Mustang Bio (MBIO) 10-K 31 Mar 17 2016 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2016	Mar. 30, 2017	Jun. 30, 2016
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Entity Registrant Name	MUSTANG BIO, INC.
Entity Central Index Key	1,680,048
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	Non-accelerated Filer
Entity Public Float			$ 0
Entity Common Stock, Shares Outstanding		24,976,289

BALANCE SHEETS

BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current Assets:
Cash	$ 27,499	$ 0
Total current assets	27,499	0
Total Assets	27,499	0
Current Liabilities:
Accounts payable and accrued expenses	683	15
Common shares issuable liability	1,682	0
Accrued expenses - related party	125	375
Accrued interest - related party	413	168
Notes payable - related party	320	3,571
Total current liabilities	3,223	4,129
Total Liabilities	3,223	4,129
Commitments and Contingencies
Stockholders' Equity (Deficit)
Preferred stock ($0.0001 par value), 2,000,000 shares authorized, 250,000 and 0 shares of Class A preferred stock issued and outstanding as of December 31, 2016 and December 31, 2015, respectively	0	0
Common Stock, Value, Issued	2	0
Common stock issuable, 767,264 and 250,000 shares as of December 31, 2016 and December 31, 2015, respectively	4,396	190
Additional paid-in capital	36,998	146
Accumulated deficit	(17,120)	(4,466)
Total Stockholders’ Equity (Deficit)	24,276	(4,129)
Total Liabilities and Stockholders’ Equity	27,499	0
Common Class A [Member]
Stockholders' Equity (Deficit)
Common Stock, Value, Issued	0	0
Total Stockholders’ Equity (Deficit)	0	0
Common Class B [Member]
Stockholders' Equity (Deficit)
Common Stock, Value, Issued	0	1
Total Stockholders’ Equity (Deficit)	$ 0	$ 1

BALANCE SHEETS (Parenthetical)

BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Preferred Stock, Par or Stated Value Per Share	$ 0.0001	$ 0.0001
Preferred Stock, Shares Authorized	2,000,000	2,000,000
Common Stock, Par or Stated Value Per Share	$ 0.0001	$ 0.0001
Common Stock, Shares Authorized	50,000,000	50,000,000
Common Stock, Shares, Issued	15,165,244	2,000,000
Common Stock, Shares, Outstanding	15,165,244	2,000,000
Common Stock, Shares Subscribed but Unissued	767,264	250,000
Series A Preferred Stock [Member]
Preferred Stock, Shares Issued	250,000	0
Preferred Stock, Shares Outstanding	250,000	0
Common Class A [Member]
Common Stock, Shares, Issued	1,000,000	1,000,000
Common Stock, Shares, Outstanding	1,000,000	1,000,000
Common Class B [Member]
Common Stock, Shares, Issued	0	7,000,000
Common Stock, Shares, Outstanding	0	7,000,000

STATEMENTS OF OPERATIONS

STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	10 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016
Operating expenses:
Research and development	$ 1,707	$ 2,468
Research and development - licenses acquired	2,337	6,079
General and administrative	254	2,816
Total operating expenses	4,298	11,363
Loss from operations	4,298	11,363
Other income (expense)
Interest income	0	16
Interest expense - related party	(168)	(253)
Interest expense	0	(895)
Change in fair value of derivative warrant liabilities	0	(159)
Total other expense	(168)	(1,291)
Net Loss	$ (4,466)	$ (12,654)
Net loss per common share outstanding, basic and diluted	$ (0.45)	$ (1.15)
Weighted average number of common shares outstanding, basic and diluted	9,993,197	11,026,666

STATEMENTS OF STOCKHOLDERS' EQU

STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Preferred Stock Class A [Member]	Common Shares Class A [Member]	Common Shares Class B [Member]	Common Shares [Member]	Common Stock Issuable [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Balances, Begining at Mar. 12, 2015
Balance, Begining (in shares) at Mar. 12, 2015
Issuance of Class B common shares to Fortress on March 13, 2015		0	0	7,000,000	0
Issuance of Class B common shares to Fortress on March 13, 2015 (in shares)	$ 0	$ 0	$ 0	$ 1	$ 0	$ 0	$ (1)	$ 0
Issuance of common shares - Founders Agreement	147	$ 0	$ 0	$ 0	$ 0	0	147	0
Issuance of common shares - Founders Agreement (in shares)		0	1,000,000	0	0
Issuance of common shares to Fortress on March 13, 2015		0	0	0	2,000,000
Issuance of common shares to Fortress on March 13, 2015 (in shares)	0	$ 0	$ 0	$ 0	$ 0	0	0	0
Common stock issuable - Founders Agreement	190	0	0	0	0	190	0	0
Net loss	(4,466)	0	0	0	0	0	0	(4,466)
Balances, Ending at Dec. 31, 2015	(4,129)	$ 0	$ 0	$ 1	$ 0	190	146	(4,466)
Balances Ending (in shares) at Dec. 31, 2015		0	1,000,000	7,000,000	2,000,000
Issuance of common shares - Founders Agreement	862	$ 0	$ 0	$ 0	$ 0	(190)	1,052	0
Issuance of common shares - Founders Agreement (in shares)		0	0	250,000	150,370
Issuance of common shares and warrants for cash	39,098	$ 0	$ 0	$ 0	$ 1	0	39,097	0
Issuance of common shares and warrants for cash (in shares)		0	0	0	6,014,874
Common stock issuable - Founders Agreement	4,396	$ 0	$ 0	$ 0	$ 0	4,396	0	0
Offering cost	(4,090)	0	0	0	0	0	(4,090)	0
Issuance of warrants - NSC Note	793						793
Exchange of Class A Preferred Stock and common stock	0	$ 0	$ 0	$ (1)	$ 1	0	0	0
Exchange of Class A Preferred Stock and common stock (in shares)		250,000	0	(7,250,000)	7,000,000
Net loss	(12,654)	$ 0	$ 0	$ 0	$ 0	0	0	(12,654)
Balances, Ending at Dec. 31, 2016	$ 24,276	$ 0	$ 0	$ 0	$ 2	$ 4,396	$ 36,998	$ (17,120)
Balances Ending (in shares) at Dec. 31, 2016		250,000	1,000,000	0	15,165,244

STATEMENTS OF CASH FLOWS

STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	10 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016
Cash flows from operating activities:
Net loss	$ (4,466)	$ (12,654)
Common shares issuable for license acquired	147	1,682
Research and development-licenses acquired, expensed	2,000	0
Issuance of common shares - Founders Agreement	0	862
Common shares issuable for Founders Agreement	190	4,396
Debt discount amortization	0	763
Change in fair value of derivative warrant liabilities	0	159
Changes in operating assets and liabilities:
Accounts payable and accrued expenses	15	668
Accrued expenses - related party	375	(250)
Accrued interest - related party	168	245
Net cash used in operating activities	(1,571)	(4,129)
Cash Flows from Investing Activities:
Purchase of research and development licenses	(2,000)	0
Net cash used in investing activities	(2,000)	0
Cash Flows from Financing Activities:
Proceeds from Fortress Note	3,571	2,221
Payment of Fortress Note	0	(2,001)
Payment of NSC Note	0	(3,600)
Proceeds from issuance of common stock and warrants, net of offering cost of $4,090 and $0, respectively	0	35,008
Net cash provided by financing activities	3,571	31,628
Net change in cash	0	27,499
Cash, beginning of the period	0	0
Cash, end of the period	0	27,499
Supplemental disclosure of cash flow information:
Cash paid for interest	0	140
Supplemental disclosure of noncash investing and financing activities:
Issuance of common shares - Founders Agreement	1	190
Warrant liability associated with NCS Note	0	793
Exchange of Class A preferred stock and common stock	0	1
Transfer from Fortress of NSC Note, net of discount of $129 and $0, respectively	$ 0	$ 3,471

STATEMENTS OF CASH FLOWS (Paren

STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Proceeds from issuance of common stock and warrants, offering cost	$ 4,090	$ 0
NSC Note [Member]
Debt Instrument, Unamortized Discount	$ 129	$ 0

