lease related obligations, as well as equipment lease obligations with third party vendors. The Company recognized rent expenses of $420,106, $358,247, and $351,075 in 2017, 2016 and 2015, respectively. (2) Employment agreements include management contracts which have been revised from time to time. The employment agreement for the Company's executive officers provide for minimum salaries, which are adjusted annually at the discretion of the Company's Compensation Committee, and in some cases provide for minimum annual bonuses and employee benefits, as well. New employment agreements for the Company's other executive officers are usually entered into annually or biennially. (3) Research and development obligations relate primarily to the Reimbursement Agreement with NantCell. All of these purchase obligations are cancelable. Contingencies The Company applies the disclosure provisions of ASC 460, Guarantees ("ASC 460") to its agreements that contain guarantees or indemnities by the Company. The Company provides (i) indemnifications of varying scope and size to certain investors and other parties for certain losses suffered or incurred by the indemnified party in connection with various types of third-party claims; and (ii) indemnifications of varying scope and size to officers and directors against third party claims arising from the services they provide to the Company. Shareholder Derivative Actions in Delaware Niedermeyer et al. v. Kriegsman et al. Taylor v. Kriegsman Niedermeyer et al. Class Action in California. Crihfield v. CytRx Corp., et al. Dorce v. CytRx Corp. In re: CytRx Corporation Securities Litigation Shareholder Derivative Action in Delaware (Zyontz). Zyontz v. Kriegsman et al., Shareholder Derivative Action in Delaware (Patterson). Patterson v. Kriegsman et al., The Company intends to vigorously defend against the foregoing complaints. CytRx has directors' and officers' liability insurance, which will be utilized in the defense of these matters. The liability insurance may not cover all of the future liabilities the Company may incur in connection with the foregoing matters. The Company evaluates developments in legal proceedings and other matters on a quarterly basis. The Company records accruals for loss contingencies to the extent that the Company concludes that it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. The Company has accrued $6.5 million of litigation settlements related to legal actions.

Equity Transactions

Equity Transactions	12 Months Ended
	Dec. 31, 2017
Equity Transactions [Abstract]
Equity Transactions	12. Equity Transactions As of December 31, 2017, the Company has reserved approximately 1.2 million of its authorized but unissued shares of common stock for future issuance pursuant to its employee stock option plans issued to employees and consultants. In December 2017, the Company issued an additional 12,268 fractional shares of its common stock as a result of is 1 to 6 reverse stock split and issued 387,597 shares in restricted common stock (see Note 13). In the second and third quarters of 2017, a total of 880,788 shares of the Company's common stock were issued from the exercise of warrants and options. On July 27, 2017, the Company issued 1,969,697 shares of its common stock and 500,000 warrants to purchase common stock as part of an exclusive licensing agreement granted to NantCell, Inc. On May 2, 2017, the Company issued 5 million of its common stock in a public offering. In the first quarter of 2017, the Company converted 518 shares of its Series B preferred stock in exchange for 1,233,334 shares of its common stock. In 2016, the Company issued 55,000 shares of its common stock resulting from the exercise of employee stock options and issued 387,597 shares in restricted common stock. On December 16, 2016, the Company issued 1,923,457 shares of its common stock and 550 convertible preferred shares at a stated value of $1,000, and repriced 3,232,981 warrants from the July 2016 financing, from $4.20 to $3.06 per common stock, along with extending their term through July 2018, all in respect of a public offering. As a result of the Series B conversion price of $2.52 being less than the common stock price at the closing date, a beneficial conversion feature was recognized in the amount of $0.3 million. Since the preferred stock was immediately convertible, the entire beneficial conversion feature was recognized as a deemed dividend on December 16, 2016. In December 2016, 32 preferred shares were converted at their conversion rate of $2.52 in exchange for 76,191 common shares. On July 20, 2016, the Company issued 4,761,905 shares of its common stock and one-year warrants to purchase an equal number of shares of its common stock in a public offering. On October 26, 2015, the Company retired 33,213 shares of its treasury stock at cost ($2.6 million). On July 24, 2015, the Company issued 1,744,167 shares of common stock in a public offering.

