MARLBOROUGH, Mass. - RXi Pharmaceuticals Corporation today announced that it has been granted a patent by the United States Patent and Trademark Office (USPTO) for the delivery of double stranded siRNAs (21 to 23 nucleotides in length) across the blood-retina barrier (e.g. topical or systemic delivery) for the treatment of wet age-related macular degeneration or diabetic retinopathy. The patent, part of RXi's acquired OPKO estate, is scheduled to expire in 2023.

"This patent, in combination with our issued sd-rxRNA® patents, expands the scope of our intellectual property position in the area of Ophthalmology," said Dr. Geert Cauwenbergh, President and CEO of RXi Pharmaceuticals. He added that, "Not only does this further contribute to the potential commercial and business development opportunities in the future, it is another step towards achieving our long term goals for the acquired OPKO patent estate. Moreover, it further demonstrates our firm commitment to the development of our core technology platform as the key builder of our corporate value".

RXi's intellectual property estate includes patents and patent applications related to chemistries, sequences, configurations, compounds, delivery technologies, and therapeutic targets. We believe these patents and patent applications define broad coverage for the development and commercialization of advanced RNAi therapeutics. In particular, they relate to novel and proprietary structural and chemical modifications patterns, used to introduce "drug-like" properties to rxRNA® compounds. Fundamental IP related to development of RXi's rxRNA compounds covers distinct structures with duplex length shorter than 15 bases, or longer than 25 bases in the context of advanced and diverse chemical modifications patterns. In 2013, RXi acquired the OPKO RNAi intellectual property estate. The OPKO RNAi estate includes 12 patent families and provides broad patent filings for siRNA compounds which target genes involved in angiogenesis, cancer, immune disorders and inflammatory diseases. Methods for siRNA delivery across the blood-brain and blood-retina barrier are also covered for therapeutic and diagnostic use. 

RXi Pharmaceuticals Corporation is a biotechnology company focused on discovering, developing and commercializing innovative therapies based on its proprietary, self-delivering RNAi (sd-rxRNA®) platform.