GLOBE NEWSWIRE -- Tekmira Pharmaceuticals Corporation, a leading developer of RNA interference (RNAi) therapeutics, announced today that the United States Patent & Trademark Office (USPTO) and the European Patent Office (EPO) have issued key patents covering elements of Tekmira's leading lipid nanoparticle (LNP) technology, which is used to deliver nucleic acid therapeutics, including small interfering RNA (siRNA).