Stock Options and Equity-Classi

Stock Options and Equity-Classified Warrants	12 Months Ended
	Dec. 31, 2017
Stock Options and Equity-Classified Warrants [Abstract]
Stock Options and Equity-Classified Warrants	13. Stock Options and Equity-Classified Warrants Stock Options The Company has a 2000 Long-Term Incentive Plan under which 233,334 shares of common stock were originally reserved for issuance. As of December 31, 2017, there were 44,371shares subject to outstanding stock options. This plan expired on August 6, 2010, and thus no further shares are available for future grant under this plan. The Company also has a 2008 Stock Incentive Plan under which 5 million shares of common stock are reserved for issuance. As of December 31, 2017, there were 2.8 million shares subject to outstanding stock options and 0.8 million shares outstanding related to restricted stock grants issued from the 2008 Plan and 1.2 million shares available for future grant under this plan. The Company follows the provisions of ASC 718, Compensation-Stock Compensation, The fair value of the stock options at the date of grant was estimated using the Black-Scholes option-pricing model, based on the following assumptions: 2017 2016 2015 Risk-free interest rate 2.04% - 2.35 % 1.20% - 2.26 % 1.74% - 2.12 % Expected volatility 86% - 92 % 74% - 88 % 74% - 85 % Expected lives (years) 6 - 10 6 - 10 6 - 10 Expected dividend yield 0.00 % 0.00 % 0.00 % The Company's computation of expected volatility is based on the historical daily volatility of its publicly traded stock. For option grants issued during years ended December 31, 2017, 2016 and 2015, the Company used a calculated volatility for each grant. The Company lacks adequate information about the exercise behavior at this time and has determined the expected term assumption under the simplified method provided for under ASC 718, which averages the contractual term of the Company's options of ten years with the average vesting term of three years for an average of six years. The dividend yield assumption of zero is based upon the fact the Company has never paid cash dividends and presently has no intention of paying cash dividends. The risk-free interest rate used for each grant is equal to the U.S. Treasury rates in effect at the time of the grant for instruments with a similar expected life. Based on historical experience, for each of the two years ended December 31, 2016 and 2015, the Company has estimated an annualized forfeiture rate of 10% for options granted to its employees, 2% for options granted to senior management and 0% for options granted to directors. Compensation costs will be adjusted for future changes in estimated forfeitures. The Company will record additional expense if the actual forfeitures are lower than estimated and will record a recovery of prior expense if the actual forfeiture rates are higher than estimated. On January 1, 2017, the Company adopted ASU 2016-09 and made a policy election to recognize forfeitures as they occur. The adoption of ASU 2016-09 did not have a material impact to the Company's financial condition or results of operations. No amounts relating to stock-based compensation have been capitalized. No amounts relating to employee stock-based compensation have been capitalized. At December 31, 2017, there remained approximately $1.8 million of unrecognized compensation expense related to unvested stock options granted to current employees and directors, to be recognized as expense over a weighted-average period of 1.15 years. Presented below is the Company's stock option activity for employees and directors: Stock Options Weighted Average Exercise Price 2017 2016 2015 2017 2016 2015 Outstanding — beginning of year 2,813,280 2,263,977 1,559,765 $ 14.14 $ 18.66 $ 16.98 Granted 591,369 809,500 765,000 1.87 3.54 15.66 Exercised (19,213 ) (55,000 ) (47,857 ) 2.58 12.84 12.30 Forfeited (874,210 ) (196,054 ) — 13.11 20.94 — Expired (19,047 ) (9,143 ) (12,931 ) 56.88 48.18 33.48 Outstanding — end of year 2,492,179 2,813,280 2,263,977 11.35 14.14 18.66 Exercisable at end of year 1,701,445 1,811,320 1,336,694 $ 14.85 $ 17.70 $ 20.70 Weighted average fair value of stock options granted during the year: $ 1.47 $ 2.58 $ 11.28 For stock options paid in consideration of services rendered by non-employees, the Company recognizes compensation expense in accordance with the requirements of ASC 505-50. Non-employee option grants that do not vest immediately upon grant are recorded as an expense over the vesting period. At the end of each financial reporting period prior to performance, the value of these options, as calculated using the Black-Scholes option pricing model, is determined, and compensation expense recognized or recovered during the period is adjusted accordingly. Since the fair market value of options granted to non-employees is subject to change in the future, the amount of the future compensation expense is subject to adjustment until the common stock options are fully vested. The Company recorded approximately $422,000, $0 and $0 of non-cash charges related to the issuance of stock options to certain consultants in exchange for services during 2017, 2016 and 2015, respectively. At December 31, 2017, there was no unrecognized compensation expense related to unvested non-employee stock options. Presented below is the Company's non-employee stock option activity: Stock Options Weighted Average Exercise Price 2017 2016 2015 2017 2016 2015 Outstanding — beginning of year 100,000 105,952 115,357 $ 16.41 $ 18.12 $ 20.82 Granted 273,333 — — 1.78 — — Exercised — — — — — — Expired/Forfeited — (5,952 ) (9,405 ) — 46.62 51.24 Outstanding — end of year 373,333 100,000 105,952 5.70 16.41 18.12 Exercisable at end of year 373,333 100,000 105,952 $ 5.70 $ 16.41 $ 18.12 Weighted average fair value of stock options granted during the year: $ 1.54 $ — $ — The fair value of the stock options at the date of grant was estimated using the Black-Scholes option-pricing model, based on the following assumptions: 2017 2016 2015 Risk-free interest rate 2.30% - 2.35 % — — Expected volatility 92.00 % — — Expected lives (years) 10 — — Expected dividend yield — — — Range of Exercise Prices Number of Options Weighted Average RemainingContractual Life (years) Weighted Average Exercise Price Number of Options Exercisable Weighted Average Contractual Life Weighted Average Exercise Price $ 1.50 — 1.75 829,702 9.96 $ 1.75 400,000 9.96 $ 1.75 $ 1.76 —11.00 720,970 7.98 4.76 469,910 7.47 5.92 $ 11.01 — 15.00 776,290 7.20 13.92 667,290 7.07 13.80 $ 15.01 — 195.30 538,550 5.44 27.36 537,578 5.43 27.36 2,865,512 7.86 $ 10.62 2,074,778 7.29 $ 13.21 There was no aggregate intrinsic value to the outstanding options, options vested, and options exercised during 2017. The following table sets forth the total stock-based compensation expense resulting from stock options included in the Company's Statements of Operations: Years Ended December 31, 2017 2016 2015 Research and development - employee $ 549,315 $ 1,822,508 $ 1,590,267 General and administrative - employee 1,909,729 4,661,795 5,568,537 Total employee stock-based compensation $ 2,459,044 $ 6,484,303 $ 7,158,804 Research and development – non-employee $ 11,600 $ — $ — General and administrative – non-employee 410,400 235,764 225,852 Total non-employee stock-based compensation $ 422,000 $ 235,764 $ 225,852 Restricted Stock In December 2017, the Company granted to Steven Kriegsman, Chief Executive Officer, 387,597 shares of restricted common stock, pursuant to the 2008 Plan. This restricted stock vests in equal annual instalments over three years. The fair value of the restricted stock is based on the market price of the Company's shares on the grant date less the par value received as consideration. The fair value of the restricted stock on the grant date was $679,000. In December 2016, the Company granted to Steven Kriegsman, Chief Executive Officer, 387,597 shares of restricted common stock, pursuant to the 2008 Plan. This restricted stock vests in equal annual instalments over three years. The fair value of the restricted stock is based on the market price of the Company's shares on the grant date less the par value received as consideration. The fair value of the restricted stock on the grant date was $1,000,000. The Company did not issue any restricted stock for the year ended December 31, 2015. The Company recorded an employee stock-based compensation expense for restricted stock of approximately $344,000, $15,000 and $0 for the years ended December 31, 2017, 2016 and 2015, respectively. Equity-Classified Warrants In July 2017, pursuant to a Loan amendment (see Note 9), a portion of the warrants (representing 80% of the total number of shares issuable upon exercise of the warrants) was amended to change the exercise price of 84,554 warrants to $12.30 per share from $4.62 per share. In July 2017, the Company issued 500,000 warrants to purchase common stock as part of an exclusive licensing agreement granted to NantCell, Inc. In December 2016, the Company issued to a consultant an eighteen-month contingent warrant to purchase 333,334 shares of common stock at an exercise price of $4.20. No expense was recorded due to the performance contingent nature of the warrants. In February 2016, in connection with a loan and security agreement with Hercules Technology Growth Capital, Inc. and Hercules Technology III, L.P. ("lenders") (see Note 9), the Company issued to the lenders warrants to purchase a total of 105,691 shares of our common stock at an exercise price of $12.30. These warrants had a fair value of $633,749 on the date of issuance and were recorded as a loan discount. In February 2016, the Company also issued a warrant to a consultant to purchase 83,334 shares of our common stock at an exercise price of $10.44. These warrants will be fully vested by February 2018. The warrant expense in 2017 and 2016, recognized as non-employee stock-based compensation expenses, was $41,865 and $157,797, respectively. A summary of the Company's warrant activity and related information for the years ended December 31 are shown below. Warrants Weighted Average Exercise Price 2017 2016 2015 2017 2016 2015 Outstanding — beginning of year 5,417,155 1,204,245 1,224,960 $ 4.08 $ 25.68 $ 25.62 Granted 584,554 5,284,263 — 6.31 3.72 — Exercised (861,581 ) (9,393 ) (1,667 ) 3.66 4.20 15.00 Forfeited — — — — — — Expired (1,159,347 ) (1,061,960 ) (19,048 ) 4.92 26.88 22.92 Outstanding — end of year 3,980,781 5,417,155 1,204,245 4.26 4.08 25.68 Exercisable at end of year 3,626,613 5,031,715 1,204,245 $ 4.23 $ 4.02 $ 25.68 Weighted average fair value of warrants granted during the year: $ 1.65 $ 1.56 $ — The following table summarizes additional information concerning warrants outstanding and exercisable at December 31, 2017: Warrants Outstanding Range of Exercise Prices Number of Shares Weighted Average RemainingContractual Life (years) Weighted Average Exercise Price Number of Warrants Exercisable Weighted Average Contractual Life Weighted Average Exercise Price $ 3.00 — 6.00 3,252,137 0.60 $ 3.19 2,918,803 0.62 $ 3.08 $ 6.01 — 9.00 500,000 1.07 6.60 500,000 1.07 6.60 $ 9.01 — 12.00 83,335 3.11 10.44 62,501 3.11 10.44 $ 12.01 — 33.60 145,309 1.19 16.65 145,309 1.19 16.65 3,980,781 0.74 $ 4.26 3,626,613 0.75 $ 4.23

Stockholder Protection Rights P

Stockholder Protection Rights Plan	12 Months Ended
	Dec. 31, 2017
Stockholder Protection Rights Plan [Abstract]
Stockholder Protection Rights Plan	14. Stockholder Protection Rights Plan Effective April 16, 1997, the Company's board of directors declared a distribution of one right ("Rights") for each outstanding share of the Company's common stock to stockholders of record at the close of business on May 15, 1997 and for each share of common stock issued by the Company thereafter and prior to a Flip-in Date (as defined below). Each Right entitles the registered holder to purchase from the Company one-ten thousandth (1/10,000th) of a share of Series A Junior Participating Preferred Stock, at an exercise price of $30. The Rights are generally not exercisable until 10 business days after an announcement by the Company that a person or group of affiliated persons (an "Acquiring Person") has acquired beneficial ownership of 15% or more of the Company's then outstanding shares of common stock (a "Flip-in Date"). In the event the Rights become exercisable as a result of the acquisition of shares, each Right will enable the owner, other than the Acquiring Person, to purchase at the Right's then-current exercise price a number of shares of common stock with a market value equal to twice the exercise price. In addition, unless the Acquiring Person owns more than 50% of the outstanding shares of common stock, the Board of Directors may elect to exchange all outstanding Rights (other than those owned by such Acquiring Person) at an exchange ratio of one share of common stock per Right. All Rights that are owned by any person on or after the date such person becomes an Acquiring Person will be null and void. The Rights have been distributed to protect the Company's stockholders from coercive or abusive takeover tactics and to give the Board of Directors more negotiating leverage in dealing with prospective acquirers. In July 2016, the Company extended the stockholder rights plan through April 2022.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Taxes [Abstract]
Income Taxes	15. Income Taxes At December 31, 2017, the Company had federal and state net operating loss carryforwards of $373.7 million and $236.3 million, respectively, available to offset against future taxable income, which expire in 2018 through 2037. As a result of a change in-control that occurred in the CytRx shareholder base in 2013, approximately $136.8 million in federal net operating loss carryforwards became substantially limited in their annual availability. Management currently believes that the remaining $236.9 million in federal net operating loss carryforwards, and the $236.3 million in state net operating loss carryforwards, are unrestricted. As of December 31, 2017, CytRx also had research and development tax credits for federal and state purposes of approximately $16.6 million and $21.9 million, respectively, available for offset against future income taxes, which expire in 2022 through 2037. Based on an assessment of all available evidence including, but not limited to, the Company's limited operating history in its core business and lack of profitability, uncertainties of the commercial viability of its technology, the impact of government regulation and healthcare reform initiatives, and other risks normally associated with biotechnology companies, the Company has concluded that it is more likely than not that these net operating loss carryforwards and credits will not be realized and, as a result, a 100% deferred tax valuation allowance has been recorded against these assets. On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (the 2017 Tax Act) was enacted reducing the corporate tax rate from 35% to 21% which is effective on January 1, 2018. The carrying value of the Company's deferred tax assets is also determined by the enacted U.S. corporate income tax rate. Consequently, any changes in the U.S. corporate income tax rate have impacted the carrying value of the Company's deferred tax assets. Under the new corporate income tax rate of 21%, deferred income taxes decreased but there is a corresponding decrease to the valuation allowance. Therefore, the 2017 Tax Act is expected to have no impact on the Company's 2017 earnings. Staff Accounting Bulletin No. 118 ("SAB 118") was issued to address the application of US GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Act. In accordance with SAB 118, the Company has determined that the $27.3 million of deferred tax expense recorded in connection with the remeasurement of certain deferred tax assets and liabilities. The Company implemented ASU 2016-09 during the first quarter of 2017 as stipulated in the FASB guidance for publicly-traded entities. To account for the implementation of ASU 2016-09, the Company accounted for previously unrecognized excess tax benefits by recognizing those benefits. Due to the Company's full valuation allowance, this recognition has no effect on the net accrual after the valuation allowance. Deferred income taxes reflect the net effect of temporary differences between the financial reporting carrying amounts of assets and liabilities and income tax carrying amounts of assets and liabilities. The components of the Company's deferred tax assets and liabilities, all of which are long-term, are as follows (in thousands): December 31, 2017 2016 Deferred tax assets: Net operating loss carryforwards $ 66,251 $ 126,244 Tax credit carryforwards 33,899 29,970 Equipment, furnishings and other 4,909 9,297 Total deferred tax assets 105,059 165,511 Deferred tax liabilities — (301 ) Net deferred tax assets 105,059 165,210 Valuation allowance (105,059 ) (165,210 ) $ — $ — For all years presented, the Company did not recognize any deferred tax assets or liabilities. The net change in valuation allowance for the years ended December 31, 2017 and 2016 was $60.2 million and $21.4 million, respectively. The provision for income taxes differs from the provision computed by applying the Federal statutory rate to net loss before income taxes as follows (in thousands): Years ended December 31, 2017 2016 2015 Federal benefit at statutory rate $ (11,895 ) $ (17,262 ) $ (19,919 ) State income taxes, net of Federal taxes (2,073 ) (3,086 ) (3,556 ) State credits (506 ) (1,031 ) (1,324 ) Warrant liabilities (465 ) (1,301 ) (1,509 ) Other permanent differences 11 40 16 Provision related to change in valuation allowance (60,358 ) 21,601 20,142 Federal rate adjustment 27,314 — — NQ Options 47 — — Current year tax credit (665 ) (1,119 ) (2,050 ) NOL Adjustments 45,521 — — Termination/Cancellation of Equity Compensation Awards 2,983 2,274 5,960 Return to provision 84 (118 ) 2,238 Other, net 3 3 3 $ 1 $ 1 $ 1 There have been no changes to the Company's liability for unrecognized tax benefits during the year ended December 31, 2017. The Company files income tax returns in the U.S. Federal jurisdiction and various state jurisdictions. As of the year ended December 31, 2017, the tax returns for 2013 through 2017 remain open to examination by the Internal Revenue Service and various state tax authorities. The Company's policy is to recognize any interest and penalties related to unrecognized tax benefits as a component of income tax expense. As of the date of adoption of ASC 740 and the years ended December 31, 2017, 2016 and 2015, the Company had accrued no interest or penalties related to uncertain tax positions.

