Description of Business and Basis of Presentation	6 Months Ended
Jun. 30, 2011
Description of Business and Basis of Presentation [Abstract]
Description of Business and Basis of Presentation	1. Description of Business and Basis of Presentation RXi Pharmaceuticals Corporation (NASDAQ: RXII) is a biotechnology company focused on discovering, developing and commercializing innovative therapies addressing major unmet medical needs using targeted biotherapeutics. RXi is pursuing the development of novel cancer therapeutics using peptide-based immunotherapy products, including our main product candidate, NeuVax™ (E75), for the treatment of various cancers. In this document, “we”, “our”, “ours”, “us”, “RXi”, and the “Company” refer to RXi Pharmaceuticals Corporation and Apthera, Inc., its wholly owned subsidiary. The Company has not generated any revenues since inception nor are any revenues expected for the foreseeable future. The Company expects to incur significant operating losses for the foreseeable future while the Company advances its future product candidates from discovery through pre-clinical studies and clinical trials and seek regulatory approval and potential commercialization, even if the Company is collaborating with pharmaceutical and larger biotechnology companies. In addition to these increasing research and development expenses, the Company expects general and administrative costs to increase as the Company recruits additional management and administrative personnel. The Company will need to generate significant revenues to achieve profitability and may never do so. The Company believes that its existing cash and cash equivalents should be sufficient to fund its operations through at least the second quarter of 2012. In the future, the Company will be dependent on obtaining funding from third parties such as proceeds from the sale of equity, funded research and development payments and payments under partnership and collaborative agreements, in order to maintain its operations and meet its obligations to licensors. There is no guarantee that debt, additional equity or other funding will be available to the Company on acceptable terms, or at all. If the Company fails to obtain additional funding when needed, it would be forced to scale back, or terminate, the Company’s operations or to seek to merge with or to be acquired by another company. The accompanying condensed financial statements have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (“SEC”) and should be read in conjunction with the Company’s financial statements and the notes thereto for the year ended December 31, 2010 included in the Company’s Annual Report on Form 10-K filed with the SEC on April 15, 2011. Certain information and footnote disclosures normally included in financial statements prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. The information presented as of and for the six month periods ended June 30, 2011 and 2010 and three months ended June 30, 2011 and 2010, as well as the cumulative financial information for the period from January 1, 2003 (date of inception) through June 30, 2011 is unaudited and has been prepared on the same basis as the audited financial statements and includes all adjustments, consisting of only normal recurring adjustments, necessary for the fair presentation of this information in all material respects. The results of any interim period are not necessarily indicative of the results of operations to be expected for a full fiscal year. There have been no material changes to the Company’s significant accounting policies as disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2010. The Company’s operating results will fluctuate for the foreseeable future. Therefore, period-to-period comparisons should not be relied upon as predictive of the results in future periods. Uses of estimates in preparation of financial statements The preparation of financial statements in accordance with U.S. 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. Derivative Financial Instruments During the normal course of business, from time to time, the Company issues warrants and options to vendors as consideration to perform services. It may also issue warrants as part of a debt or equity financing. The Company does not enter into any derivative contracts for speculative purposes. The Company recognizes all derivatives as assets or liabilities measured at fair value with changes in fair value of derivatives reflected as current period income or loss unless the derivatives qualify for hedge accounting and are accounted for as such. In accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 815-40, “Derivatives and Hedging — Contracts in Entity’s Own Stock”, the value of these warrants is required to be recorded as a liability, as the holders have an option to put the warrants back to the Company in certain events, as defined. Obligations to Repurchase Shares of the Company’s Equity Securities In accordance with FASB ASC Topic 480-10, “Distinguishing Liabilities from Equity”, the Company recognizes all obligations to repurchase shares of its equity securities that require or may require the Company to settle the obligation by transferring assets, as liabilities or assets in some circumstances measured at fair value with changes in fair value reflected as current period income or loss and are accounted for as such. Deferred Revenue Deferred revenue consists of advance payments received under government grants. The Company will recognize revenue when the obligations under the grants are fullfilled.

