Phio Pharmaceuticals (PHIO) 10-K 30 Mar 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Mar. 15, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	RXII
Entity Registrant Name	RXi Pharmaceuticals Corp
Entity Central Index Key	1,533,040
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		65,349,121
Entity Public Float			$ 31,656,117

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 5,117	$ 8,496
Restricted cash	50	50
Short-term investments	5,500
Prepaid expenses	311	442
Total current assets	10,978	8,988
Property and equipment, net of accumulated depreciation of $778 and $702, in 2015 and 2014, respectively	163	183
Other assets	18	18
Total assets	11,159	9,189
Current liabilities:
Accounts payable	1,163	285
Accrued expenses	1,106	1,002
Deferred revenue		47
Total current liabilities	$ 2,269	$ 1,334
Commitments and contingencies (Note 6)
Stockholders' equity:
Preferred stock	$ 0	$ 0
Common stock, $0.0001 par value, 100,000,000 shares authorized; 65,349,121 and 21,984,272 shares issued and outstanding at December 31, 2015 and 2014, respectively	7	2
Additional paid-in capital	65,988	48,047
Accumulated deficit	(57,105)	(46,882)
Total stockholders' equity	8,890	2,745
Total liabilities, convertible preferred stock and stockholders' equity	$ 11,159	9,189
Series A Convertible Preferred Stock [Member]
Convertible preferred stock:
Series A convertible preferred stock, $0.0001 par value, no shares authorized, issued or outstanding at December 31, 2015; 15,000 shares authorized and 5,110 shares issued and outstanding at December 31, 2014 (at liquidation value)		5,110
Series A-1 Convertible Preferred Stock [Member]
Stockholders' equity:
Preferred stock		1,578
Total stockholders' equity		$ 1,578

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accumulated depreciation	$ 778	$ 702
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	65,349,121	21,984,272
Common stock, shares outstanding	65,349,121	21,984,272
Series A Convertible Preferred Stock [Member]
Series A Preferred Stock, par value	$ 0.0001	$ 0.0001
Series A Preferred Stock, shares authorized	0	15,000
Series A Preferred Stock, shares issued	0	5,110
Series A Preferred Stock, shares outstanding	0	5,110
Series A-1 Convertible Preferred Stock [Member]
Series A-1 Preferred Stock, par value	$ 0.0001	$ 0.0001
Series A-1 Preferred Stock, shares authorized	0	10,000
Series A-1 Preferred Stock, shares issued	0	1,578
Series A-1 Preferred Stock, shares outstanding	0	1,578

Statements of Operations

Statements of Operations - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Revenue		$ 34	$ 71
Operating expenses:
Research and development expenses	[1]	6,925	5,680
General and administrative expenses	[1]	3,346	3,217
Total operating expenses		10,271	8,897
Operating loss		(10,237)	(8,826)
Other income:
Interest income, net		16	17
Other income (expense), net		(2)	9
Total other income		14	26
Loss before income taxes		(10,223)	(8,800)
Provision for income taxes		0	0
Net loss		(10,223)	(8,800)
Series A and A-1 convertible preferred stock dividends		(209)	(4,130)
Net loss applicable to common stockholders		$ (10,432)	$ (12,930)
Net loss per common share applicable to common stockholders:
Basic and diluted		$ (0.21)	$ (0.79)
Weighted average common shares: basic and diluted		49,703,822	16,362,905
[1]	Non-cash stock-based compensation expenses included in operating expenses are as follows: Research and development $ 632 $ 836 General and administrative $ 903 $ 1,010

Statements of Operations (Paren

Statements of Operations (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Research and Development Expenses [Member]
Non-cash stock-based compensation expenses	$ 632	$ 836
General and Administrative Expenses [Member]
Non-cash stock-based compensation expenses	$ 903	$ 1,010

Statements of Convertible Prefe

Statements of Convertible Preferred Stock and Stockholders' Equity - USD ($) $ in Thousands	Total	Series A Convertible Preferred Stock [Member]	Series A-1 Convertible Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member]Series A Convertible Preferred Stock [Member]	Common Stock [Member]Series A-1 Convertible Preferred Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2013	$ 4,942		$ 2,054	$ 1			$ 40,969	$ (38,082)
Series A convertible preferred stock, Beginning balance at Dec. 31, 2013		$ 7,920
Beginning balance, shares at Dec. 31, 2013			2,054	11,788,045
Series A convertible preferred stock, Beginning balance, shares at Dec. 31, 2013		7,920
Issuance of common stock under Lincoln Park Capital, LLC purchase agreement	1,886						1,886
Issuance of common stock under Lincoln Park Capital, LLC purchase agreement, shares				700,000
Issuance of common stock under employee stock purchase plan	61						61
Issuance of common stock under employee stock purchase plan, shares				32,515
Stock-based compensation expense	1,846						1,846
Dividends issued on Series A and Series A-1 convertible preferred stock	3,774	$ 356	$ 240				3,534
Dividends issued on Series A and Series A-1 convertible preferred stock, shares		356	240
Fair value of Series A and Series A-1 convertible preferred stock dividends	(4,130)						(4,130)
Exchange of Series A convertible preferred stock into Series A-1 convertible preferred stock	3,000	$ (3,000)	$ 3,000
Exchange of Series A convertible preferred stock into Series A-1 convertible preferred stock, shares		(3,000)	3,000
Conversions of Series A and Series A-1 convertible preferred stock into common stock	166	$ (166)	$ (3,716)	$ 1			3,881
Conversions of Series A and Series A-1 convertible preferred stock into common stock, shares		(166)	(3,716)	9,463,712	405,720	9,057,992
Net loss	(8,800)							(8,800)
Ending balance at Dec. 31, 2014	2,745		$ 1,578	$ 2			48,047	(46,882)
Series A convertible preferred stock, Ending balance at Dec. 31, 2014		$ 5,110
Ending balance, shares at Dec. 31, 2014			1,578	21,984,272
Series A convertible preferred stock, Ending balance, shares at Dec. 31, 2014		5,110
Issuance of common stock under Lincoln Park Capital, LLC purchase agreement	64						64
Issuance of common stock under Lincoln Park Capital, LLC purchase agreement, shares				50,000
Issuance of common stock in exchange for patent and technology rights	228						228
Issuance of common stock in exchange for patent and technology rights, shares				200,000
Issuance of common stock in connection with public offering, net of offering costs of $1,198	9,202			$ 3			9,199
Issuance of common stock in connection with public offering, net of offering costs of $1,198, shares				26,000,000
Issuance of common stock under employee stock purchase plan	31						31
Issuance of common stock under employee stock purchase plan, shares				69,546
Issuance of common stock upon exercise of warrants in connection with public offering	198						198
Issuance of common stock upon exercise of warrants in connection with public offering, shares				435,000
Stock-based compensation expense	1,535						1,535
Dividends issued on Series A and Series A-1 convertible preferred stock	104	$ 105	$ 21				83
Dividends issued on Series A and Series A-1 convertible preferred stock, shares		105	21
Fair value of Series A and Series A-1 convertible preferred stock dividends	209						209
Exchange of Series A convertible preferred stock into Series A-1 convertible preferred stock	2,000	$ (2,000)	$ 2,000
Exchange of Series A convertible preferred stock into Series A-1 convertible preferred stock, shares		(2,000)	2,000
Conversions of Series A and Series A-1 convertible preferred stock into common stock	$ 3,215	$ (3,215)	$ (3,599)	$ 2			6,812
Conversions of Series A and Series A-1 convertible preferred stock into common stock, shares	435,000	(3,215)	(3,599)	16,610,303	7,837,400	8,772,903
Net loss	$ (10,223)							(10,223)
Ending balance at Dec. 31, 2015	$ 8,890			$ 7			$ 65,988	$ (57,105)
Ending balance, shares at Dec. 31, 2015				65,349,121
Series A convertible preferred stock, Ending balance, shares at Dec. 31, 2015		0