Quarterly Financial Data (unaud

Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Data (unaudited) [Abstract]
Quarterly Financial Data (unaudited)	16. Quarterly Financial Data (unaudited) Summarized quarterly financial data for 2017 and 2016 is as follows (in thousands, except per share data): Quarters Ended March 31 June 30 September 30 December 31 (In thousands, except per share data) 2017 Total revenues $ — $ — $ — $ 100 Net loss $ (11,044 ) $ (14,358 ) $ (5,124 ) $ (4,460 ) Basic and diluted loss per share applicable to common stock $ (0.60 ) $ (0.60 ) $ (1.14 ) $ (0.16 ) 2016 Total revenues $ — $ 100 $ — $ 100 Net loss $ (12,643 ) $ (18,280 ) $ (12,175 ) $ (7,672 ) Basic and diluted loss per share applicable to common stock $ (1.14 ) $ (1.62 ) $ (0.78 ) $ (0.48 ) Quarterly and year-to-date loss per share amounts are computed independently of each other. Therefore, the sum of the per share amounts for the quarters may not agree to the per share amounts for the year.

SCHEDULE II - VALUATION AND QUA

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 31, 2017
SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS [Abstract]
SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS	CYTRX CORPORATION SCHEDULE II — VALUATION AND QUALIFYING ACCOUNTS For the Years Ended December 31, 2017, 2016 and 2015 Additions Description Balance at Beginning of Year Charged to Costs and Expenses Charged to Other Accounts Deductions Balance at End of Year Reserve Deducted in the Balance Sheet from the Asset to Which it Applies: Allowance for Deferred Tax Assets Year ended December 31, 2017 $ 165,210,000 $ — $ (60,151,000 ) $ — $ 105,059,000 Year ended December 31, 2016 $ 143,609,000 $ — $ 21,601,000 $ — $ 165,210,000 Year ended December 31, 2015 $ 123,466,000 $ — $ 20,143,000 $ — $ 143,609,000

Summary of Significant Accoun24

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Summary of Significant Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation
Revenue Recognition	Revenue Recognition Since 2011, the Company has followed the Financial Accounting Standards Board ("FASB") Accounting Standards Codifications ("ASC") ASC 605-25, Revenue Recognition – Multiple-Element Arrangements
Other Income (Expense)	Other Income (Expense)
Cash Equivalents	Cash Equivalents
Equipment and Furnishings	Equipment and Furnishings
Fair Value Measurements	Fair Value Measurements Level 1 – quoted prices in active markets for identical assets or liabilities. Level 2 – other significant observable inputs for the assets or liabilities through corroboration with market data at the measurement date. Level 3 – significant unobservable inputs that reflect management's best estimate of what market participants would use to price the assets or liabilities at the measurement date. The following table summarizes fair value measurements by level at December 31, 2017 for assets and liabilities measured at fair value on a recurring basis: (In thousands) Level I Level II Level III Total Cash equivalents $ 35,834 $ — $ — $ 35,834 Warrant liabilities — — (527 ) (527 ) The following table summarizes fair value measurements by level at December 31, 2016 for assets and liabilities measured at fair value on a recurring basis: (In thousands) Level I Level II Level III Total Cash equivalents $ 56,276 $ — $ — $ 56,276 Warrant liabilities — — (3,789 ) (3,789 ) There were no transfers between Levels I, II and III during 2017 or 2016. The changes in carrying amounts of the warrant liability for the years ended December 31, 2017 and 2016 were as follows: (In thousands) 2017 2016 Beginning balance $ 3,789 $ 693 Issued — 6,933 Exercised (1,895 ) (9 ) Net changes in valuation (1,367 ) (3,828 ) Ending balance $ 527 $ 3,789 Liabilities measured at fair market value on a recurring basis include warrant liabilities resulting from recent debt and equity financing. In accordance with ASC 815-40, Derivatives and Hedging – Contracts in Entity's Own Equity the warrant liabilities are being marked to fair value each quarter-end until they are completely settled. The warrants are valued using the Black-Scholes method, using assumptions consistent with the Company's application of ASC 505-50, Equity-Based Payments to Non-Employees ("ASC 505-50"). See Warrant Liabilities below. The Company considers carrying amounts of accounts receivable, accounts payable, accrued expenses and term loan, net to approximate fair value due to the short-term nature of these financial instruments.
Patents and Patent Application Costs	Patents and Patent Application Costs
Net Income (Loss) Per Common Share	Net Income (Loss) Per Common Share
Warrant Liabilities	Warrant Liabilities
Stock-based Compensation	Stock-based Compensation For stock options and stock warrants paid in consideration of services rendered by non-employees, the Company recognizes compensation expense in accordance with the requirements of ASC 505-50 , Equity ,
Research and Development Expenses	Research and Development Expenses
Clinical Trial Expenses	Clinical Trial Expenses
Income Taxes	Income Taxes Income Taxes, ("ASC 740" On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (the 2017 Tax Act) was enacted reducing the corporate tax rate from 35% to 21% which is effective on January 1, 2018. The carrying value of the Company's deferred tax assets is also determined by the enacted U.S. corporate income tax rate. Consequently, any changes in the U.S. corporate income tax rate have impacted the carrying value of the Company's deferred tax assets. Under the new corporate income tax rate of 21%, deferred income taxes decreased but there is a corresponding decrease to the valuation allowance. Therefore, the 2017 Tax Act is expected to have no impact on the Company's 2017 earnings. In accordance with Staff Accounting Bulletin No. 118, as of December 31, 2017, the Company has not completed its accounting for the tax effects of the enactment of the 2017 Tax Act; however, the Company has made a reasonable estimate of the effects on its existing deferred tax balances. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained upon examination by the taxing authorities based on the technical merits of the position. The Company's policy is to recognize any interest and penalties related to unrecognized tax benefits as a component of income tax expenses.
Concentrations of Risks	Concentrations of Risks
Use of Estimates	Use of Estimates
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2016, the Financial Accounting Standards Board issued ASU No. 2016-15 "Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the Emerging Issues Task Force)." The objective of ASU No. 2016-15 is to provide specific guidance on eight cash flow classification issues and how to reduce diversity in how certain cash receipts and cash payments are presented and classified in the statement of cash flows under Topic 230, Statement of Cash Flows, and other Topics. The amendments in this update are effective for public business entities for fiscal years beginning after December 15, 2017 and interim periods within those fiscal years. The Company is still in the process of determining the impact that the implementation of ASU 2016-15 will have on its financial statements. In March 2016, the FASB issued Accounting Standards Update 2016-09, Compensation—Stock Compensation In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)," which requires companies to recognize all leases as assets and liabilities on the consolidated balance sheet. This ASU retains a distinction between finance leases and operating leases, and the classification criteria for distinguishing between finance leases and operating leases are substantially similar to the classification criteria for distinguishing between capital leases and operating leases in the current accounting literature. The result of retaining a distinction between finance leases and operating leases is that under the lessee accounting model in Topic 842, the effect of leases in a statement of operations and a statement of cash flows is largely unchanged from previous GAAP. The amendments in this ASU are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Earlier adoption is permitted. Although the Company has not finalized its process of evaluating the impact of adoption of the ASU on its financial statements, the Company expects there will not be a material increase to assets and liabilities on the Company's balance sheet for leases currently classified as operating leases. In January 2016, the FASB issued ASU No. 2016-01 " Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. In November 2015, the FASB issued ASU No. 2015-17 "Income Taxes: Balance Sheet Classification of Deferred Taxes." In May 2014, the FASB issued Accounting Standards Update No. 2014-09 (Topic 606) " Revenue from Contracts with Customers Revenue Recognition currently assessing the method of adoption and the impact this new guidance will have on its financial statements. The Company expects to adopt these standards using the modified retrospective method. The timing of revenue recognition for variable consideration under our licensing and collaboration agreements may be different as a result of this new guidance. The Company is reviewing its licensing agreement for variable consideration, and if any such consideration exists, whether it should be estimated and recognized earlier than under the current revenue guidance. In August 2015, the FASB issued ASU No. 2015-14, "Revenue from Contracts with Customers" ("ASU 2015-14") which deferred the effective date by one year to December 15, 2017 for interim and annual reporting periods beginning after that date and allows for adoption using a full retrospective method, or a modified retrospective method. The Company will adopt the new standard in its first quarter 2018 using the modified retrospective method and is currently in the process of evaluating the impact of the adoption of this standard on its financial statements.

