RXi Pharmaceuticals Corporation, a clinical-stage RNAi company developing innovative therapeutics that address significant unmet medical needs, announced the results of a consumer/functional testing program with RXI-231, a cosmetic ingredient based on sd-rxRNA® that targets tyrosinase (TYR).

The cosmetic product is a gel formulation designed to aid in the reduction of pigmentation and thereby improving skin appearance. The results from the completed consumer testing program, in combination with previously announced preclinical data on melanin content in cultured melanocytes and 3-dimensional reconstituted human skin models, show that RXI-231 has the potential to reduce skin pigmentation induced by UV exposure in vivo.

Dr. Gerrit Dispersyn, Chief Development Officer at RXi stated, “We are very pleased with these positive results of our consumer testing program with RXI-231. These results not only validate our preclinical data about the effect of RXI-231 on skin pigmentation, but also provide important information on the capabilities of our proprietary topical formulation for the use of our sd-rxRNA based cosmetic ingredients in the consumer care space.” He further added that “In addition, the team is working diligently toward providing updates on our clinical programs before the end of this year, including our hypertrophic scar study, RXI-109-1402.”

Three studies were performed under the consumer testing program. The first two studies in volunteers determined that the RXI-231 gel formulation does not cause irritation and sensitization when applied to the skin.  A third study investigated the potential of RXI-231 to impact a skin melanin content (pigmentation) increase induced by UV exposure, as measured by narrow-band reflectance spectroscopy, in a study design similar to one well documented in peer-reviewed journal articles and used by various cosmetic companies. Specific spectroscopic results – known to correlate well with skin melanin content – show that application with RXI-231 containing gel, as compared to vehicle gel, can reduce a change of skin tone triggered by UV.

RXI-231 targets TYR, a key enzyme involved in the synthesis of melanin.  Initial results with RXI-231 resulted in a visible reduction of pigmentation in 3-dimensional reconstituted human epidermal culture. Further testing showed a decrease in melanin content in cultured primary human melanocytes lasting for at least one week after a single dose.  RXi has developed a gel formulation that allows sd-rxRNA based cosmetic ingredients, which are relatively large (9-12 kDa) and negatively charged, to penetrate into the skin layers where the melanin producing cells reside. The Company completed the manufacture of a batch of RXI-231 containing gel product for this consumer testing study.

About RXi’s Consumer Care Products

RXi’s consumer care products are intended to affect the appearance of the skin. The Company has selected tyrosinase and collagenase as targets for its self-delivering RNAi platform because they are relevant for consumer product development. Two sd-rxRNA based compounds, RXI-231 and RXI-185, are currently in development as cosmetic ingredients to improve the appearance of pigmentation and improve the appearance of wrinkles or skin laxity, respectively.

Both RXI-231 and RXI-185 are part of RXi’s partnering and business growth initiatives providing multiple development opportunities for non-therapeutic skin health.

About RXi Pharmaceuticals

RXi Pharmaceuticals Corporation is a clinical-stage company developing innovative therapeutics that address significant unmet medical needs. Building on the pioneering discovery of RNAi, scientists at RXi have harnessed the naturally occurring RNAi process which can “silence” or down-regulate the expression of a specific gene that may be overexpressed in a disease condition. RXi developed a robust RNAi therapeutic platform including self-delivering RNA (sd-rxRNA) compounds that selectively block the expression of any target in the genome, thus providing applicability to many therapeutic areas. Our current programs include cell-based immunotherapy, dermatology, and ophthalmology. RXi’s extensive patent portfolio provides for multiple product and business development opportunities across a broad spectrum of therapeutic areas and we actively pursue research collaborations, partnering and out-licensing opportunities with academia and pharmaceutical companies. Additional information may be found on the Company’s website, 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: our ability to successfully develop RXI-109, Samcyprone™ and our other product candidates (collectively “our product candidates”); the future success of our clinical trials with our product candidates; the timing for the commencement and completion of clinical trials; our ability to enter into strategic partnerships and the future success of these strategic partnerships; and our ability to deploy our sd-rxRNA® technology through partnerships, as well as the prospects of these partnerships to provide positive returns. Forward-looking statements about expectations and development plans of RXi’s product candidates and partnerships involve significant risks and uncertainties, including the following: risks that we may not be able to successfully develop and commercialize our product candidates; risks that product development and clinical studies may be delayed, not proceed as planned and/or be subject to significant cost over-runs; risks related to the development and commercialization of products by competitors; risks related to our ability to control the timing and terms of collaborations with third parties; and risks that other companies or organizations may assert patent rights preventing us from developing or commercializing our product candidates. Additional risks are detailed in our most recent Annual Report on Form 10-K and subsequent Quarterly Reports on Form 10-Q under the caption “Risk Factors.” Readers are urged to review these risk factors and to not act in reliance on any forward-looking statements, as actual results may differ from those contemplated by our forward-looking statements. RXi does not undertake to update forward-looking statements to reflect a change in its views, events or circumstances that occur after the date of this release.