Statements of Convertible Pref7

Statements of Convertible Preferred Stock and Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Statement of Stockholders' Equity [Abstract]
Offering costs	$ 1,198	$ 114

Statements of Cash Flows

Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net loss	$ (10,223,000)	$ (8,800,000)
Adjustment to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	77,000	87,000
Gain on disposal of property and equipment		(10,000)
Non-cash share-based compensation expense	1,535,000	1,846,000
Fair value of common stock issued in exchange for patent and technology rights	228,000
Changes in operating assets and liabilities:
Prepaid expenses	131,000	(139,000)
Accounts payable	878,000	122,000
Accrued expenses	104,000	(793,000)
Deferred revenue	(47,000)	(71,000)
Net cash used in operating activities	(7,317,000)	(7,758,000)
Cash flows from investing activities:
Purchase of short-term investments	(8,000,000)	(5,000,000)
Maturities of short-term investments	2,500,000	8,000,000
Cash paid for purchase of property and equipment	(57,000)	(95,000)
Proceeds from disposal of property and equipment		12,000
Net cash (used in) provided by investing activities	(5,557,000)	2,917,000
Cash flows from financing activities:
Net proceeds from the issuance of common stock	9,266,000	1,886,000
Proceeds from the issuance of common stock upon the exercise of warrants	198,000
Proceeds from the issuance of common stock in connection with the employee stock purchase plan	31,000	61,000
Net cash provided by financing activities	9,495,000	1,947,000
Net decrease in cash and cash equivalents	(3,379,000)	(2,894,000)
Cash and cash equivalents at the beginning of period	8,496,000	11,390,000
Cash and cash equivalents at the end of period	5,117,000	8,496,000
Supplemental disclosure of non-cash investing and financing activities:
Exchange of Series A convertible preferred stock into Series A-1 convertible preferred stock	2,000,000	3,000,000
Conversion of Series A and Series A-1 convertible preferred stock into common stock	6,814,000	3,882,000
Fair value of Series A and Series A-1 convertible preferred stock dividends	209,000	4,130,000
Series A and Series A-1 convertible preferred stock dividends	$ 126,000	$ 596,000

Nature of Business

Nature of Business	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	1. Nature of Business RXi Pharmaceuticals Corporation (“ RXi we our Company ®

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“ GAAP Uses of Estimates in Preparation of Financial Statements The preparation of financial statements in accordance 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 revenues and expenses during the reporting period. Actual results could differ materially from these estimates. Cash and Cash Equivalents The Company considers all highly liquid debt instruments with an original maturity of three months or less to be cash equivalents. Cash equivalents consist primarily of amounts invested in certificates of deposit. Restricted Cash Restricted cash consists of certificates of deposit held by financial institutions as collateral for the Company’s corporate credit cards. Short-term Investments Short-term investments consist of certificates of deposit with original maturities ranging from three months to one year. Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and short-term investments. The Company maintains cash balances in several accounts with one bank, which at times are in excess of federally insured limits. The Company has established guidelines related to credit ratings and maturities intended to safeguard principal balances and maintain liquidity. The Company’s investments are maintained in accordance with the Company’s investment policy, which defines allowable investments, specifies credit quality standards and limits the exposure of any single issuer. Fair Value of Financial Instruments The carrying amounts reported in the balance sheet for cash equivalents, restricted cash, short-term investments and accounts payable approximate their fair values due to their short-term nature or market rates of interest. Property and Equipment Property and equipment are stated at cost and depreciated using the straight-line method based on the estimated useful lives of the related assets. The Company provides for depreciation over the assets’ estimated useful lives as follows: Computer equipment 3 years Machinery & equipment 5 years Office furniture 5 years Depreciation and amortization expense for the years ended December 31, 2015 and 2014 was approximately $77,000 and $87,000, respectively. Impairment of Long-Lived Assets The Company reviews long-lived assets for impairment on an interim basis if an event occurs that might reduce the fair value of such assets below their carrying values. An impairment loss would be recognized based on the difference between the carrying value of the asset and its estimated fair value, which would be determined based on either discounted future cash flows or other appropriate fair value methods. The Company believes no impairment existed as of December 31, 2015 and 2014. Revenue Recognition Revenue is recognized when there is persuasive evidence of an arrangement, the fee is fixed or determinable, delivery has occurred or services have been rendered and collection of the related receivable is reasonably assured. The Company may generate revenue from product sales, license agreements, collaborative research and development arrangements and government grants. The Company’s principal source of revenue consists of government research grants. Revenue from a government grant is recognized over the respective contract periods as the services are performed. Payments received prior to the recognition of revenue are recorded as deferred revenue. Research and Development Expenses Research and development costs are charged to expense as incurred and relate to salaries, employee benefits, facility-related expenses, supplies, stock-based compensation related to employees and non-employees involved in the Company’s research and development, external services, other operating costs and overhead related to our research and development departments, costs to acquire technology licenses and expenses associated with preclinical activities and our clinical trials. Payments made by the Company in advance for research and development services not yet provided and/or for materials not yet received are recorded as prepaid expenses. Accrued liabilities are recorded related to those expenses for which vendors have not yet billed us with respect to services provided and/or materials that we have received. Preclinical and clinical trial expenses relate to third-party services, subject-related fees at the sites where our clinical trials are being conducted, laboratory costs, analysis costs, toxicology studies and investigator fees. Costs associated with these expenses are generally payable on the passage of time or when certain milestones are achieved. Expense is recorded during the period incurred or in the period in which a milestone is achieved. In order to ensure that we have adequately provided for preclinical and clinical expenses during the proper period, we maintain an accrual to cover these expenses. These accruals are assessed on a quarterly basis and are based on such assumptions as expected total cost, the number of subjects and clinical trial sites and length of the study. Actual results may differ from these estimates and could have a material impact on our reported results. Our historical accrual estimates have not been materially different from our actual costs. Although the Company believes that its patents and underlying technology have continuing value, the amount of future benefits to be derived from the patents is uncertain. Patent costs are, therefore, expensed as research and development costs as incurred. Stock-based Compensation The Company follows the provisions of the Financial Accounting Standards Board (“ FASB ASC Compensation — Stock Compensation ASC 718 For stock options granted as consideration for services rendered by non-employees, the Company recognizes compensation expense in accordance with the requirements of FASB ASC Topic 505-50, “ Equity Based Payments to Non-Employees Income Taxes The Company recognizes assets or liabilities for the deferred tax consequences of temporary differences between the tax basis of assets or liabilities and their reported amounts in the financial statements in accordance with FASB ASC Topic 740, “Accounting for Income Taxes” ASC 740 . Comprehensive Loss The Company’s comprehensive loss is equal to its net loss for all periods presented. Net loss per Share The Company accounts for and discloses net loss per share attributable to common stockholders in accordance with FASB ASC Topic 260, “ Earnings per Share.”