Summary of Significant Accoun25

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Summary of Significant Accounting Policies [Abstract]
Fair Value Measurements by Level for Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table summarizes fair value measurements by level at December 31, 2017 for assets and liabilities measured at fair value on a recurring basis: (In thousands) Level I Level II Level III Total Cash equivalents $ 35,834 $ — $ — $ 35,834 Warrant liabilities — — (527 ) (527 ) The following table summarizes fair value measurements by level at December 31, 2016 for assets and liabilities measured at fair value on a recurring basis: (In thousands) Level I Level II Level III Total Cash equivalents $ 56,276 $ — $ — $ 56,276 Warrant liabilities — — (3,789 ) (3,789 )
Changes in Carrying Amounts of Warrant Liabilities	The changes in carrying amounts of the warrant liability for the years ended December 31, 2017 and 2016 were as follows: (In thousands) 2017 2016 Beginning balance $ 3,789 $ 693 Issued — 6,933 Exercised (1,895 ) (9 ) Net changes in valuation (1,367 ) (3,828 ) Ending balance $ 527 $ 3,789

Equipment and Furnishings (Tabl

Equipment and Furnishings (Tables)	12 Months Ended
	Dec. 31, 2017
Equipment and Furnishings [Abstract]
Equipment and Furnishings	Equipment and furnishings at December 31, 2017 and 2016 consist of the following (in thousands): 2017 2016 Equipment and furnishings $ 2,212 $ 2,811 Less — accumulated depreciation (1,169 ) (851 ) Equipment and furnishings, net $ 1,043 $ 1,960

Accrued Expenses and Other Cu27

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Accrued Expenses and Other Current Liabilities [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities at December 31, 2017 and 2016 are summarized below (in thousands) 2017 2016 Professional fees $ 209 $ 193 Research and development costs 223 2,208 Litigation settlement 6,450 700 Wages, bonuses and employee benefits 396 487 Royalties 626 — Other 125 242 Total $ 8,029 $ 3,830

Term Loan (Tables)

Term Loan (Tables)	12 Months Ended
	Dec. 31, 2017
Term Loan [Abstract]
Schedule of Term Loan	As security for the Company's obligations under the loan and securities agreement, the Company granted HTGC, as administrative agent, a security interest in substantially all of its existing and after-acquired assets except for its intellectual property and certain other excluded assets. December 31, 2017 December 31, 2016 Term Loan Principal – Current $ 9,986,362 $ 6,214,057 End Fee Payable 1,771,250 — Issuance Cost/Loan Discount – Current (1,157,817 ) (732,401 ) Term Loan, Net – Current $ 10,599,795 $ 5,481,656 Long Term Loan Principal $ — $ 18,785,943 End Fee Payable — 1,771,250 Long Term Loan Discount/Issuance Cost — (2,072,683 ) Long Term Loan, Net $ — $ 18,484,510

Warrant Liabilities (Tables)

Warrant Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Warrant Liabilities [Abstract]
Schedule of Weighted-Average Assumptions	The following reflects the weighted-average assumptions for each of the periods indicated: Year Ended December 31, 2017 2016 2015 Risk-free interest rate 1.53 % 0.90 % 0.57 % Expected dividend yield 0 % 0 % 0 % Expected lives 0.55 1.23 0.59 Expected volatility 96.7 % 119.1 % 61.7 % Number of warrants classified as liabilities 2,834,246 4,752,512 1,061,976 Gain on warrant liabilities $ 1,367,777 $ 3,827,617 $ 4,437,628

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies [Abstract]
Current Contractual Obligations	CytRx's current contractual obligations that will require future cash payments are as follows (in thousands): Operating Leases (1) Employment Agreements (2) Research and Development (3) Total 2018 $ 373 $ 1,678 $ 1,000 $ 3,051 2019 278 1,057 — 1,335 2020 59 1,057 — 1,116 2021 — 1,057 — 1,057 2022 — — — — Thereafter — — — — Total $ 710 $ 4,849 $ 1,000 $ 6,559 ____________ (1) Operating leases are primarily facility lease related obligations, as well as equipment lease obligations with third party vendors. The Company recognized rent expenses of $420,106, $358,247, and $351,075 in 2017, 2016 and 2015, respectively. (2) Employment agreements include management contracts which have been revised from time to time. The employment agreement for the Company's executive officers provide for minimum salaries, which are adjusted annually at the discretion of the Company's Compensation Committee, and in some cases provide for minimum annual bonuses and employee benefits, as well. New employment agreements for the Company's other executive officers are usually entered into annually or biennially. (3) Research and development obligations relate primarily to the Reimbursement Agreement with NantCell. All of these purchase obligations are cancelable.

Stock Options and Equity-Clas31

Stock Options and Equity-Classified Warrants (Tables)	12 Months Ended
	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Total Stock-Based Compensation Expense from Stock Options	The following table sets forth the total stock-based compensation expense resulting from stock options included in the Company's Statements of Operations: Years Ended December 31, 2017 2016 2015 Research and development - employee $ 549,315 $ 1,822,508 $ 1,590,267 General and administrative - employee 1,909,729 4,661,795 5,568,537 Total employee stock-based compensation $ 2,459,044 $ 6,484,303 $ 7,158,804 Research and development – non-employee $ 11,600 $ — $ — General and administrative – non-employee 410,400 235,764 225,852 Total non-employee stock-based compensation $ 422,000 $ 235,764 $ 225,852
Significant Ranges of Outstanding Stock Options and Warrants	The following table summarizes significant ranges of outstanding stock options under the two plans at December 31, 2017: Range of Exercise Prices Number of Options Weighted Average RemainingContractual Life (years) Weighted Average Exercise Price Number of Options Exercisable Weighted Average Contractual Life Weighted Average Exercise Price $ 1.50 — 1.75 829,702 9.96 $ 1.75 400,000 9.96 $ 1.75 $ 1.76 —11.00 720,970 7.98 4.76 469,910 7.47 5.92 $ 11.01 — 15.00 776,290 7.20 13.92 667,290 7.07 13.80 $ 15.01 — 195.30 538,550 5.44 27.36 537,578 5.43 27.36 2,865,512 7.86 $ 10.62 2,074,778 7.29 $ 13.21
Stock Options [Member] | Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair Value Assumptions of Stock Options	The fair value of the stock options at the date of grant was estimated using the Black-Scholes option-pricing model, based on the following assumptions: 2017 2016 2015 Risk-free interest rate 2.04% - 2.35 % 1.20% - 2.26 % 1.74% - 2.12 % Expected volatility 86% - 92 % 74% - 88 % 74% - 85 % Expected lives (years) 6 - 10 6 - 10 6 - 10 Expected dividend yield 0.00 % 0.00 % 0.00 %
Stock Options [Member] | Non-employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair Value Assumptions of Stock Options	The fair value of the stock options at the date of grant was estimated using the Black-Scholes option-pricing model, based on the following assumptions: 2017 2016 2015 Risk-free interest rate 2.30% - 2.35 % — — Expected volatility 92.00 % — — Expected lives (years) 10 — — Expected dividend yield — — —
Stock Options and Warrants Activity	Presented below is the Company's non-employee stock option activity: Stock Options Weighted Average Exercise Price 2017 2016 2015 2017 2016 2015 Outstanding — beginning of year 100,000 105,952 115,357 $ 16.41 $ 18.12 $ 20.82 Granted 273,333 — — 1.78 — — Exercised — — — — — — Expired/Forfeited — (5,952 ) (9,405 ) — 46.62 51.24 Outstanding — end of year 373,333 100,000 105,952 5.70 16.41 18.12 Exercisable at end of year 373,333 100,000 105,952 $ 5.70 $ 16.41 $ 18.12 Weighted average fair value of stock options granted during the year: $ 1.54 $ — $ —
Stock Options [Member] | Employees and Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Options and Warrants Activity	Presented below is the Company's stock option activity for employees and directors: Stock Options Weighted Average Exercise Price 2017 2016 2015 2017 2016 2015 Outstanding — beginning of year 2,813,280 2,263,977 1,559,765 $ 14.14 $ 18.66 $ 16.98 Granted 591,369 809,500 765,000 1.87 3.54 15.66 Exercised (19,213 ) (55,000 ) (47,857 ) 2.58 12.84 12.30 Forfeited (874,210 ) (196,054 ) — 13.11 20.94 — Expired (19,047 ) (9,143 ) (12,931 ) 56.88 48.18 33.48 Outstanding — end of year 2,492,179 2,813,280 2,263,977 11.35 14.14 18.66 Exercisable at end of year 1,701,445 1,811,320 1,336,694 $ 14.85 $ 17.70 $ 20.70 Weighted average fair value of stock options granted during the year: $ 1.47 $ 2.58 $ 11.28
Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Options and Warrants Activity	A summary of the Company's warrant activity and related information for the years ended December 31 are shown below. Warrants Weighted Average Exercise Price 2017 2016 2015 2017 2016 2015 Outstanding — beginning of year 5,417,155 1,204,245 1,224,960 $ 4.08 $ 25.68 $ 25.62 Granted 584,554 5,284,263 — 6.31 3.72 — Exercised (861,581 ) (9,393 ) (1,667 ) 3.66 4.20 15.00 Forfeited — — — — — — Expired (1,159,347 ) (1,061,960 ) (19,048 ) 4.92 26.88 22.92 Outstanding — end of year 3,980,781 5,417,155 1,204,245 4.26 4.08 25.68 Exercisable at end of year 3,626,613 5,031,715 1,204,245 $ 4.23 $ 4.02 $ 25.68 Weighted average fair value of warrants granted during the year: $ 1.65 $ 1.56 $ —
Significant Ranges of Outstanding Stock Options and Warrants	The following table summarizes additional information concerning warrants outstanding and exercisable at December 31, 2017: Warrants Outstanding Range of Exercise Prices Number of Shares Weighted Average RemainingContractual Life (years) Weighted Average Exercise Price Number of Warrants Exercisable Weighted Average Contractual Life Weighted Average Exercise Price $ 3.00 — 6.00 3,252,137 0.60 $ 3.19 2,918,803 0.62 $ 3.08 $ 6.01 — 9.00 500,000 1.07 6.60 500,000 1.07 6.60 $ 9.01 — 12.00 83,335 3.11 10.44 62,501 3.11 10.44 $ 12.01 — 33.60 145,309 1.19 16.65 145,309 1.19 16.65 3,980,781 0.74 $ 4.26 3,626,613 0.75 $ 4.23