1. Description of Business and Basis of Presentation

RXi Pharmaceuticals Corporation (NASDAQ: RXII) is a biotechnology company focused on discovering, developing and commercializing innovative therapies addressing major unmet medical needs using targeted biotherapeutics. RXi is pursuing the development of novel cancer therapeutics using peptide-based immunotherapy products, including our main product candidate, NeuVax™ (E75), for the treatment of various cancers.

In this document, “we”, “our”, “ours”, “us”, “RXi”, and the “Company” refer to RXi Pharmaceuticals Corporation and Apthera, Inc., its wholly owned subsidiary. The Company has not generated any revenues since inception nor are any revenues expected for the foreseeable future. The Company expects to incur significant operating losses for the foreseeable future while the Company advances its future product candidates from discovery through pre-clinical studies and clinical trials and seek regulatory approval and potential commercialization, even if the Company is collaborating with pharmaceutical and larger biotechnology companies. In addition to these increasing research and development expenses, the Company expects general and administrative costs to increase as the Company recruits additional management and administrative personnel. The Company will need to generate significant revenues to achieve profitability and may never do so.

The Company believes that its existing cash and cash equivalents should be sufficient to fund its operations through at least the second quarter of 2012. In the future, the Company will be dependent on obtaining funding from third parties such as proceeds from the sale of equity, funded research and development payments and payments under partnership and collaborative agreements, in order to maintain its operations and meet its obligations to licensors. There is no guarantee that debt, additional equity or other funding will be available to the Company on acceptable terms, or at all. If the Company fails to obtain additional funding when needed, it would be forced to scale back, or terminate, the Company’s operations or to seek to merge with or to be acquired by another company.

The accompanying condensed financial statements have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (“SEC”) and should be read in conjunction with the Company’s financial statements and the notes thereto for the year ended December 31, 2010 included in the Company’s Annual Report on Form 10-K filed with the SEC on April 15, 2011. Certain information and footnote disclosures normally included in financial statements prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. The information presented as of and for the six month periods ended June 30, 2011 and 2010 and three months ended June 30, 2011 and 2010, as well as the cumulative financial information for the period from January 1, 2003 (date of inception) through June 30, 2011 is unaudited and has been prepared on the same basis as the audited financial statements and includes all adjustments, consisting of only normal recurring adjustments, necessary for the fair presentation of this information in all material respects. The results of any interim period are not necessarily indicative of the results of operations to be expected for a full fiscal year. There have been no material changes to the Company’s significant accounting policies as disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2010. The Company’s operating results will fluctuate for the foreseeable future. Therefore, period-to-period comparisons should not be relied upon as predictive of the results in future periods.

Uses of estimates in preparation of financial statements

The preparation of financial statements in accordance with U.S. 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.

Derivative Financial Instruments

During the normal course of business, from time to time, the Company issues warrants and options to vendors as consideration to perform services. It may also issue warrants as part of a debt or equity financing. The Company does not enter into any derivative contracts for speculative purposes. The Company recognizes all derivatives as assets or liabilities measured at fair value with changes in fair value of derivatives reflected as current period income or loss unless the derivatives qualify for hedge accounting and are accounted for as such. In accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 815-40, “Derivatives and Hedging — Contracts in Entity’s Own Stock”, the value of these warrants is required to be recorded as a liability, as the holders have an option to put the warrants back to the Company in certain events, as defined.

Obligations to Repurchase Shares of the Company’s Equity Securities

In accordance with FASB ASC Topic 480-10, “Distinguishing Liabilities from Equity”, the Company recognizes all obligations to repurchase shares of its equity securities that require or may require the Company to settle the obligation by transferring assets, as liabilities or assets in some circumstances measured at fair value with changes in fair value reflected as current period income or loss and are accounted for as such.

Deferred Revenue

Deferred revenue consists of advance payments received under government grants. The Company will recognize revenue when the obligations under the grants are fullfilled.