RXi Pharmaceuticals Presents New Preclinical RNAi Data at the Keystone Mechanism and Biology of Silencing Conference

WORCESTER, Mass.--(BUSINESS WIRE)--RXi Pharmaceuticals Corporation (Nasdaq: RXII), a recognized leader in RNA interference (RNAi) based therapeutic discovery and development, today announced that new preclinical data using proprietary self-delivering RNAi (sd-rxRNA™) compounds, including RXI-109, will be presented at the Keystone Symposia’s Mechanism and Biology of Silencing conference being held March 20-25, 2011 in Monterey, California.

“RXi has made significant scientific progress and the data to be presented at this conference will highlight important advancements in our technology, platform and therapeutic programs. We have developed a novel class of self-delivering RNAi compounds with improved drug-like properties that may enable the development of therapeutics for a wide range of indications, including our lead development candidate, RXI-109, for the reduction of dermal scarring,“ said Anastasia Khvorova, Ph.D., RXi’s Chief Scientific Officer.

The data will be presented in three posters and one speaker presentation, and will be available on RXi’s website following the conference, www.rxipharma.com/scientific_publications_presentations.html.

• Speaker Presentation – Karen Bulock, Ph.D., Associate Director of Discovery at RXi Pharmaceuticals, will present preclinical in vivo data showing robust, dose dependent, long-lasting, target-specific silencing data with an sd-rxRNA compound targeting CTGF (connective tissue growth factor). Additional data demonstrating that CTGF silencing results in reduction of myofibroblasts and collagen deposition, downstream effects related to abrogation of scar formation, will also be presented.
• Poster: Development of an sd-rxRNA™ Based Therapy for Treatment of Fibrosis: Preclinical Development Abstract - Outlines the results of several sd-rxRNA compounds targeting CTGF for the reduction of dermal scarring. Preclinical results using intradermal injection of CTGF targeting sd-rxRNAs show strong silencing for more than a week, as well as downstream effects related to abrogation of scar formation. RXi has initiated a preclinical development program for RXI-109, an sd-rxRNA compound designed to reduce the expression of CTGF, with a goal of submitting an IND in the second half of 2011.
• Poster: Self-Delivering RNAi Compounds (sd-rxRNA™) Demonstrate Robust Efficacy in vitro and in vivo in the Eye – Describes the preclinical studies used to establish the general utility of sd-rxRNA as a potential treatment for ocular disease. Data from these studies show that sd-rxRNA compounds not only successfully distribute to retinal cells without a delivery vehicle after an intravitreal injection, but also maintain statistically significant silencing of the mRNA target for up to 21 days. In addition, a pilot safety evaluation in mouse reveals no overt morphological, functional or microscopic signs of ocular toxicity.
• Poster: A Novel Class of Self-Delivering RNAi Compounds (sd-rxRNA™) with Robust in vitro and in vivo Efficacy: Mechanism of Action – Describes the development of a novel class of “self-delivering” RNAi (sd-rxRNA) compounds which demonstrate robust cellular uptake and silencing of target genes without the requirement for a delivery vehicle. sd-rxRNAs combine features of conventional RNAi and antisense technology and are heavily chemically modified to improve stability and lipophilicity. Preclinical data demonstrating the mechanism of uptake as well as efficacy of sd-rxRNA compounds using local and systemic administration in vivo will be presented.

About RXi Pharmaceuticals Corporation

RXi Pharmaceuticals is a recognized leader in RNAi-based therapeutics with a comprehensive platform that includes both RNA interference (RNAi) compounds and delivery technologies. The company is leveraging this broad and integrated platform to build a pipeline of RNAi therapeutic candidates for the treatment of a number of disease areas, including its core focus of developing treatments for dermal 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 RNAi 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.com

Forward-Looking Statements

This 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 future expectations, plans and future development of RXi Pharmaceutical Corporation’s products, technologies and partnering efforts. These forward-looking statements about future expectations, plans and prospects of the development of RXi Pharmaceutical Corporation’s products and technologies and corporate partnerships involve significant risks, uncertainties and assumptions, including the risk that RXi and third parties may not be able to successfully develop technologies that are the subject of collaborations with such third parties, the risk that the development of our RNAi-based therapeutics may be delayed or may not proceed as planned, may not be safe and that 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.