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2015
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	3. Recent Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ ASU “Revenue from Contracts with Customers (Topic 606) ” In September 2015, the FASB issued ASU 2015-16, “ Simplifying the Accounting for Measurement-Period Adjustments (Topic 805). In November 2015, the FASB issued ASU 2015-17, “ Balance Sheet Classification of Deferred Taxes (Topic 740) ASU 2015-17 In February 2016, the FASB issued ASU 2016-02, “ Leases (Topic 842)

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value Measurements The Company follows the provisions of FASB ASC Topic 820, “ Fair Value Measurements and Disclosures,” 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 Company categorized its restricted cash, cash equivalents and short-term investments as Level 2 hierarchy. The assets classified as Level 2 have initially been valued at the applicable transaction price and subsequently valued, at the end of each reporting period, using other market observable data. Observable market data points include quoted prices, interest rates, reportable trades and other industry and economic events. Financial assets measured at fair value on a recurring basis are summarized as follows, in thousands: Description December 31, 2015 Quoted Prices In Active Markets (Level 1) Other Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 2,500 — 2,500 — Short-term investments 5,500 — 5,500 — Total $ 8,050 $ — $ 8,050 $ — Description December 31, 2014 Quoted Prices In Active Markets (Level 1) Other Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 4,000 — 4,000 — Total $ 4,050 $ — $ 4,050 $ —

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Accrued Expenses	5. Accrued Expenses Accrued expenses consist of the following, in thousands: December 31, 2015 2014 Employee compensation and benefits $ 725 $ 528 Clinical development expenses 225 186 Professional fees 126 165 Research and development costs 20 118 Other 10 5 Total accrued expenses $ 1,106 $ 1,002

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	6. Commitments and Contingencies License Commitments The Company acquires assets under development and enters into research and development arrangements with third parties that often require milestone and royalty payments based on the progress of the asset through development stages. Milestone payments may be required, for example, upon approval of the product for marketing by a regulatory agency. In certain agreements, the Company is required to make royalty payments based upon a percentage of the sales of the products licensed pursuant to such agreements. Because of the contingent nature of these payments, they are not included in the table of contractual obligations shown below (see also Note 12). 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 addition, these arrangements often give the Company the discretion to unilaterally terminate development of the product, which would allow the Company to avoid making the contingent payments; however, the Company is unlikely to cease development if the compound successfully achieves clinical testing objectives. The Company’s contractual license obligations that will require future cash payments as of December 31, 2015 are as follows, in thousands: Year Ending December 31, 2016 $ 200 2017 200 2018 200 2019 165 2020 165 Thereafter 966 Total $ 1,896 Operating Leases The Company leases office and laboratory space for its corporate headquarters and primary research facility in Marlborough, Massachusetts. The lease for the office and lab space will expire in March 2019. Monthly rental expense is approximately $9,500, which includes the Company’s pro rata share of annual real estate taxes and operating expenses. Total rent expense under the Company’s operating leases was $118,000 and $107,500 for the years ended December 31, 2015 and 2014, respectively. At December 31, 2015, the Company’s future minimum payments required under operating leases are as follows, in thousands: Year Ending December 31, 2016 $ 120 2017 117 2018 120 2019 30 Total $ 387 The Company applies the disclosure provisions of FASB ASC Topic 460, “ Guarantor’s Accounting and Disclosure Requirements for Guarantees, Including Indirect Guarantees of Indebtedness of Others ASC 460