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Taxes [Abstract]
Deferred Tax Assets and Liabilities	The components of the Company's deferred tax assets and liabilities, all of which are long-term, are as follows (in thousands): December 31, 2017 2016 Deferred tax assets: Net operating loss carryforwards $ 66,251 $ 126,244 Tax credit carryforwards 33,899 29,970 Equipment, furnishings and other 4,909 9,297 Total deferred tax assets 105,059 165,511 Deferred tax liabilities — (301 ) Net deferred tax assets 105,059 165,210 Valuation allowance (105,059 ) (165,210 ) $ — $ —
Effective Income Tax Rate Reconciliation	The provision for income taxes differs from the provision computed by applying the Federal statutory rate to net loss before income taxes as follows (in thousands): Years ended December 31, 2017 2016 2015 Federal benefit at statutory rate $ (11,895 ) $ (17,262 ) $ (19,919 ) State income taxes, net of Federal taxes (2,073 ) (3,086 ) (3,556 ) State credits (506 ) (1,031 ) (1,324 ) Warrant liabilities (465 ) (1,301 ) (1,509 ) Other permanent differences 11 40 16 Provision related to change in valuation allowance (60,358 ) 21,601 20,142 Federal rate adjustment 27,314 — — NQ Options 47 — — Current year tax credit (665 ) (1,119 ) (2,050 ) NOL Adjustments 45,521 — — Termination/Cancellation of Equity Compensation Awards 2,983 2,274 5,960 Return to provision 84 (118 ) 2,238 Other, net 3 3 3 $ 1 $ 1 $ 1

Quarterly Financial Data (una33

Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Data (unaudited) [Abstract]
Quarterly Financial Information	Summarized quarterly financial data for 2017 and 2016 is as follows (in thousands, except per share data): Quarters Ended March 31 June 30 September 30 December 31 (In thousands, except per share data) 2017 Total revenues $ — $ — $ — $ 100 Net loss $ (11,044 ) $ (14,358 ) $ (5,124 ) $ (4,460 ) Basic and diluted loss per share applicable to common stock $ (0.60 ) $ (0.60 ) $ (1.14 ) $ (0.16 ) 2016 Total revenues $ — $ 100 $ — $ 100 Net loss $ (12,643 ) $ (18,280 ) $ (12,175 ) $ (7,672 ) Basic and diluted loss per share applicable to common stock $ (1.14 ) $ (1.62 ) $ (0.78 ) $ (0.48 )

Nature of Business (Details)

Nature of Business (Details)	Jul. 27, 2017USD ($)$ / sharesshares	Dec. 31, 2017USD ($)ClassDrugCandidatePatient$ / shares	Dec. 31, 2016USD ($)	Dec. 16, 2016$ / shares	Dec. 15, 2016$ / shares	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Nature of Business [Abstract]
Number of classes of ultra-high potency drug conjugates | Class		2
Number of designed drug conjugates with highly potent cytotoxic payloads | Drug		75
Number of distinct classes of compound | Class		2
Number of lead candidates | Candidate		4
Number of patients tested for various types of cancer | Patient		600
Number of years Orphan Drug Designation provides several benefits of market exclusivity after approval		7 years
Number of years soft tissue sarcomas confers market among other benefits		10 years
Schedule of Strategic Investment Agreement [Line Items]
Warrants exercise price (in dollars per share) | $ / shares		$ 30		$ 3.06	$ 4.20
Estimated Projected Expenditure Type [Line Items]
Cash and cash equivalents		$ 37,643,404	$ 56,959,485			$ 22,261,372	$ 32,218,905
Period for projected cash burn required to be maintained		3 months
Projected cash burn		$ 10,000,000
Projected expenditures for clinical programs		$ 27,800,000
Reserve stock split		6
Clinical Programs [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		$ 1,500,000
Albumin-Binding Cancer Drugs [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		3,100,000
General Operation [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		700,000
Other General and Administrative Expenses [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		10,100,000
Interest and Principal Payments [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		$ 12,400,000
NantCell, Inc [Member]
Schedule of Strategic Investment Agreement [Line Items]
Net proceeds received from the sale of common stock	$ 13,000,000
Common stock, share price (in dollars per share) | $ / shares	$ 6.60
Percentage of common stock premium at market price	92.00%
Warrants to purchase shares of common stock (in shares) | shares	500,000
Warrants exercise price (in dollars per share) | $ / shares	$ 6.60
Period to purchase common stock by exercising warrants	18 months
NantCell, Inc [Member] | Maximum [Member]
Schedule of Strategic Investment Agreement [Line Items]
Fee contingent payments entitled to be received under license agreement	$ 343,000,000

Summary of Significant Accoun35

Summary of Significant Accounting Policies (Details) - USD ($) shares in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of Significant Accounting Policies [Abstract]
Foreign exchange gain			$ 200,000
Changes in carrying amounts of warrant liabilities [Abstract]
Beginning balance	$ 527,025	$ 3,789,391	693,000
Issued		0	6,933,000
Exercised		(1,895,000)	(9,000)
Net changes in valuation		(1,367,000)	(3,828,000)
Ending balance		$ 527,025	$ 3,789,391	$ 693,000
Antidilutive securities excluded from computation of earning per share amount (in shares)		7.6	8.3	3.6
Income Tax Disclosure [Line Items]
Federal corporate tax rate		35.00%
Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents		$ 35,834,000	$ 56,276,000
Warrant liabilities		$ (527,000)	(3,789,000)
Plan [Member]
Income Tax Disclosure [Line Items]
Federal corporate tax rate	21.00%
Minimum [Member]
Property, Plant and Equipment [Line Items]
Useful life		3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Useful life		5 years
Level I [Member] | Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents		$ 35,834,000	56,276,000
Warrant liabilities		0	0
Level II [Member] | Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents		0	0
Warrant liabilities		0	0
Level III [Member] | Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents		0	0
Warrant liabilities		$ (527,000)	$ (3,789,000)

Foreign Currency Remeasurement

Foreign Currency Remeasurement (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Foreign Currency Remeasurement [Abstract]
Loss on foreign currency translation adjustment	$ (23,000)	$ (18,000)	$ (6,000)

Receivables (Details)

Receivables (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Receivables [Abstract]
Receivables	$ 7,529,032	$ 183,703
Recoverable legal costs	1,700,000	200,000
Recoverable legal settlements	$ 5,800,000	$ 0

Prepaid and Other Assets (Detai

Prepaid and Other Assets (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Prepaid and Other Assets [Abstract]
Prepaid and other assets	$ 1,914,077	$ 3,434,238

Equipment and Furnishings (Deta

Equipment and Furnishings (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Equipment and Furnishings [Abstract]
Equipment and furnishings	$ 2,212,000	$ 2,811,000
Less - accumulated depreciation	(1,169,000)	(851,000)
Equipment and furnishings, net	1,042,892	1,959,667
Depreciation and amortization	$ 629,312	$ 536,631	$ 317,649

