Phio Pharmaceuticals (PHIO) 10-Q 12 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Aug. 07, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Trading Symbol	RXII
Entity Registrant Name	RXi Pharmaceuticals Corp
Entity Central Index Key	1,533,040
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		64,949,121

Condensed Balance Sheets (Unaud

Condensed Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 5,986	$ 8,496
Restricted cash	50	50
Short-term investments	8,000
Prepaid expenses and other current assets	718	442
Total current assets	14,754	8,988
Property and equipment, net	181	183
Other assets	18	18
Total assets	14,953	9,189
Current liabilities:
Accounts payable	635	285
Accrued expenses and other current liabilities	1,187	1,002
Deferred revenue		47
Total current liabilities	$ 1,822	$ 1,334
Commitments and contingencies
Stockholders' equity:
Preferred stock	$ 0	$ 0
Common stock, $0.0001 par value, 100,000,000 shares authorized; 64,949,121 and 21,984,272 shares issued and outstanding at June 30, 2015 and December 31, 2014, respectively	6	2
Additional paid-in capital	65,118	48,047
Accumulated deficit	(51,993)	(46,882)
Total stockholders' equity	13,131	2,745
Total liabilities, convertible preferred stock and stockholders' equity	$ 14,953	9,189
Series A Convertible Preferred Stock [Member]
Convertible preferred stock:
Series A convertible preferred stock, $0.0001 par value, 15,000 shares authorized; 0 and 5,110 shares issued and outstanding at June 30, 2015 and December 31, 2014, respectively (at liquidation value)		5,110
Series A-1 Convertible Preferred Stock [Member]
Stockholders' equity:
Preferred stock		$ 1,578

Condensed Balance Sheets (Unau3

Condensed Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2015	Dec. 31, 2014
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	64,949,121	21,984,272
Common stock, shares outstanding	64,949,121	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	15,000	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]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000	10,000
Series A-1 Preferred Stock, shares issued	0	1,578
Series A-1 Preferred Stock, shares outstanding	0	1,578

Condensed Statements of Operati

Condensed Statements of Operations (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Net revenue			$ 12	$ 34	$ 41
Operating expenses:
Research and development expenses	[1]	$ 1,361	1,183	3,468	2,659
General and administrative expenses	[1]	804	850	1,677	1,693
Total operating expenses		2,165	2,033	5,145	4,352
Operating loss		(2,165)	(2,021)	(5,111)	(4,311)
Other income (expense)
Interest income, net		1	5	2	11
Other income (expense), net		(2)	10	(2)	10
Total other income (expense)		(1)	15		21
Net loss		(2,166)	(2,006)	(5,111)	(4,290)
Series A and Series A-1 convertible preferred stock dividends		(24)	(1,213)	(209)	(2,968)
Net loss applicable to common stockholders		$ (2,190)	$ (3,219)	$ (5,320)	$ (7,258)
Net loss per common share applicable to common stockholders
Basic and diluted		$ (0.05)	$ (0.23)	$ (0.16)	$ (0.54)
Weighted average common shares: basic and diluted		44,190,583	14,015,451	34,033,463	13,319,634
[1]	Non-cash stock-based compensation expenses included in operating expenses are as follows: Research and development $ 204 $ 206 $ 378 $ 416 General and administrative 244 251 481 532

Condensed Statements of Operat5

Condensed Statements of Operations (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Research and Development Expense [Member]
Non-cash stock-based compensation expenses	$ 203	$ 206	$ 378	$ 416
General and Administrative Expense [Member]
Non-cash stock-based compensation expenses	$ 244	$ 251	$ 480	$ 532