Organization and Plan of Busine

Organization and Plan of Business Operations	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Mustang Bio, Inc. (the “Company” or “Mustang”) was incorporated in Delaware on March 13, 2015, as a majority-owned subsidiary of Fortress Biotech, Inc. (“Fortress” or “Parent”) and commenced its principal operations on March 13, 2015. Mustang was formed as a clinical-stage biopharmaceutical company focused on the acquisition, development and commercialization of novel cancer immunotherapy products designed to utilize the power of the patient’s own immune system to eliminate cancer cells. The Company may acquire rights to these technologies by licensing the rights or otherwise acquiring an ownership interest in the technologies, funding their research and development and eventually either out-licensing or bringing the technologies to market. Chimeric Antigen Receptor (CAR) engineered T-cells (CAR-T) technology In March 2015, Mustang entered into an exclusive license and sponsored research agreement with the City of Hope National Medical Center (“COH”), collectively referred to as “COH Agreements”, to acquire CAR-T. CAR-T uses the patient’s own T-cells to engage and destroy specific tumors. The process involves selecting specific T-cell subtypes, genetically engineering them to express chimeric antigen T cell receptors and placing them back in the patient where they recognize and destroy cancer cells. The exclusive license agreement covers the discovery, manufacture and clinical development of novel CAR-T along with specified rights to any and all inventions. On February 17, 2017, the Company and COH amended and restated the Original Agreement in connection with the covered patents by entering into three separate amended and restated exclusive license agreements, one relating to CD123, one relating to IL-13 and one relating to the spacer technology, that amended the Original Agreement in certain other respects, and collectively replace the Original Agreement in its entirety. The total potential consideration payable to COH by the Company, in equity or cash, did not, in the aggregate, change materially from the Original Agreement.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	Note 2 — Significant Accounting Policies The Company’s financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The Company has no subsidiaries. The financial statements may not be indicative of future performance and may not reflect what the Company’s results of operations, financial position, and cash flows would have been had Mustang operated as an independent entity. Certain estimates have been made to provide financial statements for stand-alone reporting purposes. All inter-company transactions between Fortress and Mustang are classified as due to related party in the financial statements. The Company believes that the assumptions underlying the financial statements are reasonable. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates. The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. There were no cash equivalents at December 31, 2016 and 2015. Research and development costs are expensed as incurred. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. Upfront and milestone payments due to third parties that perform research and development services on the Company’s behalf will be expensed as services are rendered or when the milestone is achieved. Research and development costs primarily consist of personnel related expenses, including salaries, benefits, travel, and other related expenses, stock-based compensation, payments made to third parties for license and milestone costs related to in-licensed products and technology, payments made to third party contract research organizations for preclinical and clinical studies, investigative sites for clinical trials, consultants, the cost of acquiring and manufacturing clinical trial materials, costs associated with regulatory filings, laboratory costs and other supplies. Costs incurred in obtaining technology licenses are charged to research and development expense if the technology licensed has not reached commercial feasibility and has no alternative future use. The licenses purchased by the Company require substantial completion of research and development, regulatory and marketing approval efforts in order to reach commercial feasibility and has no alternative future use. Accordingly, the total purchase price for the licenses acquired is reflected as research and development – licenses acquired on the Company’s Statements of Operations. Prior to the July 2016 amendment to the Founder’s Agreement, Fortress was entitled to an annual fee on each anniversary date equal to 2.5 The Company recorded the Annual Equity Fee in connection with the Founders Agreement with Mustang as contingent consideration. Contingent consideration is recorded when probable and reasonably estimable. The Company’s future share prices cannot be estimated due to the nature of its assets and the Company’s stage of development. Due to these uncertainties, the Company concluded that it could not reasonably estimate the contingent consideration until shares were actually issued on March 13, 2016. Because the issuance of shares on March 13, 2016 occurred prior to the issuance of the December 31, 2015 financial statements, the Company recorded approximately $ 190,000 In July 2016, in connection with the Amended and Restated Articles of Incorporation, the Company issued 250,000 2.5 The Company recorded the Annual Stock Dividend due Fortress as contingent consideration. Contingent consideration is recorded when probable and reasonably estimable. The Company’s future share prices cannot be estimated due to the nature of its assets and the Company’s stage of development. Due to these uncertainties, the Company concluded that it could not reasonably estimate the contingent consideration until shares were actually issued on March 13, 2017. Because the issuance of shares on March 13, 2017 occurred prior to the issuance of the December 31, 2016 financial statements, the Company recorded approximately $ 4.4 The Company follows accounting guidance on fair value measurements for financial assets and liabilities measured at fair value on a recurring basis. Under the accounting guidance, fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. The accounting guidance requires fair value measurements be classified and disclosed in one of the following three categories: Level 1: Quoted prices in active markets for identical assets or liabilities. Level 2: Observable inputs other than Level 1 prices, for similar assets or liabilities that are directly or indirectly observable in the marketplace. Level 3: Unobservable inputs which are supported by little or no market activity and that are financial instruments whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. In accordance with ASC 815, the Company classified the fair value of the warrant (“Contingently Issuable Warrants”) that may have been granted in connection with the NSC Note transferred to the Company in various tranches from July 5, 2016 to October 25, 2016 as a derivative liability as there was a potential that the Company would not have a sufficient number of authorized common shares available to settle this instrument. The Company valued these Contingently Issuable Warrants using an option pricing model (which approximates intrinsic value) with estimates for an expected dividend yield, a risk-free interest rate, and expected volatility together with management’s estimate of the probability of issuance of the Contingently Issuable Warrants. At each reporting period, as long as the Contingently Issuable Warrants were potentially issuable and there was a potential for an insufficient number of authorized shares available to settle the Contingently Issuable Warrants, the Contingently Issuable Warrants should be revalued and any difference from the previous valuation date would be recognized as a change in fair value in the Company’s Statement of Operations. The Company accounts for potential shares that can be converted to common stock and if converted, will be in excess of authorized shares, as a liability that is recorded on the balance sheet (at fair value) only until the authorized number of shares is increased (at which time the whole liability will be re-measured, with changes in value included in other income/(expense), and then reclassified to additional paid-in capital). The value of the liability was computed by valuing the securities that management believed were most likely to be converted. This liability is revalued at each reporting date with any change in value included in other income / (expense) until such time as enough shares are authorized to cover all potentially convertible instruments For purposes of these financial statements, the Company’s income tax expense and deferred tax balances have been recorded as if it filed tax returns on a stand-alone basis separate from Fortress. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities measured at the enacted tax rates in effect for the year in which these items are expected to reverse. Deferred tax assets are reduced by valuation allowances if, based on the consideration of all available evidence, it is more likely than not that some portion or all of the deferred tax asset will not be realized. Net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period. Since dividends are declared, paid and set aside among the holders of shares of common stock and Class A Common Stock pro-rata on an as-if-converted basis, the two-class method of computing net loss per share is not required. Diluted net loss per share does not reflect the effect of shares of common stock to be issued upon the exercise of warrants or outstanding Class A preferred shares, as their inclusion would be anti-dilutive. There are 2,243,664 250,000 The Company expenses stock-based compensation to employees over the requisite service period based on the estimated grant-date fair value of the awards and forfeiture rates. For stock-based compensation awards to non-employees, the Company re-measures the fair value of the non-employee awards at each reporting period prior to vesting and finally at the vesting date of the award. Changes in the estimated fair value of these non-employee awards are recognized as stock-based compensation expense in the period of change. In January 2017, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2017-04, Intangibles - Goodwill and Other In January 2017, FASB issued ASU 2017-01, “ Business Combinations (Topic 805) Clarifying the Definition of a Business In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments In April 2016, the FASB issued ASU 2016-10, Revenue from Contracts with Customer (“ASU 2016-10”) In March 2016, the FASB issued ASU 2016-09 Compensation-Stock Compensation (Topic 718), Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”) In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) Leases (Topic 840) In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements-Going Concern

COH Agreements

COH Agreements	12 Months Ended
	Dec. 31, 2016
License Agreement Disclosure [Abstract]
License Agreement Disclosure [Text Block]	Note 3 – COH Agreements The CAR-T Agreements City of Hope On March 17, 2015, the Company entered into an exclusive license agreement with COH to acquire intellectual property rights pertaining to CAR-T (the “Original Agreement”). Pursuant to the agreement, the Company paid COH an upfront fee of $ 2.0 1,000,000 10 The Company valued the stock grant to COH utilizing a discounted cash flow model to determine the weighted market value of invested capital, discounted by a lack of marketability of 44.8 30 0.147 147,000 research and development-licenses acquired expenses In February 2017, COH was granted 293,588 5.73 1.7 77.0 1.93 10 10.0 In addition, the Company entered into a sponsored research agreement with COH in which the Company will fund continued research in the amount of $ 2.0 2.0 1.5 60,000 60,000 1,000,000 6.1 10 Fortress From March 13, 2015 (inception) through December 31, 2015, in accordance with the Original Founders Agreement, the Company issued 250,000 0.147 36,750 4.4 767,264 5.73

