RXi Pharmaceuticals Announces Positive Results in its First Double Blind Study in Healthy Volunteers with RXI-109

RXI-109 was well tolerated and produced a statistically significant and dose dependent reduction of Connective Tissue Growth Factor (CTGF), a protein that causes abnormal scarring when it is over-expressed in a wound

Jun 06, 2013, 07:02 ET from RXi Pharmaceuticals Corporation

WESTBOROUGH, Mass., June 6, 2013 /PRNewswire/ -- RXi Pharmaceuticals Corporation (OTCQB: RXII), a biotechnology company focused on discovering, developing and commercializing innovative therapies addressing major unmet medical needs using RNA-targeted technologies, today  announced the unblinded results of the first of their 2 placebo-controlled double blind studies in volunteers with their anti-scarring agent RXI-109, a proprietary sd-rxRNA® compound that has been shown in vitro and in animals to reduce mRNA for connective tissue growth factor (CTGF). Over-expression of this protein in wounds has been associated with abnormal scarring as seen in hypertrophic scars and keloids.

"Based on the animal data, we were confident that RXI-109 would not cause significant side effects or toxicities in this first study, and we are pleased to announce that confirmation today," said Dr. Geert Cauwenbergh, President and CEO of RXi Pharmaceuticals. He added that: "It is remarkable and a great outcome that we have also been able to get a good read-out on a key biomarker for scarring in this study. Indeed, almost 3 months after a single intradermal dose of RXI-109, histological comparisons between the drug- and placebo-treated sites in the volunteers showed that RXI-109 significantly reduced the expression of CTGF in the wound area in a dose dependent manner, suggesting a potent and long lasting effect on this key biomarker for abnormal scarring. We look forward to having the unblinded results of our second Phase 1 trial, with multiple doses of RXI-109, available for our Investor and Analyst Symposium  on July 12, 2013."

About the study

In this first Phase 1 study, 15 volunteers with no known predisposition for abnormal scarring were treated in 5 cohorts. Each subject received a single intradermal injection of RXI-109 in two small 2-cm areas of the abdomen. Two identical areas on the other side of the abdomen were treated with placebo injections.  The next day, 24 hours after treatment, these 4 areas received an incision that was immediately closed again. RXI-109 was given in dose ascending manner to 5 cohorts, with doses ranging from 0.5 mg/cm to 5 mg/cm (or total doses of RXI-109 per volunteer from 2 to 20 mg). Subjects were followed intensively for side effects, safety and toxicity in the 7 days post injection, and regularly afterwards for up to 3 months, at which point they received an abdominoplasty.  Samples were collected from the portion of the skin that was removed during the surgery for histological and biomarker assessments on scar area and CTGF. Various parameters were monitored for systemic side effects: ECG, blood biochemistry, blood count, urinalysis, assessments of the incisions by physician and subjects and measurement of RXI-109 into the systemic circulation after intradermal injection. No significant side effects or toxicity were observed and the incisions did not appear to slow healing on the active or the placebo side, indicating that RXI-109 does not delay wound closure. In addition, blood level measurements for RXI-109 indicated that the maximum systemic exposure was only about 5% of the intradermally administered dose. The histological evaluation at 3 months after the single intradermal injection showed that the average wound area for all sites (30 sites treated with RXI-109 and 30 sites treated with placebo) was not different between both treatment arms (p = 0.22), confirming no negative effect on wound healing for the drug.  Interestingly, there was a statistically significant reduction in the average CTGF protein concentration in the RXI-109 treated sites compared to placebo treated sites (p = 0.02). In addition the highest reduction in CTGF protein levels in the incision areas was observed in the 2 highest dosed treatment cohorts. The noted effect on CTGF protein level is remarkable given the 3 month time period between the single injection and the skin tissue harvesting.

It is concluded from this study that an intradermal injection of RXI-109 is well tolerated, devoid of systemic toxic effects and results in minimal uptake in the systemic circulation. In addition the study shows no negative effects on the wound healing process in individuals with a normal wound healing pattern. Moreover, the observed effect of RXI-109 on the reduction of CTGF protein in the incision area 3 months after a single intradermal injection of RXI-109, as compared to placebo, suggests that the compound has a long lasting effect on silencing this protein, with the highest treatment doses having a more pronounced effect than the lower doses.

About RXi Pharmaceuticals Corporation

RXi Pharmaceuticals Corporation (OTCQB: RXII) is a biotechnology company focused on discovering, developing and commercializing innovative therapies based on its proprietary, self-delivering RNAi platform. Therapeutics that use RNA interference, or "RNAi," have great  promise because of their ability to down-regulate, the expression of a specific gene that may be over-expressed in a disease condition. Building on the pioneering work of scientific founder and Nobel Laureate Dr. Craig Mello, a member of the RXi Scientific Advisory Board, RXi's first RNAi product candidate, RXI-109, targets connective tissue growth factor (CTGF) to reduce dermal scarring (fibrosis), entered into human clinical trials in June 2012.  For more information, please visit 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, planned and future development of RXi Pharmaceuticals Corporation's products and technologies. Forward-looking statements about expectations and development plans of RXi's products involve significant risks, and uncertainties: risks that RXi may not be able to successfully develop its candidates, or that development of RNAi-based therapeutics may be delayed or not proceed as planned, or that we may not develop any RNAi-based product; risks that the development process for our product candidates may be delayed, risks related to development and commercialization of products by our competitors, risks related to our ability to control timing and terms of collaborations with third parties, and the possibility that other companies or organizations may assert patent rights preventing us from developing our products. Actual results may differ from those contemplated by these 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.

RXi Pharmaceuticals Corporation
Tamara McGrillen, 508-929-3646

SOURCE RXi Pharmaceuticals Corporation