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net loss	$ (5,111)	$ (4,290)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	41	42
Gain on disposal of equipment		(10)
Non-cash stock-based compensation	858	948
Fair value of common stock issued in exchange for patent and technology rights	228
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(276)	(64)
Accounts payable	350	130
Accrued expenses and other current liabilities	185	(1,113)
Deferred revenue	(47)	(40)
Net cash used in operating activities	(3,772)	(4,397)
Cash flows from investing activities:
Purchase of short-term investments	(8,000)
Maturities of short-term investments		3,000
Cash paid for purchase of property and equipment	(39)	(71)
Proceeds from disposal of property and equipment		12
Net cash (used in) provided by investing activities	(8,039)	2,941
Cash flows from financing activities:
Net proceeds from the issuance of common stock	9,254	1,947
Proceeds from the issuance of common stock upon the exercise of warrants	16
Proceeds from the issuance of common stock in connection with the employee stock purchase plan	31	30
Net cash provided by financing activities	9,301	1,977
Net increase (decrease) in cash and cash equivalents	(2,510)	521
Cash and cash equivalents at the beginning of period	8,496	11,390
Cash and cash equivalents at the end of period	5,986	11,911
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	3,000
Conversion of Series A and Series A-1 convertible preferred stock into common stock	6,814	1,025
Fair value of Series A and Series A-1 convertible preferred stock dividends	209	2,968
Series A and Series A-1 convertible preferred stock dividends	$ 127	$ 333

Nature of Business and Basis of

Nature of Business and Basis of Presentation	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Nature of Business and Basis of Presentation	1. Nature of Business and Basis of Presentation RXi Pharmaceuticals Corporation (“ RXi we our Company ® Basis of Presentation The accompanying condensed financial statements are unaudited and 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 from these estimates. Cash and Cash Equivalents The Company considers all highly liquid 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 3 months to 1 year. Revenue Recognition The principal source of revenue consists of government research grants. Revenue is recognized provided there is persuasive evidence of an arrangement, the fee is fixed or determinable and collection of the related receivable is reasonably assured, and no contingencies remain outstanding. 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. 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 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.” Comprehensive Loss The Company’s net loss is equal to its comprehensive loss for all periods presented. .

Recent Accounting Pronouncement

Recent Accounting Pronouncements	6 Months Ended
	Jun. 30, 2015
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	2. Recent Accounting Pronouncements In August 2014, the FASB issued Accounting Standards Update (“ ASU Presentation of Financial Statements — Going Concern (Topic 915): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.” In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers (Topic 606) ”

Net Loss per Share Attributable

Net Loss per Share Attributable to Common Stockholders	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Net Loss per Share Attributable to Common Stockholders	3. 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: June 30, 2015 2014 Options to purchase common stock 3,333,678 2,928,932 Common stock underlying Series A and Series A-1 convertible preferred stock — 22,626,163 Warrants to purchase common stock 25,969,615 4,615 Total 29,303,293 25,559,710

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 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 June 30, 2015 Quoted Other Unobservable Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 3,000 — 3,000 — Short-term investments 8,000 — 8,000 — Total $ 11,050 $ — $ 11,050 $ — Description December 31, 2014 Quoted Other Unobservable Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 4,000 — 4,000 — Total $ 4,050 $ — $ 4,050 $ — Fair Value of Financial Instruments The carrying amounts reported in the balance sheet for restricted cash, cash equivalents, short-term investments and accounts payable approximate their fair values due to their short-term nature.

Convertible Preferred Stock

Convertible Preferred Stock	6 Months Ended
	Jun. 30, 2015
Series A Convertible Preferred Stock [Member]
Convertible Preferred Stock	5. Convertible Preferred Stock The Company currently has authorized for issuance a total of 15,000 shares of Series A convertible preferred stock (“ Series A Preferred Stock Dividends Holders of Series A Preferred Stock are entitled to receive cumulative mandatory dividends at the rate per share of seven percent (7%) of the face amount ($1,000 per share) per annum, payable quarterly on each March 31, June 30, September 30 and December 31. Dividends shall be payable in additional shares of Series A Preferred Stock valued for this purpose at the face amount. The fair value of the Series A Preferred Stock dividend, which is included in the Company’s net loss applicable to common shareholders, is calculated by multiplying the number of common shares that a preferred holder would receive upon conversion by the closing price of the Company’s common stock on the dividend payment date. On May 22, 2015, the Company entered into an agreement (the “ Acceleration and Conversion Agreement TCP The Company paid dividends in additional shares of Series A Preferred Stock of 21 and 85 shares for the three months ended June 30, 2015 and 2014, respectively. Included in the Company’s net loss applicable to common shareholders related to the fair value of the Series A Preferred Stock dividends was $24,000 and $625,000 for the three months ended June 30, 2015 and 2014, respectively. The Company paid dividends in additional shares of Series A Preferred Stock of 105 and 181 shares for the six months ended June 30, 2015 and 2014, respectively. 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 $1,635,000 for the six months ended June 30, 2015 and 2014, respectively. Conversion Each holder of shares of Series A Preferred Stock may, at any time and from time to time, convert each of its shares into a number of fully paid and non-assessable shares of common stock at the defined conversion rate. Each share of Series A Preferred Stock is convertible into 2,437.57 shares of common stock. In no event shall any holder of shares of Series A Preferred Stock have the right to convert shares of Series A Preferred Stock into shares of common stock to the extent that, after giving effect to such conversion, the holder, together with any of its affiliates, would beneficially own more than 9.999% of the then-issued and outstanding shares of common stock. During the three months ended June 30, 2015, 3,106 shares of Series A Preferred Stock were converted into 7,571,218 shares of common stock and during the three months ended June 30, 2014, there were no shares of Series A Preferred Stock converted into shares of common stock. During the six months ended June 30, 2015, 3,215 shares of Series A Preferred Stock were converted into 7,837,400 shares of common stock and during the six months ended June 30, 2014, 166 shares of Series A Preferred Stock were converted into 405,720 shares of common stock. Exchange Transaction On March 20, 2015, the Company entered into an exchange agreement (the “ Exchange Agreement Series A-1 Preferred Stock