Related Party Agreements

Related Party Agreements	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	Note 4 – Related Party Agreements Founders Agreement and Management Services Agreement with Fortress Effective March 13, 2015, the Company entered a Founders Agreement with Fortress, which was amended and restated on May 17, 2016 and again on July 26, 2016 (the “Mustang Founders Agreement”). The Mustang Founders Agreement provides that, in exchange for the time and capital expended in the formation of Mustang and the identification of specific assets the acquisition of which result in the formation of a viable emerging growth life science company, Fortress loaned $ 2.0 15 7.25 7.0 250,000 Each share of Class A Preferred Stock is convertible, at Fortress’ option, into one fully paid and nonassessable share of Mustang common stock, subject to certain adjustments. As holders of Class A Preferred Stock, Fortress will receive on each March 13 (each a “PIK Dividend Payment Date”) until the date all outstanding Class A Preferred Stock is converted into common stock or redeemed (and the purchase price is paid in full), pro rata per share dividends paid in additional fully paid and nonassessable shares of common stock (“PIK Dividends”) such that the aggregate number of shares of common stock issued pursuant to such PIK Dividend is equal to two and one-half percent (2.5%) of Mustang’s fully-diluted outstanding capitalization on the date that is one (1) business day prior to any PIK Dividend Payment Date. As additional consideration under the Mustang Founders Agreement, Mustang will also: (i) pay an equity fee in shares of common stock, payable within five (5) business days of the closing of any equity or debt financing for Mustang or any of its respective subsidiaries that occurs after the effective date of the Mustang Founders Agreement and ending on the date when Fortress no longer has majority voting control in the Company’s voting equity, equal to two and one-half (2.5%) of the gross amount of any such equity or debt financing; and (ii) pay a cash fee equal to four and one-half percent (4.5%) of the Company’s annual net sales, payable on an annual basis, within ninety (90) days of the end of each calendar year. In the event of a Change in Control, the Company will pay a one-time change in control fee equal to five (5x) times the product of (A) net sales for the twelve (12) months immediately preceding the change in control and (B) four and one-half percent (4.5%). On March 13, 2016, pursuant to the then in effect Mustang Founders Agreement, on the anniversary date of the Founders’ Agreement, the Company issued 250,000 2.5 Effective as of March 13, 2015, the Company entered into a Management Services Agreement (the “MSA”) with Fortress. Pursuant to the terms of the MSA, for a period of five years, Fortress will render advisory and consulting services to the Company. Services provided under the MSA may include, without limitation, (i) advice and assistance concerning any and all aspects of the Company’s operations, clinical trials, financial planning and strategic transactions and financings and (ii) conducting relations on behalf of the Company with accountants, attorneys, financial advisors and other professionals (collectively, the “Services”). The Company is obligated to utilize clinical research services, medical education, communication and marketing services and investor relations/public relation services of companies or individuals designated by Fortress, provided those services are offered at market prices. However, the Company is not obligated to take or act upon any advice rendered from Fortress and Fortress shall not be liable for any of its actions or inactions based upon their advice. Fortress and its affiliates, including all members of the Company’s Board of Directors, have been contractually exempt from fiduciary duties to the Company relating to corporate opportunities. In consideration for the Services, the Company will pay Fortress an annual consulting fee of $ 0.5 1.0 100 500,000 375,000 Consulting Agreement with Chord Advisors, LLC (“Chord”) On April 8, 2016, the Company entered into a full service consulting agreement with Chord to provide advisory accounting services to the Company. Under the terms of the agreement, the Company paid Chord up to $ 5,000 7,500 48,000 Fortress Note The Company has a working capital promissory note with Fortress (see Note 5). NSC Note and Financings In September 2016, Fortress acquired through a tender offer 56.6 3.6 10 In September 2016, the Company entered into a Placement Agent Agreement with National in connection with financing in which the Company agreed to pay NSC a cash fee of 10.0 25 3.6 601,486

Notes Payable

Notes Payable	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Debt Disclosure [Text Block]	Note 5 - Notes Payable Fortress Note In 2015, the Company and Fortress entered into an Intercompany Working Capital Promissory Note (“Fortress Note”), in which Fortress agreed to provide a working capital line of credit to the Company from inception through a third party financing. The Fortress Note is due on demand and accrues interest of 8 At December 31, 2016, the Fortress Note was approximately $ 320,000 253,000 168,000 The Fortress Note was paid in full during the first quarter of 2017. NSC Note In March 2015, Fortress closed a private placement of a promissory note for $ 10 The NSC Note was amended and restated on July 29, 2015, to provide that any time a Fortress Company receives from Fortress any proceeds from the NSC Note, Fortress may, in its sole discretion, cause the Fortress Company to issue to NSC Biotech Venture Fund I LLC a new promissory note (the “Amended NSC Note”) on identical terms as the NSC Note (giving effect to the passage of time with respect to maturity). The Amended NSC Note will equal the dollar amount of the Fortress Company’s share of the NSC Note and reduce the Fortress’ obligations under the NSC Note by such amount. Fortress will guarantee the Amended NSC Note until the Company completes an initial public offering. If the Company has an initial public offering and raises sufficient equity capital so that it has cash equal to five times the amount of the portion of the proceeds of the NSC Note transferred to it, then NSC will receive a warrant to purchase the Company’s stock equal to 25 10 On July 5, 2016, Fortress transferred $ 3.6 129,000 25 763,000 140,000 8 23.1 634,000 Pursuant to the terms of the Company’s $ 3.6 138,462 NSC Note Payable Discount NSC Note Payable, Net January 1, 2016 balance $ - $ - $ - Proceeds from issuance of NSC Note 3,600 (129) 3,471 Issuance of warrants in conjunction with NSC debt - (634) (634) Amortization of debt discount - 192 192 Payoff of note (3,600) 571 (3,029) December 31, 2016 balance $ - $ - $ -

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value, Measurement Inputs, Disclosure [Text Block]	Note 6 - Fair Value Measurement Financial instruments measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Contingently Issuable Warrants Fair value, January 1, 2016 $ - Warrant liability associated with NCS debt 634 Change in fair value 159 Issuance of 138,462 warrants with a par value strike price (793) Fair value, December 31, 2016 $ - If the Company has an initial public offering and raises sufficient equity capital so that it has cash equal to five times the amount of the portion of the proceeds of the NSC Note transferred to it, then NSC will receive a warrant to purchase the Company’s stock equal to 25% of the outstanding note divided by the lowest price the Company sells its equity in its first third party financing. In the fourth quarter of 2016, due to the financings described in Note 8, sufficient equity capital was raised so that the Company had cash equal to five times the amount of the portion of the proceeds of the NSC Note transferred to it. The Company issued 138,462 ten year term The Company's liability for common shares issuable liability was measured using significant unobservable (Level 3) inputs. ($ in thousands): Year Ended December 31, 2016 Beginning Balance $ - Liabilities reclassified 1,682 Change in value of liabilities reclassified - Liabilities reclassified to equity - Ending Balance $ 1,682

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	Note 7 – Commitments and Contingencies Leases The Company is not a party to any leases for office space or equipment. Litigation On January 15, 2016, Dr. Winson Tang (“Plaintiff”) filed a Complaint against the Company in the Superior Court of the State of California, County of Los Angeles. Winson Tang v. Lindsay Rosenwald et al, Case No. BC607346. As amended, the complaint alleges that Dr. Tang was a third-party beneficiary of the Company's Exclusive License Agreement with COH and should be declared the owner of 15 Defendants filed their answer on February 23, 2017, denying Tan has any rights to recovery. trial on November 6 As of December 31, 2016, the Company has not accrued any losses in connection with this litigation as the Company believes that Plaintiff's claims are without merit and intends to vigorously defend this lawsuit. Even in the event of an adverse determination, Fortress and the Company intend to satisfy any judgment from sources other than newly issued shares of the Company to prevent dilution.

