SCOTTSDALE, AZ--(Marketwire - 03/31/11) - Apthera, Inc., a privately-held biotechnology company developing a pipeline of peptide based immune-therapies, announced today it has entered into a definitive merger agreement with RXi Pharmaceuticals Corporation (NASDAQ:RXII - News) under which RXi will acquire Apthera.Under the terms of the agreement, Apthera shareholders will initially receive approximately 4.8 million shares of RXi's common stock. Apthera's stockholders will also be entitled to contingent payments based on the achievement of certain development and commercial milestones relating to Apthera's NeuVax™ product candidate.Dr. Mark Schwartz, President and CEO of Apthera, will join RXi as Executive Vice President and Chief Operating Officer. Dr. Mark Ahn, currently a director of RXi, will be the President and Chief Executive Officer."This merger will provide significant experience and support for moving our late stage HER2 direct breast cancer drug, NeuVax™ into phase III in the first half of 2012," commented Dr. Mark Schwartz, President and CEO of Apthera. "This is a key milestone for the company, and we look forward to accelerating our work on this exciting late stage development program.""I believe RXi is a merger partner with the skills, resources and enthusiasm necessary to bring our late stage product NeuVax™ forward," commented Ira Leiderman, Chairman of Apthera. "This transaction is a key milestone in this exciting program targeting a major unmet medical need."NeuVax™, a peptide-based immunotherapy for low-to-intermediate HER2+ breast cancer patients not eligible for Herceptin®, is expected to enter Phase III clinical trials in the first half of 2012 under an FDA approved Special Protocol Assessment (SPA).About Apthera, Inc.Apthera, Inc. ("The Company") is a private biotechnology company founded in July 2005 to develop and commercialize a pipeline of peptide-based immunotherapies for the adjuvant treatment of HER2-positive cancers. Currently, the Company has products in clinical trials, all of which are aimed at reducing disease recurrence rates for breast and prostate cancers. For more information, visit www.apthera.com.About RXi Pharmaceuticals CorporationRXi Pharmaceuticals is a recognized leader in RNAi-based therapeutic discovery and development with a comprehensive therapeutic platform that includes both RNA interference (RNAi) compounds and delivery methods. The company is leveraging this broad and integrated RNAi therapeutic platform to build a pipeline of RNAi therapeutics for the treatment of a number of disease areas, including its core focus of developing treatments for anti-scarring and retinal disorders as well as a continued interest in oncology and indications accessible by spinal cord delivery. RXi Pharmaceuticals believes it is well positioned to compete successfully in the RNAi therapeutics market based on the strength of its next generation therapeutic platform, experienced management team, accomplished Scientific Advisory Board, including Nobel Laureate, Dr. Craig Mello, and its broad intellectual property position in RNAi chemistry and delivery. www.rxipharma.comForward-Looking StatementsThis press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, statements about the timing and completion of the Apthera merger, future expectations, plan and future development of RXi Pharmaceutical Corporation's and Apthera's products and technologies. These forward-looking statements about future expectations, plans and prospects of the development of RXi Pharmaceutical Corporation's and Apthera's products and technologies involve significant risks, uncertainties and assumptions, including the risk that the development of NeuVax or our RNAi-based therapeutics may be delayed or may not proceed as planned and we may not be able to complete development of any RNAi-based product, the risk that the FDA approval process may be delayed for any drugs that we develop, risks related to development and commercialization of products by our competitors, risks related to our ability to control the timing and terms of collaborations with third parties and the possibility that other companies or organizations may assert patent rights that prevent us from developing our products. Actual results may differ materially from those RXi Pharmaceuticals Corporation contemplated by these forward-looking statements. RXi Pharmaceuticals Corporation does not undertake to update any of these forward-looking statements to reflect a change in its views or events or circumstances that occur after the date of this release.