Stockholder's Equity

Stockholder's Equity	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Stockholder's Equity	6. 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 The Company currently has authorized for issuance a total of 10,000 shares of Series A-1 Preferred Stock, $0.0001 par value per share. There were no shares of Series A-1 Preferred Stock outstanding at June 30, 2015. Dividends Holders of Series A-1 Preferred Stock are entitled to receive cumulative mandatory dividends at the rate per share of seven percent (7%) of the face amount ($1,000 per share) per annum, payable quarterly on each March 31, June 30, September 30 and December 31. Dividends shall be payable in additional shares of Series A-1 Preferred Stock valued for this purpose at the face amount. The fair value of the Series A-1 Preferred Stock dividend, which is included in the Company’s net loss applicable to common shareholders, is calculated by multiplying the number of common shares that a preferred holder would receive upon conversion by the closing price of the Company’s common stock on the dividend payment date. 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. The Company paid an immaterial amount of dividends in additional shares of Series A-1 Preferred Stock for the three months ended June 30, 2015. The Company paid dividends in additional shares of Series A-1 Preferred Stock of 80 shares for the three months ended June 30, 2014, respectively. 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 $588,000 for the three months ended June 30, 2014. The Company paid dividends in additional shares of Series A-1 Preferred Stock of 21 and 152 shares for the six months ended June 30, 2015 and 2014, respectively. 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 $1,333,000 for the six months ended June 30, 2015 and 2014, respectively. Conversion Each holder of shares of Series A-1 Preferred Stock may, at any time and from time to time, convert each of its shares into a number of fully paid and non-assessable shares of common stock at the defined conversion rate. Each share of Series A-1 Preferred Stock is convertible into 2,437.57 shares of common stock. In no event shall any holder of shares of Series A-1 Preferred Stock have the right to convert shares of Series A-1 Preferred Stock into shares of common stock to the extent that, after giving effect to such conversion, the holder, together with any of its affiliates, would beneficially own more than 9.999% of the then-issued and outstanding shares of common stock. During the three months ended June 30, 2015, 21 shares of Series A-1 Preferred Stock were converted into 51,759 shares of common stock and during the three months ended June 30, 2014, 353 shares of Series A-1 Preferred Stock were converted into 860,457 shares of common stock. During the six months ended June 30, 2015, 3,599 shares of Series A-1 Preferred Stock were converted into 8,772,903 shares of common stock and during the six months ended June 30, 2014, 859 shares of Series A-1 Preferred Stock were converted into 2,093,859 shares of common stock. Exchange Transaction On March 20, 2015, the Company entered into the Exchange Agreement with TCP pursuant to which TCP exchanged a total of 2,000 shares of Series A Preferred Stock for a like number of shares of Series A-1 Preferred Stock. The terms of the Series A-1 Preferred Stock are identical in all respects to the Series A Preferred Stock, other than the elimination of cash penalties that would potentially be due and payable upon the failure of the Company to have enough shares of common stock available to permit the conversion of Series A Preferred Stock into common stock. The exchange transaction resulted in a decrease in the face value of the Series A Preferred Stock and a corresponding increase in the face value of the Series A-1 Preferred Stock. Common Stock Hapten License Agreement On December 17, 2014, the Company entered into an assignment and exclusive license agreement, (the “ Hapten Assignment and License Agreement Hapten Lincoln Park Capital Equity Line During the six months ended June 30, 2015, the Company sold a total of 50,000 shares of common stock for net proceeds of approximately $64,000 to Lincoln Park Capital Fund, LLC (“ LPC LPC Purchase Agreement 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 (“ ASC 480 ASC 815 During the three months ended June 30, 2015, 35,000 warrants had been exercised for gross proceeds of $16,000. There have been no other warrant exercises to date. Refer to the Series A Preferred Stock and Series A-1 Preferred Stock conversions described above in this Note and Note 5 for shares issued as a result of the conversions of Series A and Series A-1 Preferred Stock during the three and six months ended June 30, 2015 and 2014, respectively.