Convertible Preferred Stock

Convertible Preferred Stock	12 Months Ended
	Dec. 31, 2015
Text Block [Abstract]
Convertible Preferred Stock	7. Convertible Preferred Stock Dividends On May 22, 2015, the Company entered into an agreement (the “ Acceleration and Conversion Agreement TCP Series A Preferred Stock The Company paid dividends in additional shares of Series A Preferred Stock of 105 and 356 shares for the years ended December 31, 2015 and 2014, respectively. No dividends were paid on the Series A Preferred Stock after May 27, 2015, as all outstanding shares were converted into common stock on this date. Included in the Company’s net loss applicable to common shareholders related to the fair value of the Series A Preferred Stock dividends was $172,000 and $2,399,000 for the years ended December 31, 2015 and 2014, respectively. Conversion During the year ended December 31, 2015, 3,215 shares of Series A Preferred Stock were converted into 7,837,400 shares of common stock. There were no conversions of the Series A Preferred Stock after May 27, 2015, as all outstanding shares were converted into common stock on this date. During the year ended December 31, 2014, 166 shares of Series A Preferred Stock were converted into 405,720 shares of common stock. Elimination On November 6, 2015, the Company filed a Certificate Eliminating the Series A Preferred Stock from the Certificate of Incorporation of the Company with the Secretary of State of the State of Delaware, in order to eliminate from the Charter all matters set forth in the Charter, including the related certificates of designation and increase, relating to the previously issued series of preferred stock of the Company. As a result, the 15,000 shares of unissued Series A Preferred Stock were returned to the status of authorized but unissued shares of preferred stock of the Company, without designation as to series or preferences or rights. As of December 31, 2015, there were no shares of Series A Preferred Stock authorized, outstanding or issued.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	8. Stockholders’ Equity The Company currently has authorized for issuance 100,000,000 shares of common stock, par value $0.0001 per share, and 10,000,000 shares of preferred stock, par value $0.0001 per share. Series A-1 Preferred Stock Dividends On May 22, 2015, the Company entered into the Acceleration and Conversion Agreement with TCP pursuant to which the Company and TCP agreed to accelerate the next dividend payment date from June 30, 2015 to no later than May 29, 2015, and upon payment of such dividend immediately convert the dividend shares into common stock. In connection therewith, the dividend payment date was accelerated to May 27, 2015. There were no shares of Series A-1 convertible preferred stock (“ Series A-1 Preferred Stock The Company paid dividends in additional shares of Series A-1 Preferred Stock of 21 and 240 shares for the years ended December 31, 2015 and 2014, respectively. No dividends were paid on the Series A-1 Preferred Stock after May 27, 2015, as all outstanding shares were converted into common stock on this date. Included in the Company’s net loss applicable to common shareholders related to the fair value of the Series A-1 Preferred Stock dividends was $37,000 and $1,731,000 for the years ended December 31, 2015 and 2014, respectively. Conversion During the year ended December 31, 2015, 3,599 shares of Series A-1 Preferred Stock were converted into 8,772,903 shares of common stock. There were no conversions of the Series A-1 Preferred Stock after May 27, 2015, as all outstanding shares were converted into common stock on this date. During the year ended December 31, 2014, 3,716 shares of Series A-1 Preferred Stock were converted into 9,057,992 shares of common stock. Elimination On November 6, 2015, the Company filed a Certificate Eliminating the Series A-1 Preferred Stock from the Certificate of Incorporation of the Company with the Secretary of State of the State of Delaware, in order to eliminate from the Charter all matters set forth in the Charter, including the related certificates of designation and increase, relating to the previously issued series of preferred stock of the Company. As a result, the 10,000 shares of unissued Series A-1 Preferred Stock were returned to the status of authorized but unissued shares of preferred stock of the Company, without designation as to series or preferences or rights. As of December 31, 2015, there were no shares of Series A-1 Preferred Stock authorized, outstanding or issued. Common Stock Hapten License Agreement On December 17, 2014, the Company entered into an assignment and exclusive license agreement, (the “ Assignment and License Agreement Hapten Lincoln Park Capital Equity Line On April 22, 2014, the Company entered into a purchase agreement (the “ Prior Purchase Agreement LPC On December 18, 2014, the Company entered into a purchase agreement (the “ Purchase Agreement During the year ended December 31, 2015, the Company sold a total of 50,000 shares of common stock to LPC for net proceeds of $64,000 pursuant to and subject to the limitations and conditions set forth in the Purchase Agreement. There have been no other sales made to date under the Purchase Agreement. Per the terms of the public offering (see below), the Company cannot access the equity line until the expiration of the 13-month Overallotment Purchase Rights (defined below). June 2015 Public Offering On June 2, 2015, the Company sold a total of 26,000,000 units at a price of $0.40 per unit in a public offering (the “ Offering Overallotment Purchase Rights Warrants The Company first assessed the Overallotment Purchase Rights and the Warrants under FASB ASC Topic 480, “ Distinguishing Liabilities and Equity ASC 480 Derivatives and Hedging ASC 815 During the year ended December 31, 2015, 435,000 Overallotment Purchase Rights were exercised for gross proceeds of $198,000. Refer to the Series A Preferred Stock and Series A-1 Preferred Stock conversions described above in this Note and Note 7 for shares issued as a result of the conversions of Series A and Series A-1 Preferred Stock during the years ended December 31, 2015 and 2014, respectively.

Net Loss per Share Attributable

Net Loss per Share Attributable to Common Stockholders	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Net Loss per Share Attributable to Common Stockholders	9. Net Loss per Share Attributable to Common Stockholders The following table sets forth the potential common shares excluded from the calculation of net loss per common share attributable to common stockholders because their inclusion would be anti-dilutive: December 31, 2015 2014 Options to purchase common stock 3,323,761 3,000,264 Common stock underlying Series A and Series A-1 convertible preferred stock — 16,300,969 Warrants to purchase common stock 25,569,615 4,615 Total 28,893,376 19,305,848

Stock-based Compensation

Stock-based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation	10. Stock-based Compensation Stock Plans On January 23, 2012, the Company’s Board of Directors and sole stockholder adopted the RXi Pharmaceuticals Corporation 2012 Long-Term Incentive Plan (the “ 2012 Incentive Plan As of December 31, 2015, an aggregate of 5,000,000 shares of common stock were reserved for issuance under the Company’s 2012 Incentive Plan, including 3,323,761 shares subject to outstanding common stock options granted under the 2012 Incentive Plan and 1,674,239 shares available for future grants. Stock options granted by the Company to employees may have different vesting parameters, but generally vest within 48 months after the option grant date and expire within ten years of issuance. Stock-based Compensation The Company uses the Black-Scholes option-pricing model to determine the fair value of all its option grants. For valuing options granted for the years ended December 31, 2015 and 2014, the following assumptions were used: Year Ended December 31, 2015 2014 Risk-free interest rate 1.47 – 2.43 % 1.60 – 2.73 % Expected volatility 84.93 – 116.81 % 97.91 – 107.01 % Weighted average expected volatility 89.26 % 101.52 % Expected lives (in years) 5.20 – 10.00 5.20 – 10.00 Expected dividend yield 0.00 % 0.00 % The weighted-average fair value of options granted during the years ended December 31, 2015 and 2014 was $0.41 and $2.43 per share, respectively. The risk-free interest rate used for each grant was based upon the yield on zero-coupon U.S. Treasury securities with a term similar to the expected life of the related option. The Company’s expected stock price volatility assumption is based upon the volatility of a composition of comparable companies. The expected life assumption for employee grants was based upon the simplified method provided for under ASC 718 and the expected life assumption for non-employees was based upon the contractual term of the option. The dividend yield assumption of zero is based upon the fact that the Company has never paid cash dividends and presently has no intention of paying cash dividends. The following table summarizes the activity of the Company’s stock option plan for the period from January 1, 2015 to December 31, 2015: Total Number of Shares Weighted- Average Exercise Price Per Share Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value Balance at January 1, 2015 3,000,264 $ 3.39 Granted 405,164 0.55 Exercised — — Cancelled (81,667 ) 3.07 Balance at December 31, 2015 3,323,761 $ 3.05 7.15 years $ — Exercisable at December 31, 2015 2,501,807 $ 3.29 6.78 years $ — Stock-based compensation expense for the years ended December 31, 2015 and 2014 was approximately $1,535,000 and $1,846,000, respectively. Of this, the Company recognized approximately $16,800 of income and $81,000 of expense related to non-employee stock options for the same period. There is no income tax benefit as the Company is currently operating at a loss and an actual income tax benefit may not be realized. As of December 31, 2015, the compensation expense for all unvested stock options in the amount of approximately $1,200,000 will be recognized in the Company’s results of operations over a weighted average period of 1.68 years.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes For the years ending December 31, 2015 and 2014, all of the Company’s loss before income taxes was generated in the United States. The components of federal and state income tax expense are as follows (in thousands): Year Ended December 31, 2015 2014 Current Federal $ — $ — State — — Total current — — Deferred Federal (3,157 ) (2,727 ) State (803 ) (583 ) Total deferred (3,960 ) (3,310 ) Valuation allowance 3,960 3,310 Total income tax expense $ — $ — The differences between the income taxes expected at the Federal statutory income tax rate and the reported income tax (benefit) expense is as follows: 2015 2014 Federal statutory rate 34.0 % 34.0 % State income taxes, net of federal benefit 4.8 4.2 Non-deductible expenses (1.9 ) (2.1 ) Income tax credits 1.9 1.6 Valuation allowance (38.8 ) (37.7 ) Effective tax rate 0.0 % 0.0 % As of December 31, 2015, the Company elected to early adopt ASU 2015-17 issued by the FASB in November 2015. ASU 2015-17 simplifies the presentation of deferred income taxes by requiring that deferred tax assets and liabilities be classified as noncurrent on the balance sheet. The Company early adopted the guidance on a prospective basis. There was no impact to the financial statements as a result of this change. The components of net deferred tax assets are as follows (in thousands): As of December 31, 2015 2014 Net operating loss carryforwards $ 13,552 $ 9,805 Tax credit carryforwards 442 261 Stock-based compensation 1,744 1,392 Licensing deduction deferral 5,979 6,367 Other timing differences 178 110 Gross deferred tax assets 21,895 17,935 Valuation allowance (21,895 ) (17,935 ) Net deferred tax asset $ — $ — The Company’s deferred tax assets at December 31, 2015 and 2014 consisted primarily of its net operating loss carryforwards, deferred compensation, tax credit carryforwards, intangible assets capitalized for federal income tax purposes and certain accruals that for tax purposes are not deductible until future payment is made. The valuation allowance increased $3,960,000 and $3,310,000 for the years ended December 31, 2015 and 2014, respectively, and is primarily attributable to an increase in net operating losses, tax credits and stock-based compensation in 2015. The Company has incurred net operating losses since inception. At December 31, 2015, the Company had federal and state net operating loss carryforwards of approximately $35,300,000 and $29,700,000, respectively, which are available to reduce future taxable income through 2035. In addition, the Company has federal and state research credits of $331,000 and $168,000, respectively, to offset future tax expense through 2035. 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 full deferred income tax valuation allowance has been recorded against these assets. Under the provisions of the Internal Revenue Code, certain substantial changes in the Company’s ownership may result in a limitation on the amount of net operating loss carryforwards and research and development credit carryforwards which could be utilized annually to offset future taxable income and taxes payable. The Company has not yet performed an analysis to determine if one or multiple ownership changes may have occurred in the past. The Company files income tax returns in the United States, Massachusetts and New Jersey. The Company is subject to tax examinations for Federal and state purposes tax years 2012 through 2015. The Company has not recorded any uncertain tax positions as of December 31, 2015 or 2014. The Company does not believe there will be any material changes in its unrecognized tax positions over the next 12 months. The Company has not incurred any interest or penalties. In the event that the Company is assessed interest or penalties at some point in the future, they will be classified in the financial statements as general and administrative expenses.