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit)	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Note [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	Note 8 — Stockholders’ Equity (Deficit) Common Stock The Company, in accordance with its certificate of incorporation, as amended in July 2016, which was retroactively applied, is authorized to issue 50,000,000 0.0001 1,000,000 15,000,000 In connection with the Company’s formation, Fortress subscribed for 7,000,000 2,000,000 900 The holders of Common Stock are entitled to one vote per share of Common Stock held. The holders of Class A Common Stock are entitled to the number of votes equal to the number of whole shares of Common Stock into which the shares of Class A Common Stock held by such holder are convertible and for a period of ten years from its issuance, the holders of the Class A Common Stock have the right to appoint one member of the board of directors of Mustang; to date, the holders of Class A Common Stock have not yet appointed such director. The Class B Common Stockholders are entitled, for each share of Class B Common Stock held, to a number of votes equal to 1.1 Pursuant to the Founders Agreement, on March 13, 2016 the Company issued 250,000 2.5 Class A Common Shares On March 17, 2015, the Company entered into an exclusive license agreement with COH to acquire intellectual property rights pertaining to CAR-T. Pursuant to the agreement, the Company paid COH an upfront fee of $ 2.0 research and development-licenses acquired expenses 1,000,000 10 1,000,000 Exchange of Class B Common Shares and Class A Preferred Shares In accordance with the amended and restated certificate of incorporation filed on July 27, 2016, the Company issued 250,000 7.0 7.2 Offerings and Issuances of Common Stock and Warrants In September 2016, the Company entered into a Placement Agent Agreement with NSC relating to the Company’s offering of shares of Common Stock in a private placement. Pursuant to the Placement Agent Agreement, the Company agreed to pay the Placement Agent a cash fee of 10.0 10 10,000 2,500 8.50 65,000 On September 30, 2016, the Company had an initial closing in which the Company issued 1,914,833 478,708 191,483 12.4 1.4 1.3 On October 25, 2016, the Company closed a second round of financing totaling gross proceeds of $ 7.1 710,000 10 10,000 2,500 8.50 65,000 1,090,580 272,645 109,058 On November 30, 2016, the Company closed a third round of financing totaling gross proceeds of $ 12.4 1.2 10 10,000 2,500 8.50 65,000 1,900,215 475,053 190,021 On December 12, 2016, the Company closed a fourth round of financing totaling gross proceeds of $ 3.1 310,000 10 10,000 2,500 8.50 65,000 477,000 119,250 47,700 On December 29, 2016, the Company closed a fifth round of financing totaling gross proceeds of $ 4.1 410,000 10 10,000 2,500 8.50 65,000 632,246 158,062 63,224 Pursuant to the Founders Agreement, the Company issued 150,370 2.5 862,000 Class A Preferred Shares Pursuant to the Company’s Amended and Restated Articles of Incorporation, filed on July 26, 2016, Class B Common Stock was eliminated and 2,000,000 250,000 The holders of the outstanding shares of Class A Preferred Stock shall receive on each March 13 (each a “PIK Dividend Payment Date”) after the original issuance date of the Class A Preferred Stock until the date all outstanding Class A Preferred Stock is converted into Common Stock or redeemed (and the purchase price is paid in full), pro rata per share dividends paid in additional fully paid and nonassessable shares of Common Stock (such dividend being herein called “PIK Dividends”) such that the aggregate number of shares of Common Stock issued pursuant to such PIK Dividend is equal to 2.5% of the Corporation’s fully-diluted outstanding capitalization on the date that is one business day prior to any PIK Dividend Payment Date (“PIK Record Date”). In the event the Class A Preferred Stock converts into Common Stock, the holders shall receive all PIK Dividends accrued through the date of such conversion. No dividend or other distribution shall be paid, or declared and set apart for payment (other than dividends payable solely in capital stock on the capital stock of the Company) on the shares of Common Stock until all PIK Dividends on the Class A Preferred Stock shall have been paid or declared and set apart for payment. All dividends are non-cumulative. On any matter presented to the stockholders of the Company for their action or consideration at any meeting of stockholders of the Company (or by written consent of stockholders in lieu of meeting), each holder of outstanding shares of Class A Preferred Stock shall be entitled to cast for each share of Class A Preferred Stock held by such holder as of the record date for determining stockholders entitled to vote on such matter, the number of votes that is equal to one and one-tenth (1.1) times a fraction, the numerator of which is the sum of (A) the number of shares of outstanding Common Stock and (B) the whole shares of Common Stock in to which the shares of outstanding Class A Common Stock and the Class A Preferred Stock are convertible, and the denominator of which is number of shares of outstanding Class A Preferred Stock (the “Class A Preferred Stock Ratio”). Thus, the Class A Preferred Stock will at all times constitute a voting majority. Each share of Class A Preferred Stock is convertible, at the option of the holder, into one fully paid and nonassessable share of Common Stock (the “Conversion Ratio”), subject to certain adjustments. If the Company, at any time effects a subdivision or combination of the outstanding Common Stock (by any stock split, stock dividend, recapitalization, reverse stock split or otherwise), the applicable Conversion Ratio in effect immediately before that subdivision is proportionately decreased or increased, as applicable, so that the number of shares of Common Stock issuable on conversion of each share of Class A Preferred Stock shall be increased or decreased, a applicable, in proportion to such increase or decrease in the aggregate number of shares of Common Stock outstanding. Additionally, if any reorganization, recapitalization, reclassification, consolidation or merger involving the Company occurs in which the Common Stock (but not the Class A Preferred Stock) is converted into or exchanged for securities, cash or other property, then each share of Class A Preferred Stock becomes convertible into the kind and amount of securities, cash or other property which a holder of the number of shares of Common Stock of the Company issuable upon conversion of one share of the Class A Preferred Stock immediately prior to such reorganization, recapitalization, reclassification, consolidation or merger would have been entitled to receive pursuant to such transaction. Warrants Weighted Average Weighted Average Remaining Contractual Warrants Exercise Price Life (in years) Outstanding as of January 1, 2016 - $ - - Granted 2,243,664 7.98 - Outstanding as of December 31, 2016 2,243,664 $ 7.98 5.16 Upon the exercise of warrants, the Company will issue new shares of Common Stock.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Note 9 – Income Taxes For financial reporting purposes, the Company calculated income tax provision and deferred income tax balances as if it was a separate entity and had filed its own separate tax return under Sub-chapter C of the Internal Revenue Code. For the years ended December 31, 2016 2015 Statutory federal income tax rate 35 % 35 % State taxes, net of federal tax benefit 13 % 5 % Non-deductible items (3) % (2) % Credits - 1 % Rate change 1 % - Other 1 % - Change in valuation allowance (47) % (39) % Income taxes provision (benefit) - - The components of the net deferred tax asset as of December 31, 2016 and 2015 are the following ($ in thousands): As of December 31, 2016 2015 Deferred tax assets: Net operating loss carryovers $ 3,310 $ 893 Stock compensation and other 301 - Change in warrant liability 76 - Amortization of license 3,848 815 Start up costs 13 - Tax credits 89 38 Total deferred tax assets 7,637 1,746 Less valuation allowance (7,637) (1,746) Deferred tax assets, net of valuation allowance $ - $ - The Company has determined, based upon available evidence, that it is more likely than not that the net deferred tax asset will not be realized and, accordingly, has provided a full valuation allowance against its net deferred tax asset. A valuation allowance of approximately $ 7.6 1.7 As of December 31, 2016, the Company had federal and state net operating loss carryforwards of approximately $ 7.3 13.5 2035 2025 There are no significant items determined to be unrecognized tax benefits taken or expected to be taken in a tax return, in accordance with ASC 740 “Income Taxes” (“ASC 740”), which clarifies the accounting for uncertainty in income taxes recognized in the financial statements, that have been recorded on the Company’s financial statements for the period ended December 31, 2016. The Company does not anticipate a material change to unrecognized tax benefits in the next twelve months. Additionally, ASC 740 provides guidance on the recognition of interest and penalties related to income taxes. There were no interest or penalties related to income taxes that have been accrued or recognized as of and for the period ended December 31, 2016. The federal and state tax returns for the periods ended December 31, 2016 and 2015 are currently open for examination under the applicable federal and state income tax statues of limitations.

Quarterly Financial Date (unaud

Quarterly Financial Date (unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Data [Abstract]
Quarterly Financial Information [Text Block]	Note 10 – Quarterly Financial Date (unaudited) (in thousands, except per share data) First Quarter Second Quarter Third Quarter Fourth Quarter 2016 Total Revenue $ - $ - $ - $ - Operating expenses $ 822 $ 1,040 $ 1,670 $ 7,831 Other income/(expense) $ (81) $ (93) $ (200) $ (917) Net loss $ (903) $ (1,133) $ (1,870) $ (8,748) Basic and diluted net loss per common share $ (0.09) $ (0.11) $ (0.19) $ (0.64) 2015 Total Revenue $ - $ - $ - $ - Operating expenses $ 2,260 $ 537 $ 658 $ 843 Other income/(expense) $ - $ (42) $ (58) $ (68) Net loss $ (2,260) $ (579) $ (716) $ (911) Basic and diluted net loss per common share $ (0.23) $ (0.06) $ (0.07) $ (0.09)