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	7. Stock-Based Compensation 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 during the three and six months ended June 30, 2015 and 2014, the following assumptions were used: For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Risk-free interest rate 1.55 – 1.83 % 1.60 – 1.95 % 1.47 – 1.83 % 1.60 – 2.73 % Expected volatility 85.63 – 87.91 % 97.91 – 101.64 % 85.63 – 91.16 % 97.91 – 107.01 % Weighted average expected volatility 86.85 % 100.77 % 87.62 % 101.19 % Expected lives (in years) 5.20 – 6.25 5.20 – 6.25 5.20 – 6.25 5.20 – 10.0 Expected dividend yield 0.00 % 0.00 % 0.00 % 0.00 % The weighted average fair value of options granted during the three month periods ended June 30, 2015 and 2014 was $0.28 and $2.26, respectively. The weighted average fair value of options granted during the six month periods ended June 30, 2015 and 2014 was $0.41 and $2.42, 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 Company’s stock option plan for the period from January 1, 2015 to June 30, 2015: Total Number Weighted- Weighted- Aggregate Balance at January 1, 2015 3,000,264 $ 3.39 Granted 354,664 0.56 Exercised — — Cancelled (21,250 ) 2.86 Balance at June 30, 2015 3,333,678 $ 3.09 7.61 years $ 30,323 Exercisable at June 30, 2015 2,218,862 $ 3.38 7.19 years $ — Stock-based compensation expense for the three months ended June 30, 2015 and 2014 was approximately $447,000 and $457,000, respectively. Of this, the Company recognized approximately $5,300 of income and $9,600 of expense related to non-employee stock options for the same respective periods. Stock-based compensation expense for the six months ended June 30, 2015 and 2014 was approximately $858,000 and $948,000, respectively. Of this, the Company recognized approximately $21,800 of income and $46,600 of expense related to non-employee stock options for the same respective periods. Employee Stock Purchase Plan The Company’s Employee Stock Purchase Plan (“ ESPP The Company uses the Black-Scholes option-pricing model to determine the fair value of the ESPP stock rights. There were no stock rights issued during the three months ended June 30, 2015 and 2014. For valuing stock rights issued during the six months ended June 30, 2015 and 2014, the following assumptions were used: For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Risk-free interest rate N/A N/A 0.11 % 0.09 % Expected volatility N/A N/A 82.72 % 94.99 % Expected lives (in years) N/A N/A 0.50 0.50 Expected dividend yield N/A N/A 0.00 % 0.00 % The weighted average fair value of stock rights issued during the six months ended June 30, 2015 and 2014 was $0.58 and $1.14, respectively. The risk-free interest rate used 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 volatility is based upon the volatility of a composition of comparable companies for the expected term. The expected life assumption was based upon the purchase period and 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. Of the total stock-based compensation expense recorded for the three months ended June 30, 2015 and 2014, the Company recognized $6,500 and $6,600 of expense related to the ESPP for the same respective periods. Of the total stock-based compensation expense recorded for the six months ended June 30, 2015 and 2014, the Company recognized $13,000 and $13,200 of expense related to the ESPP for the same respective periods.

Nature of Business and Basis 14

Nature of Business and Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed financial statements are unaudited and 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 from these estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid 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 3 months to 1 year.
Revenue Recognition	Revenue Recognition The principal source of revenue consists of government research grants. Revenue is recognized provided there is persuasive evidence of an arrangement, the fee is fixed or determinable and collection of the related receivable is reasonably assured, and no contingencies remain outstanding. 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.
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
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.”
Comprehensive Loss	Comprehensive Loss The Company’s net loss is equal to its comprehensive loss for all periods presented.