License Agreements

License Agreements	12 Months Ended
	Dec. 31, 2015
Research and Development [Abstract]
License Agreements	12. License Agreements As part of its business, the Company enters into licensing agreements with third parties that often require milestone and royalty payments based on the progress of the asset through development stages. Milestone payments may be required, for example, upon approval of the product for marketing by a regulatory agency. In certain agreements, the Company is required to make royalty payments based upon a percentage of the sales of the products licensed pursuant to such agreements. The expenditures required under these arrangements may be material individually in the event that the Company develops product candidates covered by the intellectual property licensed under any such arrangement, 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 addition, these arrangements often give the Company discretion to unilaterally terminate development of the product, which would allow the Company to avoid making the contingent payments; however, the Company is unlikely to cease development if the compound successfully achieves clinical testing objectives. Advirna. Our rights under the Advirna agreement will expire upon the later of: (i) the expiration of the last-to-expire of the “patent rights” (as defined) included in the Advirna agreement; or (ii) the abandonment of the last-to-be abandoned of such patents, unless earlier terminated in accordance with the provisions of the agreement. We may terminate the Advirna agreement at any time upon 90 days’ written notice to Advirna, and Advirna may terminate the agreement upon 90 days’ prior written notice in the event that we cease using commercially reasonable efforts to research, develop, license or otherwise commercialize the patent rights or “royalty-bearing products” (as defined), provided that we may refute such claim within such 90-day period by showing budgeted expenditures for the research, development, licensing or other commercialization consistent with other technologies of similar stage of development and commercial potential as the patent rights or royalty-bearing products. Further, either party at any time may provide to the other party written notice of a material breach of the agreement. If the other party fails to cure the identified breach within 90 days after the date of the notice, the aggrieved party may terminate the agreement by written notice to the party in breach. Hapten DPCP Under the Assignment and License Agreement, Hapten received at closing an upfront payment from us, paid in cash and stock, and will be entitled to receive: (i) future milestone payments tied to the achievement of certain clinical and commercial objectives (all of which payments may be made at our option in cash or through the issuance of common stock); and (ii) escalating royalties based on product sales by us and any sublicensees. The Assignment and License Agreement with Hapten is described further in Note 8.