Accrued Expenses and Other Cu40

Accrued Expenses and Other Current Liabilities (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Accounts Payable and Accrued Liabilities, Current [Abstract]
Professional fees	$ 209,000	$ 193,000
Research and development costs	223,000	2,208,000
Litigation settlement	6,450,000	700,000
Wages, bonuses and employee benefits	396,000	487,000
Royalties	626,000	0
Other	125,000	242,000
Total	$ 8,029,274	$ 3,830,498

Deferred Revenues (Details)

Deferred Revenues (Details) - USD ($)	Dec. 31, 2017	Oct. 03, 2017	Dec. 31, 2016
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 6,924,353		$ 0
NantCell, Inc [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 6,900,000
NantCell, Inc [Member] | Maximum [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue		$ 4,200,000

Term Loan (Details)

Term Loan (Details) - USD ($)	Jul. 31, 2017	Jul. 28, 2017	Feb. 08, 2016	Feb. 05, 2016	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 16, 2016	Dec. 15, 2016	Feb. 29, 2016
Debt Instrument [Line Items]
Amount received under initial loan agreement						$ 0	$ 24,012,078	$ 0
Warrants exercise price (in dollars per share)						$ 30			$ 3.06	$ 4.20
Debt instrument, repayment of principal and unpaid interest						$ 15,013,638	0	0
Warrants repriced in connection with debt modification						76,549	0	$ 0
Term Loan, Net - Current						10,599,795	5,481,656
Long Term Loan, Net						$ 0	18,484,510
Warrants [Member]
Debt Instrument [Line Items]
Number of warrants issued (in shares)											83,334
Warrants exercise price (in dollars per share)											$ 10.44
Hercules Capital, Inc. and Hercules Technology III, L.P. [Member]
Debt Instrument [Line Items]
Amount received under initial loan agreement			$ 25,000,000
Debt instrument, interest rate				10.50%
Debt instrument, maturity date						Feb. 1, 2020
Debt instrument, minimum cash balance required to be maintained				$ 10,000,000
Debt instrument, repayment of principal and unpaid interest		$ 5,000,000			$ 5,000,000
Prepayment charge		$ 100,000
Second prepayment charge						$ 100,000
Maturity date of amended loan servicing agreement						Aug. 1, 2018
Percentage of stock issuable upon exercise of the warrants	80.00%	80.00%
Number of days to calculate volume-weighted average price of common stock						30 days
Warrants repriced in connection with debt modification						$ 77,000
Additional loan discount						200,000
Term Loan Principal - Current						9,986,362	6,214,057
End Fee Payable						1,771,250	0
Issuance Cost/Loan Discount - Current						(1,157,817)	(732,401)
Term Loan, Net - Current						10,599,795	5,481,656
Long Term Loan Principal						0	18,785,943
End Fee Payable						0	1,771,250
Long Term Loan Discount/Issuance Cost						0	(2,072,683)
Long Term Loan, Net						0	18,484,510
Hercules Capital, Inc. and Hercules Technology III, L.P. [Member] | Warrants [Member]
Debt Instrument [Line Items]
Number of warrants issued (in shares)				105,691
Warrants exercise price (in dollars per share)	$ 4.62	$ 4.62		$ 12.30
Fair value of warrants classified as equity warrants						$ 633,749	$ 633,749
Hercules Capital, Inc. and Hercules Technology III, L.P. [Member] | Prime Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				6.00%

Warrant Liabilities (Details)

Warrant Liabilities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Gain on warrant liabilities	$ 1,367,777	$ 3,827,617	$ 4,437,628
Warrants issued (in shares)	1,200,000	4,800,000
Exercised (in shares)	900,000
Warrant [Member]
Derivative [Line Items]
Risk-free interest rate	1.53%	0.90%	0.57%
Expected dividend yield	0.00%	0.00%	0.00%
Expected lives	6 months 18 days	1 year 2 months 23 days	7 months 2 days
Expected volatility	96.70%	119.10%	61.70%
Warrants classified as liabilities (in shares)	2,834,246	4,752,512	1,061,976
Gain on warrant liabilities	$ 1,367,777	$ 3,827,617	$ 4,437,628
Exercised (in shares)	900,000

Commitments and Contingencies44

Commitments and Contingencies (Details)		12 Months Ended
		Dec. 31, 2017USD ($)Complaint	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Operating Leases [Abstract]
2,018	[1]	$ 373,000
2,019	[1]	278,000
2,020	[1]	59,000
2,021	[1]	0
2,022	[1]	0
Thereafter	[1]	0
Total	[1]	710,000
Employment Agreements [Abstract]
2,018	[2]	1,678,000
2,019	[2]	1,057,000
2,020	[2]	1,057,000
2,021	[2]	1,057,000
2,022	[2]	0
Thereafter	[2]	0
Total	[2]	4,849,000
Research and Development [Abstract]
2,018	[3]	1,000,000
2,019	[3]	0
2,020	[3]	0
2,021	[3]	0
2,022	[3]	0
Thereafter	[3]	0
Total	[3]	1,000,000
Total [Abstract]
2,018		3,051,000
2,019		1,335,000
2,020		1,116,000
2,021		1,057,000
2,022		0
Thereafter		0
Total		6,559,000
Lease expense		420,106	$ 358,247	$ 351,075
Loss Contingencies [Line Items]
Potential future payments		7,500,000
Issuance of common stock		$ 28,037	$ 18,553
Number of competing derivative complaints | Complaint		2
Litigation setttlements		$ 6,500,000
Aldoxorubicin [Member]
Loss Contingencies [Line Items]
Issuance of common stock		$ 18,300,000
[1]	Operating leases are primarily facility lease related obligations, as well as equipment lease obligations with third party vendors. The Company recognized rent expenses of $420,106, $358,247, and $351,075 in 2017, 2016 and 2015, respectively.
[2]	Employment agreements include management contracts which have been revised from time to time. The employment agreement for the Company's executive officers provide for minimum salaries, which are adjusted annually at the discretion of the Company's Compensation Committee, and in some cases provide for minimum annual bonuses and employee benefits, as well. New employment agreements for the Company's other executive officers are usually entered into annually or biennially.
[3]	Research and development obligations relate primarily to the Reimbursement Agreement with NantCell. All of these purchase obligations are cancelable.

Equity Transactions (Details)

Equity Transactions (Details)	Jul. 27, 2017$ / sharesshares	May 02, 2017shares	Jul. 20, 2016shares	Oct. 26, 2015USD ($)shares	Jul. 24, 2015shares	Mar. 31, 2017shares	Sep. 30, 2017shares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)shares	Dec. 16, 2016USD ($)$ / sharesshares	Dec. 15, 2016$ / shares	Feb. 29, 2016$ / shares
Class of Stock [Line Items]
Authorized but unissued shares of common stock (in shares)								1,200,000
Number of treasury stock retired (in shares)				33,213	1,744,167
Stock issued as result of reverse stock split (in shares)								12,268
Reverse stock split								6
Common stock shares issued from exercise of warrants and options (in shares)							880,788
Issuance of common stock (in shares)	1,969,697	5,000,000
Number of treasury stock retired, value | $				$ 2,600,000						$ 0
Common stock shares issued (in shares)								28,037,501	18,553,817		1,923,457
Preferred stock, shares issued (in shares)								0	0
Number of warrants repriced (in shares)											3,232,981
Warrants exercise price (in dollars per share) | $ / shares								$ 30			$ 3.06	$ 4.20
Beneficial conversion feature - Series B preferred stock | $									$ 0
Common stock issued for litigation settlement (in shares)			4,761,905
Warrants exercised period			1 year
Series B Convertible Preferred Shares [Member]
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)								550	550
Preferred stock, stated value | $								$ 1,000	$ 1,000
Number of preferred shares converted (in shares)						(518)
Preferred stock, conversion value (in dollars per share) | $ / shares								$ 2.52	$ 2.52
NantCell, Inc [Member]
Class of Stock [Line Items]
Warrants exercise price (in dollars per share) | $ / shares	$ 6.60
Preferred Stock [Member] | Series B Convertible Preferred Shares [Member]
Class of Stock [Line Items]
Number of treasury stock retired (in shares)										0
Stock issued as result of reverse stock split (in shares)								0
Issuance of common stock (in shares)								0	550	0
Number of treasury stock retired, value | $										$ 0
Preferred stock, shares issued (in shares)											550
Preferred stock, stated value | $											$ 1,000
Number of preferred shares converted (in shares)								(518)	(32)
Preferred stock, conversion value (in dollars per share) | $ / shares									$ 2.52
Beneficial conversion feature - Series B preferred stock | $									$ 314,286
Common Stock [Member]
Class of Stock [Line Items]
Number of treasury stock retired (in shares)										33,213
Stock issued as result of reverse stock split (in shares)								12,268
Issuance of common stock (in shares)								5,000,000	6,685,362	1,744,167
Number of treasury stock retired, value | $										$ 33
Number of preferred shares converted (in shares)								1,233,334	76,191
Beneficial conversion feature - Series B preferred stock | $									$ 0
Common Stock [Member] | Series B Convertible Preferred Shares [Member]
Class of Stock [Line Items]
Number of preferred shares converted (in shares)						1,233,334
Employee Stock Option [Member]
Class of Stock [Line Items]
Stock issued during period (in shares)									55,000
Restricted Stock [Member]
Class of Stock [Line Items]
Stock issued during period (in shares)								387,597	387,597
Warrants [Member]
Class of Stock [Line Items]
Warrants exercise price (in dollars per share) | $ / shares													$ 10.44
Warrants [Member] | NantCell, Inc [Member]
Class of Stock [Line Items]
Issuance of common stock (in shares)	500,000