Net Loss per Share Attributab15

Net Loss per Share Attributable to Common Stockholders (Tables)	6 Months Ended
	Jun. 30, 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: June 30, 2015 2014 Options to purchase common stock 3,333,678 2,928,932 Common stock underlying Series A and Series A-1 convertible preferred stock — 22,626,163 Warrants to purchase common stock 25,969,615 4,615 Total 29,303,293 25,559,710

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 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 June 30, 2015 Quoted Other Unobservable Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 3,000 — 3,000 — Short-term investments 8,000 — 8,000 — Total $ 11,050 $ — $ 11,050 $ — Description December 31, 2014 Quoted Other Unobservable Assets: Restricted cash $ 50 $ — $ 50 $ — Cash equivalents 4,000 — 4,000 — Total $ 4,050 $ — $ 4,050 $ —

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 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 during the three and six months ended June 30, 2015 and 2014, the following assumptions were used: For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Risk-free interest rate 1.55 – 1.83 % 1.60 – 1.95 % 1.47 – 1.83 % 1.60 – 2.73 % Expected volatility 85.63 – 87.91 % 97.91 – 101.64 % 85.63 – 91.16 % 97.91 – 107.01 % Weighted average expected volatility 86.85 % 100.77 % 87.62 % 101.19 % Expected lives (in years) 5.20 – 6.25 5.20 – 6.25 5.20 – 6.25 5.20 – 10.0 Expected dividend yield 0.00 % 0.00 % 0.00 % 0.00 %
Summary of Stock Option Activity	The following table summarizes the activity of Company’s stock option plan for the period from January 1, 2015 to June 30, 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 354,664 0.56 Exercised — — Cancelled (21,250 ) 2.86 Balance at June 30, 2015 3,333,678 $ 3.09 7.61 years $ 30,323 Exercisable at June 30, 2015 2,218,862 $ 3.38 7.19 years $ —
Schedule of Assumptions Used to Determine Fair Value of Employee Stock Purchase Plan Stock Rights	The Company uses the Black-Scholes option-pricing model to determine the fair value of the ESPP stock rights. There were no stock rights issued during the three months ended June 30, 2015 and 2014. For valuing stock rights issued during the six months ended June 30, 2015 and 2014, the following assumptions were used: For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Risk-free interest rate N/A N/A 0.11 % 0.09 % Expected volatility N/A N/A 82.72 % 94.99 % Expected lives (in years) N/A N/A 0.50 0.50 Expected dividend yield N/A N/A 0.00 % 0.00 %

Nature of Business and Basis 18

Nature of Business and Basis of Presentation - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2015
Cash and Cash Equivalents [Member]
Description of Business and Basis of Presentation [Line Items]
Liquid instrument maturity period	Three months or less
Short-term Investments [Member]
Description of Business and Basis of Presentation [Line Items]
Liquid instrument maturity period	3 months to 1 year

Net Loss per Share Attributab19

Net Loss per Share Attributable to Common Stockholders - Common Shares Excluded from Calculation of Net Loss per Common Share Attributable to Common Stockholders (Detail) - shares	6 Months Ended
	Jun. 30, 2015	Jun. 30, 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	29,303,293	25,559,710
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	3,333,678	2,928,932
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		22,626,163
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	25,969,615	4,615

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measurements (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Assets:
Restricted cash	$ 50	$ 50
Short-term investments	8,000
Fair Value, Measurements, Recurring [Member]
Assets:
Restricted cash	50	50
Cash equivalents	3,000	4,000
Short-term investments	8,000
Total	11,050	4,050
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Restricted cash	50	50
Cash equivalents	3,000	4,000
Short-term investments	8,000
Total	$ 11,050	$ 4,050