Summary of Significant Accoun21

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“ GAAP
Uses of Estimates in Preparation of Financial Statements	Uses of Estimates in Preparation of Financial Statements The preparation of financial statements in accordance 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 revenues and expenses during the reporting period. Actual results could differ materially from these estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid debt instruments with an original maturity of three months or less to be cash equivalents. Cash equivalents consist primarily of amounts invested in certificates of deposit.
Restricted Cash	Restricted Cash Restricted cash consists of certificates of deposit held by financial institutions as collateral for the Company’s corporate credit cards.
Short-term Investments	Short-term Investments Short-term investments consist of certificates of deposit with original maturities ranging from three months to one year.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and short-term investments. The Company maintains cash balances in several accounts with one bank, which at times are in excess of federally insured limits. The Company has established guidelines related to credit ratings and maturities intended to safeguard principal balances and maintain liquidity. The Company’s investments are maintained in accordance with the Company’s investment policy, which defines allowable investments, specifies credit quality standards and limits the exposure of any single issuer.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amounts reported in the balance sheet for cash equivalents, restricted cash, short-term investments and accounts payable approximate their fair values due to their short-term nature or market rates of interest.
Property and Equipment	Property and Equipment Property and equipment are stated at cost and depreciated using the straight-line method based on the estimated useful lives of the related assets. The Company provides for depreciation over the assets’ estimated useful lives as follows: Computer equipment 3 years Machinery & equipment 5 years Office furniture 5 years Depreciation and amortization expense for the years ended December 31, 2015 and 2014 was approximately $77,000 and $87,000, respectively.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews long-lived assets for impairment on an interim basis if an event occurs that might reduce the fair value of such assets below their carrying values. An impairment loss would be recognized based on the difference between the carrying value of the asset and its estimated fair value, which would be determined based on either discounted future cash flows or other appropriate fair value methods. The Company believes no impairment existed as of December 31, 2015 and 2014.
Revenue Recognition	Revenue Recognition Revenue is recognized when there is persuasive evidence of an arrangement, the fee is fixed or determinable, delivery has occurred or services have been rendered and collection of the related receivable is reasonably assured. The Company may generate revenue from product sales, license agreements, collaborative research and development arrangements and government grants. The Company’s principal source of revenue consists of government research grants. Revenue from a government grant is recognized over the respective contract periods as the services are performed. Payments received prior to the recognition of revenue are recorded as deferred revenue.
Research and Development Expenses	Research and Development Expenses Research and development costs are charged to expense as incurred and relate to salaries, employee benefits, facility-related expenses, supplies, stock-based compensation related to employees and non-employees involved in the Company’s research and development, external services, other operating costs and overhead related to our research and development departments, costs to acquire technology licenses and expenses associated with preclinical activities and our clinical trials. Payments made by the Company in advance for research and development services not yet provided and/or for materials not yet received are recorded as prepaid expenses. Accrued liabilities are recorded related to those expenses for which vendors have not yet billed us with respect to services provided and/or materials that we have received. Preclinical and clinical trial expenses relate to third-party services, subject-related fees at the sites where our clinical trials are being conducted, laboratory costs, analysis costs, toxicology studies and investigator fees. Costs associated with these expenses are generally payable on the passage of time or when certain milestones are achieved. Expense is recorded during the period incurred or in the period in which a milestone is achieved. In order to ensure that we have adequately provided for preclinical and clinical expenses during the proper period, we maintain an accrual to cover these expenses. These accruals are assessed on a quarterly basis and are based on such assumptions as expected total cost, the number of subjects and clinical trial sites and length of the study. Actual results may differ from these estimates and could have a material impact on our reported results. Our historical accrual estimates have not been materially different from our actual costs. Although the Company believes that its patents and underlying technology have continuing value, the amount of future benefits to be derived from the patents is uncertain. Patent costs are, therefore, expensed as research and development costs as incurred.
Stock-based Compensation	Stock-based Compensation The Company follows the provisions of the Financial Accounting Standards Board (“ FASB ASC Compensation — Stock Compensation ASC 718 For stock options granted as consideration for services rendered by non-employees, the Company recognizes compensation expense in accordance with the requirements of FASB ASC Topic 505-50, “ Equity Based Payments to Non-Employees
Income Taxes	Income Taxes The Company recognizes assets or liabilities for the deferred tax consequences of temporary differences between the tax basis of assets or liabilities and their reported amounts in the financial statements in accordance with FASB ASC Topic 740, “Accounting for Income Taxes” ASC 740 .
Comprehensive Loss	Comprehensive Loss The Company’s comprehensive loss is equal to its net loss for all periods presented.
Net loss per Share	Net loss per Share The Company accounts for and discloses net loss per share attributable to common stockholders in accordance with FASB ASC Topic 260, “ Earnings per Share.”

Summary of Significant Accoun22

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Depreciation Over Assets' Estimated Useful Lives	The Company provides for depreciation over the assets’ estimated useful lives as follows: Computer equipment 3 years Machinery & equipment 5 years Office furniture 5 years

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Financial assets measured at fair value on a recurring basis are summarized as follows, in thousands: Description December 31, 2015 Quoted Prices In Active Markets (Level 1) Other Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 2,500 — 2,500 — Short-term investments 5,500 — 5,500 — Total $ 8,050 $ — $ 8,050 $ — Description December 31, 2014 Quoted Prices In Active Markets (Level 1) Other Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 4,000 — 4,000 — Total $ 4,050 $ — $ 4,050 $ —

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consist of the following, in thousands: December 31, 2015 2014 Employee compensation and benefits $ 725 $ 528 Clinical development expenses 225 186 Professional fees 126 165 Research and development costs 20 118 Other 10 5 Total accrued expenses $ 1,106 $ 1,002

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Future Cash Payments Under Contractual License Obligations	The Company’s contractual license obligations that will require future cash payments as of December 31, 2015 are as follows, in thousands: Year Ending December 31, 2016 $ 200 2017 200 2018 200 2019 165 2020 165 Thereafter 966 Total $ 1,896
Future Minimum Payments Under Operating Leases	At December 31, 2015, the Company’s future minimum payments required under operating leases are as follows, in thousands: Year Ending December 31, 2016 $ 120 2017 117 2018 120 2019 30 Total $ 387

Net Loss per Share Attributab26

Net Loss per Share Attributable to Common Stockholders (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Common Shares Excluded from the Calculation of Net Loss per Common Share Attributable to Common Stockholders	The following table sets forth the potential common shares excluded from the calculation of net loss per common share attributable to common stockholders because their inclusion would be anti-dilutive: December 31, 2015 2014 Options to purchase common stock 3,323,761 3,000,264 Common stock underlying Series A and Series A-1 convertible preferred stock — 16,300,969 Warrants to purchase common stock 25,569,615 4,615 Total 28,893,376 19,305,848

Stock-based Compensation (Table

Stock-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Assumptions Used to Determine Fair Value of Option Grants	The Company uses the Black-Scholes option-pricing model to determine the fair value of all its option grants. For valuing options granted for the years ended December 31, 2015 and 2014, the following assumptions were used: Year Ended December 31, 2015 2014 Risk-free interest rate 1.47 – 2.43 % 1.60 – 2.73 % Expected volatility 84.93 – 116.81 % 97.91 – 107.01 % Weighted average expected volatility 89.26 % 101.52 % Expected lives (in years) 5.20 – 10.00 5.20 – 10.00 Expected dividend yield 0.00 % 0.00 %
Summary of Stock Option Activity	The following table summarizes the activity of the Company’s stock option plan for the period from January 1, 2015 to December 31, 2015: Total Number of Shares Weighted- Average Exercise Price Per Share Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value Balance at January 1, 2015 3,000,264 $ 3.39 Granted 405,164 0.55 Exercised — — Cancelled (81,667 ) 3.07 Balance at December 31, 2015 3,323,761 $ 3.05 7.15 years $ — Exercisable at December 31, 2015 2,501,807 $ 3.29 6.78 years $ —

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Components of Federal and State Income Tax Expense	The components of federal and state income tax expense are as follows (in thousands): Year Ended December 31, 2015 2014 Current Federal $ — $ — State — — Total current — — Deferred Federal (3,157 ) (2,727 ) State (803 ) (583 ) Total deferred (3,960 ) (3,310 ) Valuation allowance 3,960 3,310 Total income tax expense $ — $ —
Effect Income Tax Rate Reconciliation	The differences between the income taxes expected at the Federal statutory income tax rate and the reported income tax (benefit) expense is as follows: 2015 2014 Federal statutory rate 34.0 % 34.0 % State income taxes, net of federal benefit 4.8 4.2 Non-deductible expenses (1.9 ) (2.1 ) Income tax credits 1.9 1.6 Valuation allowance (38.8 ) (37.7 ) Effective tax rate 0.0 % 0.0 %
Components of Net Deferred Tax Assets	The components of net deferred tax assets are as follows (in thousands): As of December 31, 2015 2014 Net operating loss carryforwards $ 13,552 $ 9,805 Tax credit carryforwards 442 261 Stock-based compensation 1,744 1,392 Licensing deduction deferral 5,979 6,367 Other timing differences 178 110 Gross deferred tax assets 21,895 17,935 Valuation allowance (21,895 ) (17,935 ) Net deferred tax asset $ — $ —