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2016
Subsequent Events [Abstract]
Subsequent Events [Text Block]	Note 11 – Subsequent Events Private Placement Financing On January 31, 2017, the Company closed the final round of financing totaling gross proceeds of $ 55.5 5.5 10 10,000 2,500 8.50 65,000 five 8,536,774 2,134,193 853,667 10 COH Issuance of Shares In February 2017, the Company issued 293,588 5.73 1.7 City of Hope Agreements On February 17, 2017, the Company and COH amended and restated the Original Agreement in connection with the covered patents by entering into three separate amended and restated exclusive license agreements, one relating to CD123, one relating to IL-13 and one relating to the spacer technology, that amended the Original Agreement in certain other respects, and collectively replace the Original Agreement in its entirety. The total potential consideration payable to COH by the Company, in equity or cash, did not, in the aggregate, change materially from the Original Agreement. A&R CD123 License On February 17, 2017, the Company entered into an Amended and Restated Exclusive License Agreement with COH to acquire intellectual property rights pertaining to CD123 patent rights (the “A&R CD123 License”). Pursuant to the A&R CD123 License, the Company and COH acknowledge that an upfront fee has already been paid under the Original Agreement. In addition, an annual maintenance fee will continue to apply. COH is eligible to receive milestone payments totaling approximately $ 14.5 A&R IL-13 License On February 17, 2017, the Company entered into an Amended and Restated Exclusive License Agreement with COH to acquire intellectual property rights pertaining to IL-13 patent rights (the “A&R IL-13 License”). Pursuant to the A&R IL-13 License, the Company and COH acknowledge that an upfront fee has already been paid under the Original Agreement. In addition, an annual maintenance fee will continue to apply. COH is eligible to receive milestone payments totaling approximately $ 14.5 A&R Spacer License On February 17, 2017, the Company entered into an Amended and Restated Exclusive License Agreement with COH to acquire intellectual property rights pertaining to Spacer patent rights (the “A&R Spacer License”). Pursuant to the A&R Spacer License, the Company and COH acknowledged that an upfront fee has already been paid under the Original Agreement. In addition, an annual maintenance fee will continue to apply. No royalties are due if the Spacer technology is used in conjunction with a CD123 CAR or an IL-13 CAR, and royalty payments in the low single digits are due on net sales of licensed products if the Spacer technology is used in conjunction with other intellectual property. The Company is obligated to pay COH a percentage of certain revenues received in connection with a sublicense in the mid-thirties. In addition, equity grants made under the Original Agreement were acknowledged, and the anti-dilution provisions of the Original Agreement were carried forward. IV/ICV Agreement On February 17, 2017, the Company entered into an exclusive license agreement (the “IV/ICV Agreement”) with COH to acquire intellectual property rights in patent applications related to the intraventricular and intracerebroventricular methods of delivering T cells that express CARs. Pursuant to the IV/ICV Agreement, the Company will pay COH an upfront fee of $ 125,000 125,000 License with University of California On March 17, 2017 the Company entered into an exclusive license agreement with the Regents of the University of California (“UCLA License”) to acquire intellectual property rights in patent applications related to the engineered anti-prostatestem cell antigen antibodies for cancer targeting and detection. Pursuant to the Agreement, the Company will pay UCLA an upfront fee of $ 200,000 Related Party Transactions Advisory Agreement with Caribe BioAdvisors, LLC As of December 30, 2016, the Board of the Company by unanimous written consent, approved and authorized the execution of an advisory agreement dated January 1, 2017 (the “Advisory Agreement”) with Caribe BioAdvisors, LLC (the “Advisor”), owned by Michael S. Weiss (“Mr. Weiss”), the Chairman of the Board, to provide the board advisory services of Mr. Weiss as Chairman of the Board. Pursuant to the Advisory Agreement, the Advisor will be paid an annual cash fee of $ 60,000 Issuance to Shares to Fortress On March 13, 2017, the Company issued to Fortress 767,264 5.73

Significant Accounting Polici19

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation The Company’s financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The Company has no subsidiaries. The financial statements may not be indicative of future performance and may not reflect what the Company’s results of operations, financial position, and cash flows would have been had Mustang operated as an independent entity. Certain estimates have been made to provide financial statements for stand-alone reporting purposes. All inter-company transactions between Fortress and Mustang are classified as due to related party in the financial statements. The Company believes that the assumptions underlying the financial statements are reasonable.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. There were no cash equivalents at December 31, 2016 and 2015.
Research and Development Expense, Policy [Policy Text Block]	Research and Development Costs Research and development costs are expensed as incurred. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. Upfront and milestone payments due to third parties that perform research and development services on the Company’s behalf will be expensed as services are rendered or when the milestone is achieved. Research and development costs primarily consist of personnel related expenses, including salaries, benefits, travel, and other related expenses, stock-based compensation, payments made to third parties for license and milestone costs related to in-licensed products and technology, payments made to third party contract research organizations for preclinical and clinical studies, investigative sites for clinical trials, consultants, the cost of acquiring and manufacturing clinical trial materials, costs associated with regulatory filings, laboratory costs and other supplies. Costs incurred in obtaining technology licenses are charged to research and development expense if the technology licensed has not reached commercial feasibility and has no alternative future use. The licenses purchased by the Company require substantial completion of research and development, regulatory and marketing approval efforts in order to reach commercial feasibility and has no alternative future use. Accordingly, the total purchase price for the licenses acquired is reflected as research and development – licenses acquired on the Company’s Statements of Operations.
Annual Equity Fee [Policy Text Block]	Annual Equity Fee Prior to the July 2016 amendment to the Founder’s Agreement, Fortress was entitled to an annual fee on each anniversary date equal to 2.5 The Company recorded the Annual Equity Fee in connection with the Founders Agreement with Mustang as contingent consideration. Contingent consideration is recorded when probable and reasonably estimable. The Company’s future share prices cannot be estimated due to the nature of its assets and the Company’s stage of development. Due to these uncertainties, the Company concluded that it could not reasonably estimate the contingent consideration until shares were actually issued on March 13, 2016. Because the issuance of shares on March 13, 2016 occurred prior to the issuance of the December 31, 2015 financial statements, the Company recorded approximately $ 190,000
Annual Stock Dividend [Policy Text Block]	Annual Stock Dividend In July 2016, in connection with the Amended and Restated Articles of Incorporation, the Company issued 250,000 2.5 The Company recorded the Annual Stock Dividend due Fortress as contingent consideration. Contingent consideration is recorded when probable and reasonably estimable. The Company’s future share prices cannot be estimated due to the nature of its assets and the Company’s stage of development. Due to these uncertainties, the Company concluded that it could not reasonably estimate the contingent consideration until shares were actually issued on March 13, 2017. Because the issuance of shares on March 13, 2017 occurred prior to the issuance of the December 31, 2016 financial statements, the Company recorded approximately $ 4.4
Fair Value Measurement, Policy [Policy Text Block]	Fair Value Measurement The Company follows accounting guidance on fair value measurements for financial assets and liabilities measured at fair value on a recurring basis. Under the accounting guidance, fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. The accounting guidance requires fair value measurements be classified and disclosed in one of the following three categories: Level 1: Quoted prices in active markets for identical assets or liabilities. Level 2: Observable inputs other than Level 1 prices, for similar assets or liabilities that are directly or indirectly observable in the marketplace. Level 3: Unobservable inputs which are supported by little or no market activity and that are financial instruments whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability.
Valuation Of Warrant Related To NSC Note [Policy Text Block]	Valuation of Warrant Related to NSC Note In accordance with ASC 815, the Company classified the fair value of the warrant (“Contingently Issuable Warrants”) that may have been granted in connection with the NSC Note transferred to the Company in various tranches from July 5, 2016 to October 25, 2016 as a derivative liability as there was a potential that the Company would not have a sufficient number of authorized common shares available to settle this instrument. The Company valued these Contingently Issuable Warrants using an option pricing model (which approximates intrinsic value) with estimates for an expected dividend yield, a risk-free interest rate, and expected volatility together with management’s estimate of the probability of issuance of the Contingently Issuable Warrants. At each reporting period, as long as the Contingently Issuable Warrants were potentially issuable and there was a potential for an insufficient number of authorized shares available to settle the Contingently Issuable Warrants, the Contingently Issuable Warrants should be revalued and any difference from the previous valuation date would be recognized as a change in fair value in the Company’s Statement of Operations.
Reclassified Equity Contracts [Policy Text Block]	Reclassified Equity Contracts The Company accounts for potential shares that can be converted to common stock and if converted, will be in excess of authorized shares, as a liability that is recorded on the balance sheet (at fair value) only until the authorized number of shares is increased (at which time the whole liability will be re-measured, with changes in value included in other income/(expense), and then reclassified to additional paid-in capital). The value of the liability was computed by valuing the securities that management believed were most likely to be converted. This liability is revalued at each reporting date with any change in value included in other income / (expense) until such time as enough shares are authorized to cover all potentially convertible instruments
Income Tax, Policy [Policy Text Block]	Income Taxes For purposes of these financial statements, the Company’s income tax expense and deferred tax balances have been recorded as if it filed tax returns on a stand-alone basis separate from Fortress. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities measured at the enacted tax rates in effect for the year in which these items are expected to reverse. Deferred tax assets are reduced by valuation allowances if, based on the consideration of all available evidence, it is more likely than not that some portion or all of the deferred tax asset will not be realized.
Earnings Per Share, Policy [Policy Text Block]	Net Loss per Share Net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period. Since dividends are declared, paid and set aside among the holders of shares of common stock and Class A Common Stock pro-rata on an as-if-converted basis, the two-class method of computing net loss per share is not required. Diluted net loss per share does not reflect the effect of shares of common stock to be issued upon the exercise of warrants or outstanding Class A preferred shares, as their inclusion would be anti-dilutive. There are 2,243,664 250,000
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	Stock-Based Compensation Expenses The Company expenses stock-based compensation to employees over the requisite service period based on the estimated grant-date fair value of the awards and forfeiture rates. For stock-based compensation awards to non-employees, the Company re-measures the fair value of the non-employee awards at each reporting period prior to vesting and finally at the vesting date of the award. Changes in the estimated fair value of these non-employee awards are recognized as stock-based compensation expense in the period of change.
New Accounting Pronouncements, Policy [Policy Text Block]	In January 2017, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2017-04, Intangibles - Goodwill and Other In January 2017, FASB issued ASU 2017-01, “ Business Combinations (Topic 805) Clarifying the Definition of a Business In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments In April 2016, the FASB issued ASU 2016-10, Revenue from Contracts with Customer (“ASU 2016-10”) In March 2016, the FASB issued ASU 2016-09 Compensation-Stock Compensation (Topic 718), Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”) In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) Leases (Topic 840) In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements-Going Concern