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Detail) - USD ($)	Mar. 20, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Class of Stock [Line Items]
Number of common stock issued upon conversion of convertible instrument		35,000
Tang Capital Partners, L.P. ("TCP") [Member]
Class of Stock [Line Items]
Dividend payment terms				On May 22, 2015, the Company entered into an agreement with Tang Capital Partners, L.P. ("TCP") pursuant to which the Company and TCP agreed to accelerate the dividend payment date to no later than May 29, 2015 and upon issuance immediately convert the dividend shares into common stock. For the three months ended June 30, 2015, the dividend payment date was accelerated to May 27, 2015.
Series A Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Series A Preferred Stock, shares authorized		15,000		15,000		15,000
Series A Preferred Stock, par value		$ 0.0001		$ 0.0001		$ 0.0001
Series A Preferred Stock, shares outstanding		0		0		5,110
Preferred stock, annual dividend rate				7.00%
Preferred stock, face amount		$ 1,000		$ 1,000
Dividends issued on Preferred Stock		21	85	105	181
Fair value of Series A Preferred Stock dividends		$ 24,000	$ 625,000	$ 172,000	$ 1,635,000
Preferred stock, conversion rate		2,437.57		2,437.57
Percentage of affiliates owning shares				9.999%
Conversion of preferred stock into common shares		3,106	0	3,215	166
Shares of Series A Preferred Stock exchanged for Series A-1 Preferred Stock	2,000
Series A Convertible Preferred Stock [Member] | Common Stock [Member]
Class of Stock [Line Items]
Number of common stock issued upon conversion of convertible instrument		7,571,218		7,837,400	405,720
Series A-1 Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, annual dividend rate				7.00%
Preferred stock, face amount		$ 1,000		$ 1,000
Dividends issued on Preferred Stock			80	21	152
Preferred stock, conversion rate		2,437.57		2,437.57
Percentage of affiliates owning shares				9.999%
Conversion of preferred stock into common shares		21	353	3,599	859
Shares of Series A Preferred Stock exchanged for Series A-1 Preferred Stock	2,000
Series A-1 Convertible Preferred Stock [Member] | Common Stock [Member]
Class of Stock [Line Items]
Number of common stock issued upon conversion of convertible instrument		51,759	860,457	8,772,903	2,093,859

Stockholder's Equity - Addition

Stockholder's Equity - Additional Information (Detail) - USD ($)	Jun. 02, 2015	Mar. 20, 2015	Feb. 04, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Class of Stock [Line Items]
Preferred stock, par value				$ 0.0001			$ 0.0001		$ 0.0001
Preferred stock, shares authorized				10,000,000			10,000,000		10,000,000
Common stock, par value				$ 0.0001			$ 0.0001		$ 0.0001
Common stock, shares authorized				100,000,000			100,000,000		100,000,000
Fair value of Series A and Series A-1 Preferred Stock dividends				$ 24,000		$ 1,213,000	$ 209,000	$ 2,968,000
Number of common stock issued upon conversion of convertible instrument				35,000
Research and development expenses							$ 228,000
Common stock, shares issued				64,949,121			64,949,121		21,984,272
Net proceeds from the issuance of common stock	$ 9,200,000						$ 9,254,000	$ 1,947,000
Units issued, shares	26,000,000
Sale of units, price per unit	$ 0.40
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
Gross proceeds from warrants exercised				$ 16,000			$ 16,000
Warrants to Purchase Common Stock [Member]
Class of Stock [Line Items]
Sale of stock, price per share	$ 0.52
Overallotment Purchase Rights [Member]
Class of Stock [Line Items]
Sale of stock, price per share	$ 0.455
Hapten Pharmaceuticals, LLC [Member]
Class of Stock [Line Items]
License fee			$ 100,000		$ 100,000
Research and development expenses					$ 228,000
Hapten Pharmaceuticals, LLC [Member] | Common Stock [Member]
Class of Stock [Line Items]
Common stock, shares issued			200,000
Tang Capital Partners, L.P. ("TCP") [Member]
Class of Stock [Line Items]
Dividend payment terms							On May 22, 2015, the Company entered into an agreement with Tang Capital Partners, L.P. ("TCP") pursuant to which the Company and TCP agreed to accelerate the dividend payment date to no later than May 29, 2015 and upon issuance immediately convert the dividend shares into common stock. For the three months ended June 30, 2015, the dividend payment date was accelerated to May 27, 2015.
Lincoln Park Capital Fund, LLC [Member] | Common Stock [Member]
Class of Stock [Line Items]
Common stock, shares issued				50,000			50,000
Net proceeds from the issuance of common stock				$ 0			$ 64,000
Series A-1 Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, par value				$ 0.0001			$ 0.0001		$ 0.0001
Preferred stock, shares authorized				10,000			10,000		10,000
Series A-1 Preferred Stock, shares outstanding				0			0		1,578
Preferred stock, annual dividend rate							7.00%
Preferred stock, face amount				$ 1,000			$ 1,000
Dividends issued on Preferred Stock						80	21	152
Fair value of Series A and Series A-1 Preferred Stock dividends						$ 588,000	$ 37,000	$ 1,333,000
Percentage of affiliates owning shares							9.999%
Preferred stock, conversion rate				2,437.57			2,437.57
Conversion of preferred stock into common shares				21		353	3,599	859
Shares of Series A Preferred Stock exchanged for Series A-1 Preferred Stock		2,000
Series A-1 Convertible Preferred Stock [Member] | Common Stock [Member]
Class of Stock [Line Items]
Number of common stock issued upon conversion of convertible instrument				51,759		860,457	8,772,903	2,093,859
Series A Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, annual dividend rate							7.00%
Preferred stock, face amount				$ 1,000			$ 1,000
Dividends issued on Preferred Stock				21		85	105	181
Percentage of affiliates owning shares							9.999%
Preferred stock, conversion rate				2,437.57			2,437.57
Conversion of preferred stock into common shares				3,106		0	3,215	166
Shares of Series A Preferred Stock exchanged for Series A-1 Preferred Stock		2,000
Series A Convertible Preferred Stock [Member] | Common Stock [Member]
Class of Stock [Line Items]
Number of common stock issued upon conversion of convertible instrument				7,571,218			7,837,400	405,720