Stock Options and Equity-Clas46

Stock Options and Equity-Classified Warrants (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Vesting period	3 years
Average vesting period	6 years
Number of Options (Employees and Non-Employees) [Abstract]
Exercised (in shares)	(900,000)
Employees [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Estimated annualized forfeiture rate		10.00%	10.00%
Employees [Member] | Maximum [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Expected lives	10 years
Non-employees [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Unrecognized compensation expense related to unvested stock options, granted	$ 0
Weighted-Average Exercise Price Options [Abstract]
Issuance of stock options to certain consultants in exchange for services	422,000	$ 0	$ 0
Senior Management [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Estimated annualized forfeiture rate		2.00%	2.00%
Employees and Directors [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Unrecognized compensation expense related to unvested stock options, granted	$ 1,800,000
Unrecognized compensation cost, recognized as expense over a weighted-average period	1 year 1 month 24 days
Directors [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Estimated annualized forfeiture rate		0.00%	0.00%
Stock Options [Member] | Employees [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Expected dividend yield	0.00%	0.00%	0.00%
Stock Options [Member] | Employees [Member] | Minimum [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Risk-free interest rate	2.04%	1.20%	1.74%
Expected volatility	86.00%	74.00%	74.00%
Expected lives	6 years	6 years	6 years
Stock Options [Member] | Employees [Member] | Maximum [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Risk-free interest rate	2.35%	2.26%	2.12%
Expected volatility	92.00%	88.00%	85.00%
Expected lives	10 years	10 years	10 years
Stock Options [Member] | Non-employees [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Risk-free interest rate		0.00%	0.00%
Expected volatility	92.00%	0.00%	0.00%
Expected lives	10 years	0 years	0 years
Expected dividend yield	0.00%	0.00%	0.00%
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding - beginning of year (in shares)	100,000	105,952	115,357
Granted (in shares)	273,333	0	0
Exercised (in shares)	0	0	0
Expired/Forfeited (in shares)	0	(5,952)	(9,405)
Outstanding - end of year (in shares)	373,333	100,000	105,952
Exercisable at end of year (in shares)	373,333	100,000	105,952
Weighted average fair value of stock options granted during the year (in dollars per share)	$ 1.54	$ 0	$ 0
Weighted-Average Exercise Price Options [Abstract]
Outstanding - beginning of year (in dollars per share)	16.41	18.12	20.82
Granted (in dollars per share)	1.78	0	0
Exercised (in dollars per share)	0	0	0
Expired/Forfeited (in dollars per share)	0	46.62	51.24
Outstanding - end of year (in dollars per share)	5.70	16.41	18.12
Exercisable at end of year (in dollars per share)	$ 5.70	$ 16.41	$ 18.12
Stock Options [Member] | Non-employees [Member] | Minimum [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Risk-free interest rate	2.30%
Stock Options [Member] | Non-employees [Member] | Maximum [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Risk-free interest rate	2.35%
Stock Options [Member] | Employees and Directors [Member]
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding - beginning of year (in shares)	2,813,280	2,263,977	1,559,765
Granted (in shares)	591,369	809,500	765,000
Exercised (in shares)	(19,213)	(55,000)	(47,857)
Forfeited (in shares)	(874,210)	(196,054)	0
Expired (in shares)	(19,047)	(9,143)	(12,931)
Outstanding - end of year (in shares)	2,492,179	2,813,280	2,263,977
Exercisable at end of year (in shares)	1,701,445	1,811,320	1,336,694
Weighted average fair value of stock options granted during the year (in dollars per share)	$ 1.47	$ 2.58	$ 11.28
Weighted-Average Exercise Price Options [Abstract]
Outstanding - beginning of year (in dollars per share)	14.14	18.66	16.98
Granted (in dollars per share)	1.87	3.54	15.66
Exercised (in dollars per share)	2.58	12.84	12.30
Forfeited (in dollars per share)	13.11	20.94	0
Expired (in dollars per share)	56.88	48.18	33.48
Outstanding - end of year (in dollars per share)	11.35	14.14	18.66
Exercisable at end of year (in dollars per share)	$ 14.85	$ 17.70	$ 20.70
Warrants [Member]
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding - beginning of year (in shares)	5,417,155	1,204,245	1,224,960
Granted (in shares)	584,554	5,284,263	0
Exercised (in shares)	(861,581)	(9,393)	(1,667)
Forfeited (in shares)	0	0	0
Expired (in shares)	(1,159,347)	(1,061,960)	(19,048)
Outstanding - end of year (in shares)	3,980,781	5,417,155	1,204,245
Exercisable at end of year (in shares)	3,626,613	5,031,715	1,204,245
Weighted average fair value of stock options granted during the year (in dollars per share)	$ 1.65	$ 1.56	$ 0
Weighted-Average Exercise Price Options [Abstract]
Outstanding - beginning of year (in dollars per share)	4.08	25.68	25.62
Granted (in dollars per share)	6.31	3.72	0
Exercised (in dollars per share)	3.66	4.20	15
Forfeited (in dollars per share)	0	0	0
Expired (in dollars per share)	4.92	26.88	22.92
Outstanding - end of year (in dollars per share)	4.26	4.08	25.68
Exercisable at end of year (in dollars per share)	$ 4.23	$ 4.02	$ 25.68
Issuance of stock options to certain consultants in exchange for services	$ 41,865	$ 157,797
Restricted Stock [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Share based compensation arranged by share based payment award restricted stock granted (in shares)			0
Restricted Stock [Member] | Chairman and Chief Executive Officer [Member]
Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract]
Vesting period	3 years	3 years
Share based compensation arranged by share based payment award restricted stock granted (in shares)	387,597	387,597
Share based compensation of fair value of the restricted stock on the grant	$ 679,000	$ 1,000,000
2000 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	233,334
Expiration date	Aug. 6, 2010
Share-based compensation, shares available for future grant (in shares)	0
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding - end of year (in shares)	44,371
2008 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	5,000,000
Share-based compensation, shares available for future grant (in shares)	1,200,000
Number of Options (Employees and Non-Employees) [Abstract]
Outstanding - end of year (in shares)	2,800,000
2008 Stock Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, outstanding stock options (in shares)	800,000

Stock Options and Equity-Clas47

Stock Options and Equity-Classified Warrants, Schedule of Employee and Non Employee Service Share Based Compensation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employees [Member]
Total stock-based compensation expense resulting from stock options and warrants [Abstract]
Allocated employee and non-employee stock-based compensation expense, Total	$ 2,459,044	$ 6,484,303	$ 7,158,804
Non-Employees [Member]
Total stock-based compensation expense resulting from stock options and warrants [Abstract]
Allocated employee and non-employee stock-based compensation expense, Total	422,000	235,764	225,852
Research and Development Expense [Member] | Employees [Member]
Total stock-based compensation expense resulting from stock options and warrants [Abstract]
Allocated employee and non-employee stock-based compensation expense, Total	549,315	1,822,508	1,590,267
Research and Development Expense [Member] | Non-Employees [Member]
Total stock-based compensation expense resulting from stock options and warrants [Abstract]
Allocated employee and non-employee stock-based compensation expense, Total	11,600	0	0
General and Administrative Expense [Member] | Employees [Member]
Total stock-based compensation expense resulting from stock options and warrants [Abstract]
Allocated employee and non-employee stock-based compensation expense, Total	1,909,729	4,661,795	5,568,537
General and Administrative Expense [Member] | Non-Employees [Member]
Total stock-based compensation expense resulting from stock options and warrants [Abstract]
Allocated employee and non-employee stock-based compensation expense, Total	$ 410,400	$ 235,764	$ 225,852