Notes Payable (Tables)

Notes Payable (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule of Debt [Table Text Block]	The following table summarizes NSC Note activities for the year ended December 31, 2016 ($ in thousands). NSC Note Payable Discount NSC Note Payable, Net January 1, 2016 balance $ - $ - $ - Proceeds from issuance of NSC Note 3,600 (129) 3,471 Issuance of warrants in conjunction with NSC debt - (634) (634) Amortization of debt discount - 192 192 Payoff of note (3,600) 571 (3,029) December 31, 2016 balance $ - $ - $ -

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The following table sets forth the changes in the estimated fair value for our Level 3 classified derivative contingently issuable warrant liability ($ in thousands): Contingently Issuable Warrants Fair value, January 1, 2016 $ - Warrant liability associated with NCS debt 634 Change in fair value 159 Issuance of 138,462 warrants with a par value strike price (793) Fair value, December 31, 2016 $ -
Equity Contracts [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The following table represents the activity for the Company's liability for common shares issuable for the year ended December 31, 2016 ($ in thousands): Year Ended December 31, 2016 Beginning Balance $ - Liabilities reclassified 1,682 Change in value of liabilities reclassified - Liabilities reclassified to equity - Ending Balance $ 1,682

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit) (Tables)	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Note [Abstract]
Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block]	A summary of warrant activities for year ended December 31, 2016 is presented below: Weighted Average Weighted Average Remaining Contractual Warrants Exercise Price Life (in years) Outstanding as of January 1, 2016 - $ - - Granted 2,243,664 7.98 - Outstanding as of December 31, 2016 2,243,664 $ 7.98 5.16

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	A reconciliation of the statutory U.S. federal rate to the Company’s effective tax rate is as follows: For the years ended December 31, 2016 2015 Statutory federal income tax rate 35 % 35 % State taxes, net of federal tax benefit 13 % 5 % Non-deductible items (3) % (2) % Credits - 1 % Rate change 1 % - Other 1 % - Change in valuation allowance (47) % (39) % Income taxes provision (benefit) - -
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	The components of the net deferred tax asset as of December 31, 2016 and 2015 are the following ($ in thousands): As of December 31, 2016 2015 Deferred tax assets: Net operating loss carryovers $ 3,310 $ 893 Stock compensation and other 301 - Change in warrant liability 76 - Amortization of license 3,848 815 Start up costs 13 - Tax credits 89 38 Total deferred tax assets 7,637 1,746 Less valuation allowance (7,637) (1,746) Deferred tax assets, net of valuation allowance $ - $ -

Quarterly Financial Date (una24

Quarterly Financial Date (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Data [Abstract]
Quarterly Financial Information [Table Text Block]	(in thousands, except per share data) First Quarter Second Quarter Third Quarter Fourth Quarter 2016 Total Revenue $ - $ - $ - $ - Operating expenses $ 822 $ 1,040 $ 1,670 $ 7,831 Other income/(expense) $ (81) $ (93) $ (200) $ (917) Net loss $ (903) $ (1,133) $ (1,870) $ (8,748) Basic and diluted net loss per common share $ (0.09) $ (0.11) $ (0.19) $ (0.64) 2015 Total Revenue $ - $ - $ - $ - Operating expenses $ 2,260 $ 537 $ 658 $ 843 Other income/(expense) $ - $ (42) $ (58) $ (68) Net loss $ (2,260) $ (579) $ (716) $ (911) Basic and diluted net loss per common share $ (0.23) $ (0.06) $ (0.07) $ (0.09)

Significant Accounting Polici25

Significant Accounting Policies (Details Textual) - USD ($)	1 Months Ended	10 Months Ended	12 Months Ended
	Jul. 31, 2016	Dec. 31, 2015	Dec. 31, 2016
Research and Development Asset Acquired Other than Through Business Combination, Fair Value Acquired			$ 4,400,000
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			2,243,664
Fortress Biotech, Inc [Member]
Annual Fee On Diluted Outstanding Equity, Percentage			2.50%
Research and Development Asset Acquired Other than Through Business Combination, Fair Value Acquired		$ 190,000	$ 4,400,000
Fortress Biotech, Inc [Member] | Common Stock [Member]
Stock Issued During Period, Shares, Issued for Services		250,000
Series A Preferred Stock [Member]
Stock Issued During Period, Shares, Issued for Services		0	0
Series A Preferred Stock [Member] | Preferred Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			250,000
Series A Preferred Stock [Member] | Fortress Biotech, Inc [Member]
Stock Issued During Period, Shares, Issued for Services	250,000
Preferred Stock, Dividend Rate, Percentage	2.50%

COH Agreements (Details Textual

COH Agreements (Details Textual) - USD ($)	1 Months Ended		10 Months Ended	12 Months Ended
	Feb. 28, 2017	Mar. 17, 2015	Dec. 31, 2015	Dec. 31, 2016	Mar. 13, 2017	Dec. 30, 2015
Research and Development Expense			$ 1,500,000	$ 2,000,000
Stock Issued During Period, Value, Issued for Services			$ 147,000	$ 862,000
Common Stock, Shares Subscribed but Unissued			250,000	767,264
Research and Development Asset Acquired Other than Through Business Combination, Fair Value Acquired				$ 4,400,000
Common Stock, Shares, Outstanding			2,000,000	15,165,244
Stephen Forman [Member]
Annual Consulting Fees				$ 60,000
Christine Brown [Member]
Annual Consulting Fees				60,000
Fortress Biotech, Inc [Member]
Research and Development Asset Acquired Other than Through Business Combination, Fair Value Acquired			$ 190,000	$ 4,400,000
Fortress Biotech, Inc [Member] | Common Stock [Member]
Shares Issued, Price Per Share			$ 0.147
Stock Issued During Period, Value, Issued for Services			$ 36,750
Common Stock, Shares Subscribed but Unissued				2,000,000
Fortress Biotech, Inc [Member] | Subsequent Event [Member]
Shares Issued, Price Per Share					$ 5.73
City Of Hope [Member]
Payment Of Upfront Fees		$ 2,000,000
Stock Issued During Period, Shares, Other		1,000,000
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		10.00%
Marketability Percentage Of Invested Capital		44.80%
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent		30.00%
Share Price		$ 0.147
Stock Issued During Period, Value, Other		$ 147,000
Research And Development Expense, Sponsored Research Payment		$ 2,000,000
City Of Hope [Member] | Subsequent Event [Member]
Stock Issued During Period, Shares, Purchase of Assets	293,588
Shares Issued, Price Per Share	$ 5.73
Proceeds from Issuance of Common Stock	$ 1,700,000
Fair Value Assumptions, Expected Volatility Rate	77.00%
Fair Value Assumptions, Risk Free Interest Rate	1.93%
Third Party Investors [Member] | Subsequent Event [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	10.00%
Proceeds from Issuance of Common Stock	$ 10,000,000
Preferred Class A [Member] | Fortress Biotech, Inc [Member]
Share Price				$ 5.73
Common Stock, Shares Subscribed but Unissued				767,264
Common Class A [Member]
Stock Issued During Period, Value, Issued for Services			$ 0	$ 0
Common Stock, Shares, Outstanding			1,000,000	1,000,000
Noncontrolling Interest, Ownership Percentage by Parent				6.10%		10.00%