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Assumptions Used to Determine Fair Value of Option Grants (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, Minimum	1.55%	1.60%	1.47%	1.60%
Risk-free interest rate, Maximum	1.83%	1.95%	1.83%	2.73%
Expected volatility, Minimum	85.63%	97.91%	85.63%	97.91%
Expected volatility, Maximum	87.91%	101.64%	91.16%	107.01%
Weighted average expected volatility	86.85%	100.77%	87.62%	101.19%
Expected dividend yield	0.00%	0.00%	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	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)	6 years 3 months	6 years 3 months	6 years 3 months	10 years

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value per share of options granted	$ 0.28	$ 2.26	$ 0.41	$ 2.42
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Stock-based compensation expense	$ 447,000	$ 457,000	$ 858,000	$ 948,000
Nonemployee share based compensation expense (income)	$ (5,300)	$ 9,600	(21,800)	46,600
Number of shares issued under ESPP	0	0
Stock-based compensation expense related to the ESPP	$ 6,500	$ 6,600	$ 13,000	$ 13,200
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value per share of options granted			$ 0.58	$ 1.14
Expected dividend yield			0.00%	0.00%
Percentage of common share offer price as to market price			90.00%
Shares reserved for issuance	113,333		113,333

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Option Activity (Detail) - Jun. 30, 2015 - USD ($)	Total
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total Number of Shares, Beginning Balance	3,000,264
Total Number of Shares, Granted	354,664
Total Number of Shares, Exercised	0
Total Number of Shares, Cancelled	(21,250)
Total Number of Shares, Ending Balance	3,333,678
Total Number of Shares, Exercisable	2,218,862
Weighted-Average Exercise Price Per Share, Beginning Balance	$ 3.39
Weighted-Average Exercise Price Per Share, Granted	0.56
Weighted-Average Exercise Price Per Share, Exercised	0
Weighted-Average Exercise Price Per Share, Cancelled	2.86
Weighted-Average Exercise Price Per Share, Ending Balance	3.09
Weighted-Average Exercise Price Per Share, Exercisable	$ 3.38
Weighted-Average Remaining Contractual Term, Ending Balance	7 years 7 months 10 days
Weighted-Average Remaining Contractual Term, Exercisable	7 years 2 months 9 days
Aggregate Intrinsic Value, Ending Balance	$ 30,323
Aggregate Intrinsic Value, Exercisable	$ 0

Stock-Based Compensation - Sc26

Stock-Based Compensation - Schedule of Assumptions Used to Determine Fair Value of Employee Stock Purchase Plan Stock Rights (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate			0.11%	0.09%
Expected volatility			82.72%	94.99%
Expected lives (in years)			6 months	6 months
Expected dividend yield			0.00%	0.00%