RXi Pharmaceuticals Corporation, a clinical-stage RNAi company developing innovative therapeutics in dermatology and ophthalmology that address significant unmet medical needs, has received an issue notification from the United States Patent and Trademark Office (USPTO) for a patent covering methods for the treatment of compromised skin with self-delivering RNAi (sd-rxRNAs) compounds targeting connective tissue growth factor (CTGF), including RXI-109, to prevent, reduce or inhibit dermal scarring.  US Patent #9,303,259, is scheduled to expire in 2029.

"This issue notification from the USPTO further strengthens RXi's Intellectual Property position in the area of dermal scarring," said Dr Geert Cauwenbergh, president and CEO of RXi Pharmaceuticals. He added that, "From our ongoing phase 2 clinical trial, we have already reported preliminary results indicating that the use of RXI-109 after scar revision surgery had a visible, beneficial effect on the suppression of hypertrophic scarring, at three months following revision surgery.  This patent enhances our ability to broadly protect our proprietary technology, including our anti-fibrotic compounds for the treatment of dermal scarring, reinforcing the potential for future commercial and business development opportunities."

About RXI-109: Proprietary Self-delivering RNAi (sd-rxRNA) Compound with Built-In Drug-Like Properties

Building on the pioneering work of Dr Craig Mello, Nobel Laureate and RXi's Scientific Advisory Board Chairman, scientists at RXi developed novel sd-rxRNA compounds where drug-like properties are built into the RNAi compound itself. These proprietary compounds are novel RNAi compounds with enhanced properties for therapeutic use including:  efficient spontaneous cellular uptake, stability, reduced potential for immune stimulation, and potent, long-lasting intracellular activity.  All cell types tested (primary, neuronal and non-adherent) internalize sd-rxRNA compounds uniformly and efficiently, resulting in potent and long lasting silencing.  Efficient cellular uptake is observed both in vitro and in vivo, as well as in tissues including skin, retina, lung, spinal cord and liver.

RXI-109, an sd-rxRNA compound, silences connective tissue growth factor (CTGF), which plays a key role in tissue regeneration and repair.  RXI-109 is currently in development to reduce or inhibit scar formation in the skin and in the eye.  A Phase 1/2 clinical study, RXI-109-1501, is underway to evaluate the safety and clinical activity of RXI-109 to prevent the progression of retinal scarring, a harmful component of numerous retinal diseases. In addition, a Phase 2 clinical trial, RXI-109-1402, is currently evaluating RXI-109 as a treatment to reduce the recurrence of hypertrophic scars following scar revision surgery.  Over 100 subjects have been treated with RXI-109 by intradermal injection in all trials to date. Multiple intradermal injections were well tolerated at all dose levels.  RXI-109 was shown to cause a dose-dependent silencing of CTGF messenger RNA and protein levels in the treated areas of the skin compared to placebo and preliminary results from Phase 2a studies indicate a clinical effect on scar appearance.