Related Party Agreements (Detai

Related Party Agreements (Details Textual) - USD ($)	Apr. 08, 2016	Mar. 13, 2016	Sep. 30, 2016	Jul. 31, 2016	May 17, 2016	Dec. 31, 2015	Dec. 31, 2016
Proceeds from Related Party Debt						$ 3,571,000	$ 2,221,000
Founders Agreement Term					15 years
Additional Consideration Under Founders Agreement Description					(i) pay an equity fee in shares of common stock, payable within five (5) business days of the closing of any equity or debt financing for Mustang or any of its respective subsidiaries that occurs after the effective date of the Mustang Founders Agreement and ending on the date when Fortress no longer has majority voting control in the Companys voting equity, equal to two and one-half (2.5%) of the gross amount of any such equity or debt financing; and (ii) pay a cash fee equal to four and one-half percent (4.5%) of the Companys annual net sales, payable on an annual basis, within ninety (90) days of the end of each calendar year. In the event of a Change in Control, the Company will pay a one-time change in control fee equal to five (5x) times the product of (A) net sales for the twelve (12) months immediately preceding the change in control and (B) four and one-half percent (4.5%).
Fortress Biotech, Inc [Member]
Proceeds from Related Party Debt					$ 2,000,000
Noncontrolling Interest, Ownership Percentage by Parent		2.50%
Annual Consulting Fees		$ 500,000
Increase In Annual Consulting Fees		1,000,000
Excess In Net Assets Value		$ 100,000,000
Annual Fees Expenses On Founders Agreement						$ 375,000	500,000
Chord Advisors, LLC [Member]
Back Office Accounting Functions Expenses	$ 5,000
Accounting Analysis And Financial Reporting Fees	$ 7,500
Professional Fees							$ 48,000
National Holdings, Inc. [Member]
Business Acquisition, Percentage of Voting Interests Acquired			56.60%
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures			$ 3,600,000
Notes Issued, Placement Fees Percentage			10.00%
Percentage Of Placement Agent Fees Payable			10.00%
Percentage Of Warrants Issuable On Offering Price			25.00%
Payments for Other Fees			$ 3,600,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			601,486
Common Class B [Member]
Conversion of Stock, Shares Converted				7,250,000
Stock Issued During Period, Shares, Issued for Services						0	250,000,000
Common Class B [Member] | Fortress Biotech, Inc [Member]
Stock Issued During Period, Shares, Issued for Services		250,000
Series A Preferred Stock [Member]
Conversion of Stock, Shares Issued							250,000
Preferred Stock, Voting Rights					Each share of Class A Preferred Stock is convertible, at Fortress option, into one fully paid and nonassessable share of Mustang common stock, subject to certain adjustments. As holders of Class A Preferred Stock, Fortress will receive on each March 13 (each a PIK Dividend Payment Date) until the date all outstanding Class A Preferred Stock is converted into common stock or redeemed (and the purchase price is paid in full), pro rata per share dividends paid in additional fully paid and nonassessable shares of common stock (PIK Dividends) such that the aggregate number of shares of common stock issued pursuant to such PIK Dividend is equal to two and one-half percent (2.5%) of Mustangs fully-diluted outstanding capitalization on the date that is one (1) business day prior to any PIK Dividend Payment Date.
Stock Issued During Period, Shares, Issued for Services						0	0
Convertible Common Stock [Member]
Conversion of Stock, Shares Issued							7,000,000

Notes Payable (Details)

Notes Payable (Details) - USD ($) $ in Thousands	10 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016
Debt Instrument [Line Items]
Proceeds From Notes Payable, Gross	$ 0	$ (3,600)
Amortization of debt discount	0	763
NSC Note Payable Net, Amortization of debt discount	0	763
NSC Note [Member]
Debt Instrument [Line Items]
NSC Note Payable, beginning balance		0
Proceeds From Notes Payable, Gross		3,600
NSC Note Payable, Payoff of note		(3,600)
NSC Note Payable, ending balance	0	0
Discount, beginning balance		0
Proceeds from issuance of NSC Note		(129)
Issuance of warrants in conjunction with NSC debt		(634)
Amortization of debt discount		192
Discount, Payoff of note		571
Discount, ending balance	0	0
NSC Note Payable Net , beginning balance		0
Proceeds from issuance of NSC Note		3,471
NSC Note Payable Net, Issuance of warrants in conjunction with NSC debt		(634)
NSC Note Payable Net, Amortization of debt discount		192
NSC Note Payable Net, Repayments of Notes Payable		(3,029)
NSC Note Payable Net, ending balance	$ 0	$ 0

Notes Payable (Details Textual)

Notes Payable (Details Textual) - USD ($)	Mar. 02, 2015	Oct. 25, 2016	Jul. 05, 2016	Jul. 29, 2015	Dec. 31, 2015	Dec. 31, 2016
Debt Instrument [Line Items]
Percentage Of Warrants Issued On Outstanding Note Amount				25.00%
Class of Warrants Or Rights Issued, Warrants Term				10 years
Notes Payable, Related Parties, Current					$ 3,571,000	$ 320,000
Interest Expense, Debt					0	895,000
Amortization of Debt Discount (Premium)					0	$ 763,000
Working Capital Promissory Note [Member] | Fortress Biotech, Inc [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						8.00%
Notes Payable, Related Parties, Current						$ 320,000
Interest Expense, Debt					$ 168,000	$ 253,000
National Securities Corporation Note [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						8.00%
Interest Expense, Debt						$ 140,000
Percentage Of Contingently Issuable Warrants On Indebtedness Transferred			25.00%
Debt Instrument, Face Amount		$ 3,600,000	$ 3,600,000
Debt Related Commitment Fees and Debt Issuance Costs			$ 129,000
Amortization of Debt Discount (Premium)						$ 763,000
Debt Instrument, Interest Rate, Effective Percentage			23.10%
Debt Instrument, Unamortized Discount			$ 634,000
Issuance Of Warrants, In Conjunction With Notes Payable		$ 138,462
National Securities Corporation Note [Member] | Fortress Biotech, Inc [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Debt	$ 10,000,000

Fair Value Measurement (Details

Fair Value Measurement (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)shares
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Class Of Warrant Or Right, Warrants Issued | shares	138,462
Warrant [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Beginning balance	$ 0
Warrant liability associated with NCS debt	634
Change in fair value	159
Issuance of 138,462 warrants with a par value strike price	(793)
Fair value, Ending balance	$ 0
Class Of Warrant Or Right, Warrants Issued | shares	138,462

Fair Value Measurement (Detai31

Fair Value Measurement (Details 2) - Equity Contracts [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Beginning balance	$ 0
Liabilities reclassified	1,682
Change in value of liabilities reclassified	0
Liabilities reclassified to equity	0
Fair value, Ending balance	$ 1,682

Fair Value Measurement (Detai32

Fair Value Measurement (Details Textual)	12 Months Ended
	Dec. 31, 2016shares
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights, Description	If the Company has an initial public offering and raises sufficient equity capital so that it has cash equal to five times the amount of the portion of the proceeds of the NSC Note transferred to it, then NSC will receive a warrant to purchase the Companys stock equal to 25% of the outstanding note divided by the lowest price the Company sells its equity in its first third party financing.
Class Of Warrant Or Right, Warrants Issued	138,462
Class Of Warrant Or Right, Warrants Term	ten year term

Commitments and Contingencies (

Commitments and Contingencies (Details Textual)	Jan. 15, 2016
City Of Hope [Member]
Loss Contingencies [Line Items]
Failed Contingency Damages Awarded Percentage	15.00%

Stockholders' Equity (Deficit34

Stockholders' Equity (Deficit) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants, Outstanding Beginning of year	0
Warrants, Granted	2,243,664
Warrants, Outstanding End of year	2,243,664	0
Weighted Average Exercise Price, Outstanding Beginning of year	$ 0
Weighted Average Exercise Price, Granted	7.98
Weighted Average Exercise Price, Outstanding End of year	$ 7.98	$ 0
Weighted Average Remaining Contractual Life, Outstanding Beginning of year	5 years 1 month 28 days	0 years
Weighted Average Remaining Contractual Life, Granted	0 years
Weighted Average Remaining Contractual Life, Outstanding End of year	5 years 1 month 28 days	0 years