Summary of Significant Accoun29

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Summary Of Significant Accounting Policies [Line Items]
Depreciation and amortization	$ 77,000	$ 87,000
Impairment of long lived assets	$ 0	$ 0
Cash and Cash Equivalents [Member]
Summary Of Significant Accounting Policies [Line Items]
Liquid instrument maturity period	Three months or less
Short-term Investments [Member]
Summary Of Significant Accounting Policies [Line Items]
Liquid instrument maturity period	Three months to one year

Summary of Significant Accoun30

Summary of Significant Accounting Policies - Summary of Depreciation Over Assets' Estimated Useful Lives (Detail)	12 Months Ended
	Dec. 31, 2015
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of assets	3 years
Machinery & Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of assets	5 years
Office Furniture [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of assets	5 years

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measurements (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Assets:
Restricted cash	$ 50	$ 50
Short-term investments	5,500
Fair Value, Measurements, Recurring [Member]
Assets:
Restricted cash	50	50
Cash equivalents	2,500	4,000
Short-term investments	5,500
Total	8,050	4,050
Fair Value, Measurements, Recurring [Member] | Other Significant Observable Inputs (Level 2) [Member]
Assets:
Restricted cash	50	50
Cash equivalents	2,500	4,000
Short-term investments	5,500
Total	$ 8,050	$ 4,050

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accrued Liabilities and Other Liabilities [Abstract]
Employee compensation and benefits	$ 725	$ 528
Clinical development expenses	225	186
Professional fees	126	165
Research and development costs	20	118
Other	10	5
Total accrued expenses	$ 1,106	$ 1,002

Commitments and Contingencies -

Commitments and Contingencies - Future Cash Payments Under Contractual License Obligations (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 200
2,017	200
2,018	200
2,019	165
2,020	165
Thereafter	966
Total	$ 1,896

Commitments and Contingencies34

Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Lease agreement maturity date	Mar. 31, 2019
Monthly rental expense	$ 9,500
Operating lease expenses	$ 118,000	$ 107,500

Commitments and Contingencies35

Commitments and Contingencies - Future Minimum Payments Under Operating Leases (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 120
2,017	117
2,018	120
2,019	30
Total	$ 387

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Detail) - USD ($)	May. 27, 2015	Dec. 31, 2015	Dec. 31, 2014	Nov. 06, 2015	Dec. 31, 2013
Temporary Equity [Line Items]
Number of common stock issued upon conversion of convertible instrument		435,000
Common Stock [Member]
Temporary Equity [Line Items]
Number of common stock issued upon conversion of convertible instrument		16,610,303	9,463,712
Series A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Series A Preferred Stock, shares outstanding		0	5,110
Dividends issued on Preferred Stock	0	105	356
Fair value of Series A Preferred Stock dividends		$ 172,000	$ 2,399,000
Conversion of preferred stock into common shares	0	3,215	166
Preferred stock, accelerated dividend payment date		May 27, 2015
Number of common stock issued upon conversion of convertible instrument		(3,215)	(166)
Preferred Stock, shares eliminated				15,000
Series A Preferred Stock, shares authorized		0	15,000
Series A Preferred Stock, shares issued		0	5,110		7,920
Series A Convertible Preferred Stock [Member] | Common Stock [Member]
Temporary Equity [Line Items]
Number of common stock issued upon conversion of convertible instrument		7,837,400	405,720
Tang Capital Partners, L.P. ("TCP") [Member]
Temporary Equity [Line Items]
Dividend payment terms		On May 22, 2015, the Company entered into an agreement (the “Acceleration and Conversion Agreement”) with Tang Capital Partners, L.P. (“TCP”) pursuant to which the Company and TCP agreed to accelerate the next dividend payment date from June 30, 2015 to no later than May 29, 2015, and upon payment of such dividend immediately convert the dividend shares into common stock. In connection therewith, the dividend payment date was accelerated to May 27, 2015. There were no shares of Series A convertible preferred stock (“Series A Preferred Stock”) outstanding after the completion of the Acceleration and Conversion Agreement.
Tang Capital Partners, L.P. ("TCP") [Member] | Series A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Series A Preferred Stock, shares outstanding		0

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	Jun. 02, 2015	May. 27, 2015	Feb. 04, 2015	Dec. 18, 2014	Apr. 22, 2014	Dec. 31, 2015	Dec. 31, 2014	Nov. 06, 2015
Class of Stock [Line Items]
Preferred stock, par value						$ 0.0001	$ 0.0001
Preferred stock, shares authorized						10,000,000	10,000,000
Common stock, par value						$ 0.0001	$ 0.0001
Common stock, shares authorized						100,000,000	100,000,000
Fair value of Series A and Series A-1 convertible preferred stock dividends						$ 209,000	$ 4,130,000
Number of common stock issued upon conversion of convertible instrument						435,000
Fair value of common stock issued in exchange for patent and technology rights						$ 228,000
Sale of units, price per unit	$ 0.40
Units issued, shares	26,000,000
Description of transaction	Each unit consists of one share of common stock, a 13-month overallotment purchase right to purchase one-half of one share of common stock at a price of $0.455 per full share of common stock (the "Overallotment Purchase Rights") and a five-year warrant to purchase one-half of one share of common stock at a price of $0.52 per full share of common stock (the "Warrants").
Gross proceeds from public offering	$ 10,400,000
Net proceeds from the issuance of common stock	$ 9,200,000					9,266,000	$ 1,886,000
Gross proceeds from warrants exercised						$ 198,000
Series A-1 Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Series A-1 Preferred Stock, shares outstanding						0	1,578
Dividends issued on Preferred Stock		0				21	240
Fair value of Series A and Series A-1 convertible preferred stock dividends						$ 37,000	$ 1,731,000
Conversion of preferred stock into common shares		0				3,599	3,716
Preferred stock, accelerated dividend payment date						May 27, 2015
Number of common stock issued upon conversion of convertible instrument						(3,599)	(3,716)
Preferred Stock, shares eliminated								10,000
Series A-1 Preferred Stock, shares authorized						0	10,000
Series A-1 Preferred Stock, shares issued						0	1,578
Lincoln Park Capital Fund, LLC [Member]
Class of Stock [Line Items]
Common stock, shares issued							500,000
Stock reserved during period, value				$ 10,800,000	$ 20,000,000
Stock issued as a commitment fee, shares				100,000			100,000
Sale of units, price per unit				$ 1.93			$ 4
Tang Capital Partners, L.P. ("TCP") [Member]
Class of Stock [Line Items]
Series A-1 Preferred Stock, shares outstanding						0
Dividend payment terms						On May 22, 2015, the Company entered into an agreement (the “Acceleration and Conversion Agreement”) with Tang Capital Partners, L.P. (“TCP”) pursuant to which the Company and TCP agreed to accelerate the next dividend payment date from June 30, 2015 to no later than May 29, 2015, and upon payment of such dividend immediately convert the dividend shares into common stock. In connection therewith, the dividend payment date was accelerated to May 27, 2015. There were no shares of Series A convertible preferred stock (“Series A Preferred Stock”) outstanding after the completion of the Acceleration and Conversion Agreement.
Hapten Pharmaceuticals, LLC [Member]
Class of Stock [Line Items]
License fee			$ 100,000			$ 100,000
Fair value of common stock issued in exchange for patent and technology rights						$ 228,000
Common Stock [Member]
Class of Stock [Line Items]
Number of common stock issued upon conversion of convertible instrument						16,610,303	9,463,712
Common stock, shares issued						50,000	700,000
Common Stock [Member] | Series A-1 Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Number of common stock issued upon conversion of convertible instrument						8,772,903	9,057,992
Common Stock [Member] | Lincoln Park Capital Fund, LLC [Member]
Class of Stock [Line Items]
Common stock, shares issued						50,000
Net proceeds from the issuance of common stock						$ 64,000	$ 1,900,000
Common Stock [Member] | Hapten Pharmaceuticals, LLC [Member]
Class of Stock [Line Items]
Common stock, shares issued			200,000
Overallotment Purchase Rights [Member]
Class of Stock [Line Items]
Sale of stock, price per share	$ 0.455
Warrants to Purchase Common Stock [Member]
Class of Stock [Line Items]
Sale of stock, price per share	$ 0.52