Stock Options and Equity-Clas48

Stock Options and Equity-Classified Warrants, Options by Exercise Price Range (Details)	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Stock Options [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Number of Options (in shares) | shares	2,865,512
Weighted-Average Remaining Contractual Life	7 years 10 months 10 days
Weighted-Average Exercise Price (in dollars per share)	$ 10.62
Number of Options Exercisable (in shares) | shares	2,074,778
Weighted-Average Contractual Life	7 years 3 months 14 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 13.21
Warrants [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Number of Options (in shares) | shares	3,980,781
Weighted-Average Remaining Contractual Life	8 months 26 days
Weighted-Average Exercise Price (in dollars per share)	$ 4.26
Number of Options Exercisable (in shares) | shares	3,626,613
Weighted-Average Contractual Life	9 months
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 4.23
Range $1.50 - 1.75 [Member] | Stock Options [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	1.50
Range of Exercise Prices, Upper Range (in dollars per share)	$ 1.75
Number of Options (in shares) | shares	829,702
Weighted-Average Remaining Contractual Life	9 years 11 months 16 days
Weighted-Average Exercise Price (in dollars per share)	$ 1.75
Number of Options Exercisable (in shares) | shares	400,000
Weighted-Average Contractual Life	9 years 11 months 16 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 1.75
Range $1.76 - 11.0 [Member] | Stock Options [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	1.76
Range of Exercise Prices, Upper Range (in dollars per share)	$ 11
Number of Options (in shares) | shares	720,970
Weighted-Average Remaining Contractual Life	7 years 11 months 23 days
Weighted-Average Exercise Price (in dollars per share)	$ 4.76
Number of Options Exercisable (in shares) | shares	469,910
Weighted-Average Contractual Life	7 years 5 months 19 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 5.92
Range $11.01 - 15.00 [Member] | Stock Options [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	11.01
Range of Exercise Prices, Upper Range (in dollars per share)	$ 15
Number of Options (in shares) | shares	776,290
Weighted-Average Remaining Contractual Life	7 years 2 months 12 days
Weighted-Average Exercise Price (in dollars per share)	$ 13.92
Number of Options Exercisable (in shares) | shares	667,290
Weighted-Average Contractual Life	7 years 25 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 13.80
Range $15.01 - 195.30 [Member] | Stock Options [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	15.01
Range of Exercise Prices, Upper Range (in dollars per share)	$ 195.30
Number of Options (in shares) | shares	538,550
Weighted-Average Remaining Contractual Life	5 years 5 months 8 days
Weighted-Average Exercise Price (in dollars per share)	$ 27.36
Number of Options Exercisable (in shares) | shares	537,578
Weighted-Average Contractual Life	5 years 5 months 5 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 27.36
Range $3.00 - 6.00 [Member] | Warrants [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	3
Range of Exercise Prices, Upper Range (in dollars per share)	$ 6
Number of Options (in shares) | shares	3,252,137
Weighted-Average Remaining Contractual Life	7 months 6 days
Weighted-Average Exercise Price (in dollars per share)	$ 3.19
Number of Options Exercisable (in shares) | shares	2,918,803
Weighted-Average Contractual Life	7 months 13 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 3.08
Range $6.01 - 9.00 [Member] | Warrants [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	6.01
Range of Exercise Prices, Upper Range (in dollars per share)	$ 9
Number of Options (in shares) | shares	500,000
Weighted-Average Remaining Contractual Life	1 year 25 days
Weighted-Average Exercise Price (in dollars per share)	$ 6.60
Number of Options Exercisable (in shares) | shares	500,000
Weighted-Average Contractual Life	1 year 25 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 6.60
Range $9.01 - 12.00 [Member] | Warrants [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	9.01
Range of Exercise Prices, Upper Range (in dollars per share)	$ 12
Number of Options (in shares) | shares	83,335
Weighted-Average Remaining Contractual Life	3 years 1 month 10 days
Weighted-Average Exercise Price (in dollars per share)	$ 10.44
Number of Options Exercisable (in shares) | shares	62,501
Weighted-Average Contractual Life	3 years 1 month 10 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 10.44
Range $12.01 - 33.60 [Member] | Warrants [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Range of Exercise Prices, Lower Range (in dollars per share)	12.01
Range of Exercise Prices, Upper Range (in dollars per share)	$ 33.60
Number of Options (in shares) | shares	145,309
Weighted-Average Remaining Contractual Life	1 year 2 months 8 days
Weighted-Average Exercise Price (in dollars per share)	$ 16.65
Number of Options Exercisable (in shares) | shares	145,309
Weighted-Average Contractual Life	1 year 2 months 8 days
Weighted-Average Exercise Price, Options Exercisable (in dollars per share)	$ 16.65

Stock Options and Equity-Clas49

Stock Options and Equity-Classified Warrants, Warrants, Shares Purchased and Intrinsic Value (Details) - USD ($)	Jul. 31, 2017	Jul. 28, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jul. 27, 2017	Dec. 16, 2016	Dec. 15, 2016	Feb. 29, 2016	Feb. 05, 2016
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Aggregate intrinsic value of outstanding options			$ 0
Aggregate intrinsic value of options vested			0
Aggregate intrinsic value of options exercised			$ 0
Warrants exercise price (in dollars per share)			$ 30				$ 3.06	$ 4.20
Consultant [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Contingent warrant period				18 months
Warrants exercise price (in dollars per share)				$ 4.20
Number of warrants issued (in shares)				333,334
NantCell, Inc [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Warrants exercise price (in dollars per share)						$ 6.60
Number of warrants issued (in shares)						500,000
Hercules Capital, Inc. and Hercules Technology III, L.P. [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Percentage of stock issuable upon exercise of the warrants	80.00%	80.00%
Warrants [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Warrants exercise price (in dollars per share)									$ 10.44
Number of warrants issued (in shares)									83,334
Non-employee stock-based compensation expenses			$ 41,865	$ 157,797
Warrants [Member] | NantCell, Inc [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Number of warrants issued (in shares)	500,000
Warrants [Member] | Hercules Capital, Inc. and Hercules Technology III, L.P. [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Warrants exercise price (in dollars per share)	$ 4.62	$ 4.62								$ 12.30
Warrants outstanding (in shares)	84,554
Number of warrants issued (in shares)										105,691
Fair value of warrants classified as equity warrants			633,749	633,749
Restricted Stock [Member]
Share based compensation, shares authorized under significant ranges of outstanding stock option plans in period [Abstract]
Restricted stock expense			$ 344,000	$ 15,000	$ 0

Stockholder Protection Rights50

Stockholder Protection Rights Plan (Details)	12 Months Ended
	Dec. 31, 2017Right$ / shares	Dec. 16, 2016$ / shares	Dec. 15, 2016$ / shares
Stockholder Protection Rights Plan [Abstract]
Number of right for each outstanding share | Right	1
Proportion of right entitles to purchase series A preferred stock	0.0001
Exercise price of warrants (in dollars per share) | $ / shares	$ 30	$ 3.06	$ 4.20
Number of business days after announcement rights are not exercisable for certain persons	10 days
Beneficial ownership percentage of company outstanding shares of common stock by acquiring person	15.00%
Percentage of company outstanding shares of common stock by acquiring person	50.00%

Income Taxes (Details)

Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Deferred tax valuation allowance has been recorded against these assets		100.00%
Federal corporate tax rate		35.00%
Remeasurement of deferred tax assets and liabilities, deferred tax expense		$ 27,300,000
Deferred tax assets [Abstract]
Net operating loss carryforwards		66,251,000	$ 126,244,000
Tax credit carryforwards		33,899,000	29,970,000
Equipment, furnishings and other		4,909,000	9,297,000
Total deferred tax assets		105,059,000	165,511,000
Deferred tax liabilities		0	(301,000)
Net deferred tax assets		105,059,000	165,210,000
Valuation allowance		(105,059,000)	(165,210,000)
Deferred tax assets, net of valuation allowance		0	0
Net change in valuation allowance		60,200,000	21,400,000
Federal statutory rate to net loss before income taxes [Abstract]
Federal benefit at statutory rate		(11,895,000)	(17,262,000)	$ (19,919,000)
State income taxes, net of Federal taxes		(2,073,000)	(3,086,000)	(3,556,000)
State credits		(506,000)	(1,031,000)	(1,324,000)
Warranty liabilities		(465,000)	(1,301,000)	(1,509,000)
Other permanent differences		11,000	40,000	16,000
Provision related to change in valuation allowance		(60,358,000)	21,601,000	20,142,000
Federal rate adjustment		27,314,000	0	0
NQ Options		47,000	0	0
Current year tax credit		(665,000)	(1,119,000)	(2,050,000)
NOL Adjustments		45,521,000	0	0
Termination/Cancellation of Equity Compensation Awards		2,983,000	2,274,000	5,960,000
Return to provision		84,000	(118,000)	2,238,000
Other, net		3,000	3,000	3,000
Provision for income taxes		800	800	800
Change in unrecognized tax benefits		0
Unrecognized tax benefits accrued interest or penalties		$ 0	$ 0	$ 0
Plan [Member]
Operating Loss Carryforwards [Line Items]
Federal corporate tax rate	21.00%
Earliest Tax Year [Member]
Operating Loss Carryforwards [Line Items]
Expiration Date		Dec. 31, 2022
Latest Tax Year [Member]
Operating Loss Carryforwards [Line Items]
Expiration Date		Dec. 31, 2037
Federal [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards		$ 373,700,000
Federal [Member] | Restricted [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards		136,800,000
Federal [Member] | Unrestricted [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards		236,900,000
Federal [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward [Line Items]
Tax credit carryforward		16,600,000
State [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards		236,300,000
State [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward [Line Items]
Tax credit carryforward		$ 21,900,000

Quarterly Financial Data (una52

Quarterly Financial Data (unaudited) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Data [Abstract]
Total revenues	$ 100,000	$ 0	$ 0	$ 0	$ 100,000	$ 0	$ 100,000	$ 0
Net loss	$ (4,460,000)	$ (5,124,000)	$ (14,358,000)	$ (11,044,000)	$ (7,672,000)	$ (12,175,000)	$ (18,280,000)	$ (12,643,000)	$ (34,986,432)	$ (50,771,221)	$ (58,587,190)
Basic and diluted loss per share applicable to common stock (in dollars per share)	$ (0.16)	$ (1.14)	$ (0.60)	$ (0.60)	$ (0.48)	$ (0.78)	$ (1.62)	$ (1.14)	$ (1.46)	$ (3.78)	$ (5.82)

SCHEDULE II - VALUATION AND Q53

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - Allowance for Deferred Tax Assets [Member] - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 165,210,000	$ 143,609,000	$ 123,466,000
Additions Charged to Costs and Expenses	0	0	0
Additions Charged to Other Accounts	(60,151,000)	21,601,000	20,143,000
Deductions	0	0	0
Balance at End of Year	$ 105,059,000	$ 165,210,000	$ 143,609,000