Stockholders' Equity (Deficit35

Stockholders' Equity (Deficit) (Details Textual) - USD ($)	Dec. 12, 2016	Mar. 13, 2016	Dec. 29, 2016	Nov. 30, 2016	Oct. 25, 2016	Sep. 30, 2016	Jul. 27, 2016	Mar. 17, 2015	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Jul. 31, 2016	Jul. 26, 2016	Mar. 12, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares, Issued									2,000,000	15,165,244	2,000,000
Common Stock, Shares Authorized									50,000,000	50,000,000	50,000,000	50,000,000	2,000,000
Common Stock, Par or Stated Value Per Share									$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Common Stock, Voting Rights										1.1
Proceeds from Issuance or Sale of Equity									$ 0	$ 35,008,000
Payments for Underwriting Expense										$ 1,400,000
Common Stock, Shares Subscribed but Unissued									250,000	767,264	250,000
Common Stock, Value, Subscriptions									$ 190,000	$ 4,396,000	$ 190,000
Shares, Outstanding
Class Of Warrant Or Right, Warrants Term										ten year term
Class Of Warrant Or Right, Warrants Issued										138,462
Stock Issued During Period, Value, New Issues										$ 39,098,000
Payments of Stock Issuance Costs										$ 4,090,000	$ 0
Capital Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Placement Agent Fee	10.00%		10.00%	10.00%	10.00%
Stock Issued During Period, Shares, New Issues	477,000		632,246	1,900,215	1,090,580
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 8.50		$ 8.50	$ 8.50	$ 8.50
Shares Issued, Price Per Share	$ 65,000		$ 65,000	$ 65,000	$ 65,000
Class Of Warrant Or Right, Warrants Term	five-year term		five-year term	five-year term	Class Of Warrant Or Right, Warrants Term
Class Of Warrant Or Right, Warrants Issued	119,250		158,062	475,053	272,645
Stock Issued During Period, Value, New Issues	$ 3,100,000		$ 4,100,000	$ 12,400,000
Payments of Stock Issuance Costs	$ 310,000		$ 410,000	$ 1,200,000	$ 109,058
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right	2,500		2,500	2,500	2,500
Warrant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues						478,708
Class Of Warrant Or Right, Warrants Issued										138,462
Warrant [Member] | Capital Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues					10,000
Payments of Stock Issuance Costs	$ 47,700		$ 63,224	$ 190,021
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense										$ 862,000
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues						1,914,833	7,000,000
Common Stock [Member] | Capital Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues	10,000		10,000	10,000
Series A Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized													250,000
Stock Issued During Period, Shares, New Issues							250,000			0
Shares, Outstanding									0	250,000,000	0
Stock Issued During Period, Value, New Issues										$ 0
Common Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares, Issued									7,000,000	0	7,000,000
Common Stock, Shares Authorized												15,000,000
Stock Issued During Period, Shares, New Issues										0
Shares, Outstanding									7,000,000,000	0	7,000,000,000
Stock Repurchased and Retired During Period, Shares							7,200,000
Stock Issued During Period, Value, New Issues										$ 0
Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares, Issued									1,000,000	1,000,000	1,000,000
Common Stock, Shares Authorized												1,000,000
Stock Issued During Period, Shares, New Issues										0
Shares, Outstanding									1,000,000,000	1,000,000,000	1,000,000,000
Stock Issued During Period, Value, New Issues										$ 0
Fortress Biotech, Inc [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Of Common Stock, Percentage										2.50%
Common Stock, Value, Subscriptions										$ 900
Fortress Biotech, Inc [Member] | Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues										150,370
Common Stock, Shares Subscribed but Unissued										2,000,000
Shares Issued, Price Per Share									$ 0.147		$ 0.147
Fortress Biotech, Inc [Member] | Common Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares, Issued		250,000
Common Stock, Shares Subscribed but Unissued										7,000,000
Diluted Outstanding Equity, Percentage		2.50%
City of Hope National Medical Center [Member] | License Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues										1,000,000
Payment Of Upfront Fees								$ 2,000,000
City of Hope National Medical Center [Member] | Common Class A [Member] | License Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners										10.00%
Shares, Outstanding										1,000,000
National Securities, Inc [Member] | Capital Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments of Stock Issuance Costs					$ 710,000
Private Placement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant Purchase Price Per Unit						$ 65,000
Warrants Issued						191,483
Stock Issued During Period, Shares, New Issues						10,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights						2,500
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 8.50
Proceeds from Issuance or Sale of Equity										$ 12,400,000
Payments for Underwriting Expense										$ 1,300,000
Private Placement [Member] | Capital Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Value, New Issues					$ 7,100,000
Private Placement [Member] | National Holdings Corporation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Placement Agent Fee						10.00%
Percentage Of Shares Issued To Placement Agent						10.00%

Income Taxes (Details)

Income Taxes (Details)	10 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016
Statutory federal income tax rate	35.00%	35.00%
State taxes, net of federal tax benefit	5.00%	13.00%
Non-deductible items	(2.00%)	(3.00%)
Credits	1.00%	0.00%
Rate change	0.00%	1.00%
Other	0.00%	1.00%
Change in valuation allowance	(39.00%)	(47.00%)
Income taxes provision (benefit)	0.00%	0.00%

Income Taxes (Details 1)

Income Taxes (Details 1) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Net operating loss carryovers	$ 3,310	$ 893
Stock compensation and other	301	0
Change in warrant liability	76	0
Amortization of license	3,848	815
Start up costs	13	0
Tax credits	89	38
Total deferred tax assets	7,637	1,746
Less valuation allowance	(7,637)	(1,746)
Deferred tax assets, net of valuation allowance	$ 0	$ 0

Income Taxes (Details Textual)

Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Assets, Valuation Allowance	$ 7,637	$ 1,746
Domestic Tax Authority [Member]
Operating Loss Carryforwards	$ 7,300
Operating Loss Carryforward Expire Period	2035 years
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	$ 13,500
Operating Loss Carryforward Expire Period	2025 years

Quarterly Financial Date (una39

Quarterly Financial Date (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended							10 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2016
Total Revenue	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Operating expenses	2,260	7,831	1,670	1,040	822	843	658	537	$ 4,298	$ 11,363
Other income/(expense)	0	(917)	(200)	(93)	(81)	(68)	(58)	(42)	(168)	(1,291)
Net loss	$ (2,260)	$ (8,748)	$ (1,870)	$ (1,133)	$ (903)	$ (911)	$ (716)	$ (579)	$ (4,466)	$ (12,654)
Basic and diluted net loss per common share	$ (0.23)	$ (0.64)	$ (0.19)	$ (0.11)	$ (0.09)	$ (0.09)	$ (0.07)	$ (0.06)	$ (0.45)	$ (1.15)

Subsequent Events (Details Text

Subsequent Events (Details Textual) - USD ($)	Mar. 13, 2017	Mar. 17, 2017	Feb. 28, 2017	Feb. 17, 2017	Jan. 31, 2017	Jan. 02, 2017	Sep. 30, 2016	Mar. 17, 2015	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Subsequent Event [Line Items]
Payments of Stock Issuance Costs										$ 4,090,000	$ 0
Stock Issued During Period, Value, Issued for Services									$ 147,000	$ 862,000
City Of Hope [Member]
Subsequent Event [Line Items]
Share Price								$ 0.147
Payment Of Upfront Fees								$ 2,000,000
Private Placement [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues							10,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights							2,500
Class of Warrant or Right, Exercise Price of Warrants or Rights							$ 8.50
Warrant Purchase Price Per Unit							$ 65,000
Warrants Issued							191,483
National Holdings Corporation [Member] | Private Placement [Member]
Subsequent Event [Line Items]
Percentage Of Placement Agent Fee							10.00%
Percentage Of Shares Issued To Placement Agent							10.00%
Subsequent Event [Member]
Subsequent Event [Line Items]
Warrants Issued					2,134,193
Subsequent Event [Member] | City Of Hope [Member]
Subsequent Event [Line Items]
Revenue Recognition Milestone Method Payments Due				$ 125,000
Payments for Other Fees				125,000
Shares Issued, Price Per Share			$ 5.73
Subsequent Event [Member] | City Of Hope [Member] | Licensing Agreements [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, Issued for Services			293,588
Share Price			$ 5.73
Stock Issued During Period, Value, Issued for Services			$ 1,700,000
Subsequent Event [Member] | City Of Hope [Member] | A&R CD123 License [Member]
Subsequent Event [Line Items]
Revenue Recognition Milestone Method Payments Due				14,500,000
Subsequent Event [Member] | City Of Hope [Member] | A&R IL-13 License [Member]
Subsequent Event [Line Items]
Revenue Recognition Milestone Method Payments Due				$ 14,500,000
Subsequent Event [Member] | Unregistered Common Stock [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues					8,536,774
Subsequent Event [Member] | Private Placement [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues					10,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights					2,500
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 8.50
Warrant Purchase Price Per Unit					$ 65,000
Warrant Expiration Term					5 years
Subsequent Event [Member] | National Holdings Corporation [Member] | Private Placement [Member]
Subsequent Event [Line Items]
Proceeds from Issuance of Private Placement					$ 55,500,000
Payments of Stock Issuance Costs					$ 5,500,000
Percentage Of Placement Agent Fee					10.00%
Warrants Issued					853,667
Percentage Of Shares Issued To Placement Agent					10.00%
Subsequent Event [Member] | University of California [Member] | UCLA License [Member]
Subsequent Event [Line Items]
Payment Of Upfront Fees		$ 200,000
Subsequent Event [Member] | Caribe BioAdvisors, LLC [Member]
Subsequent Event [Line Items]
Payments for Other Fees						$ 60,000
Subsequent Event [Member] | Fortress Biotech, Inc [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, Issued for Services	767,264
Shares Issued, Price Per Share	$ 5.73