Net Loss per Share Attributab38

Net Loss per Share Attributable to Common Stockholders - Common Shares Excluded from the Calculation of Net Loss per Common Share Attributable to Common Stockholders (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total amount of anti-dilutive securities excluded from computation of earnings per share	28,893,376	19,305,848
Options to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total amount of anti-dilutive securities excluded from computation of earnings per share	3,323,761	3,000,264
Common Stock Underlying Series A and Series A-1 Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total amount of anti-dilutive securities excluded from computation of earnings per share		16,300,969
Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total amount of anti-dilutive securities excluded from computation of earnings per share	25,569,615	4,615

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Detail) - USD ($)	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Shares reserved for issuance	5,000,000	5,000,000
Purchase of common stock	3,323,761	3,323,761	3,000,264
Shares of common stock available for future grants	1,674,239	1,674,239
Expiration period of Option		10 years
Description of stock option granted		Stock options granted by the Company to employees may have different vesting parameters, but generally vest within 48 months after the option grant date and expire within ten years of issuance.
Vesting period of option		48 months
Weighted average grant date fair value per share of options granted		$ 0.41	$ 2.43
Expected dividend yield		0.00%	0.00%
Stock-based compensation expense		$ 1,535,000	$ 1,846,000
Nonemployee share based compensation expense (income)		16,800	$ 81,000
Stock-based compensation expense tax benefit		0
Unrecognized share based compensation expense on unvested stock option	$ 1,200,000	$ 1,200,000
Unrecognized share based compensation expense on unvested stock option period of recognition	1 year 8 months 5 days

Stock-based Compensation - Sche

Stock-based Compensation - Schedule of Assumptions Used to Determine Fair Value of Option Grants (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, Minimum	1.47%	1.60%
Risk-free interest rate, Maximum	2.43%	2.73%
Expected volatility, Minimum	84.93%	97.91%
Expected volatility, Maximum	116.81%	107.01%
Weighted average expected volatility	89.26%	101.52%
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected lives (in years)	5 years 2 months 12 days	5 years 2 months 12 days
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected lives (in years)	10 years	10 years

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Stock Option Activity (Detail)	12 Months Ended
	Dec. 31, 2015USD ($)$ / sharesshares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total Number of Shares, Beginning Balance | shares	3,000,264
Total Number of Shares, Granted | shares	405,164
Total Number of Shares, Exercised | shares	0
Total Number of Shares, Cancelled | shares	(81,667)
Total Number of Shares, Ending Balance | shares	3,323,761
Total Number of Shares, Exercisable | shares	2,501,807
Weighted-Average Exercise Price Per Share, Beginning Balance | $ / shares	$ 3.39
Weighted-Average Exercise Price Per Share, Granted | $ / shares	0.55
Weighted-Average Exercise Price Per Share, Exercised | $ / shares	0
Weighted-Average Exercise Price Per Share, Cancelled | $ / shares	3.07
Weighted-Average Exercise Price Per Share, Ending Balance | $ / shares	3.05
Weighted-Average Exercise Price Per Share, Exercisable | $ / shares	$ 3.29
Weighted-Average Remaining Contractual Term, Ending Balance	7 years 1 month 24 days
Weighted-Average Remaining Contractual Term, Exercisable	6 years 9 months 11 days
Aggregate Intrinsic Value, Ending Balance | $	$ 0
Aggregate Intrinsic Value, Exercisable | $	$ 0

Income Taxes - Components of Fe

Income Taxes - Components of Federal and State Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Current
Federal	$ 0	$ 0
State	0	0
Total current	0	0
Deferred
Federal	(3,157)	(2,727)
State	(803)	(583)
Total deferred	(3,960)	(3,310)
Valuation allowance	3,960	3,310
Total income tax expense	$ 0	$ 0

Income Taxes - Effect Income Ta

Income Taxes - Effect Income Tax Rate Reconciliation (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Federal statutory rate	34.00%	34.00%
State income taxes, net of federal benefit	4.80%	4.20%
Non-deductible expenses	(1.90%)	(2.10%)
Income tax credits	1.90%	1.60%
Valuation allowance	(38.80%)	(37.70%)
Effective tax rate	0.00%	0.00%

Income Taxes - Components of Ne

Income Taxes - Components of Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 13,552	$ 9,805
Tax credit carryforwards	442	261
Stock-based compensation	1,744	1,392
Licensing deduction deferral	5,979	6,367
Other timing differences	178	110
Gross deferred tax assets	21,895	17,935
Valuation allowance	(21,895)	(17,935)
Net deferred tax asset	$ 0	$ 0

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Line Items]
Valuation allowance	$ (3,960,000)	$ (3,310,000)
Expiration of carry forwards loss	2,035
Research tax credit expiration period	2,035
Liability for uncertain tax positions	$ 0	$ 0
Federal Income Tax [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	35,300,000
Research tax credit	331,000
State Income Tax [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	29,700,000
Research tax credit	$ 168,000
Earliest Tax Year [Member]
Income Tax Disclosure [Line Items]
Open tax year subject to tax examination	2,012
Latest Tax Year [Member]
Income Tax Disclosure [Line Items]
Open tax year subject to tax examination	2,015

License Agreements - Additional

License Agreements - Additional Information (Detail) - Advirna [Member] - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Annual maintenance fee	$ 100,000
Royalty payments	1.00%
Effective license period	90 days
Research and Development Expenses [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
One-time milestone payment		$ 350,000