Inex Pharmaceuticals Corporation and Alnylam Pharmaceuticals Inc. announced that the US Patent and Trademark Office (USPTO) has allowed claims in a patent application that covers nucleic acid-lipid compositions, including cationic liposomes, a family of specialized lipid molecules.
Cationic liposomes enable the delivery of oligonucleotides, including small interfering RNAs (siRNAs), the molecules that mediate RNAi. The US PTO issued a "Notice of Allowance" for patent application 09/431,594, which is derived from the "Wheeler" patent series and includes a number of patents licensed exclusively to Inex through agreements with the University of British Columbia, and which Inex has exclusively licensed to Alnylam for RNAi therapeutics. Following a "Notice of Allowance," the companies would expect final issuance of the patent within six months.
Cationic liposomes have been used as formulations to achieve systemic delivery of RNAi therapeutics in animal models including non-human primates. The newly allowed Wheeler patent covers cationic liposome compositions that contain oligonucleotides, including double-stranded RNAs such as siRNAs. In addition to the newly allowed patent, Inex and Alnylam have exclusive access to additional issued patents for delivery of oligonucleotides with cationic liposomes, including certain issued patents in the Wheeler patent series and "Semple" patent series.
"Our broad and significant collaboration with Alnylam formed just this past January unites Inex's leadership in liposomal delivery technology with Alnylam's leadership in RNAi therapeutics," said Timothy M Ruane, president and CEO of Inex. "The strength of Inex's intellectual property was an important strategic component for this collaboration, and we're gratified that the US PTO continues to recognize the Wheeler patent series for delivery of oligonucleotide therapeutics, including double-stranded RNAs such as siRNAs."
"In a number of published reports from Alnylam and several other groups, systemic delivery of RNAi therapeutics has advanced significantly over the last few years with the use of liposome technology. Accordingly, we have focused on extending our leading intellectual property position in RNAi therapeutics by accessing needed patents covering certain delivery formulations," said Robert Millman, PhD, chief intellectual property counsel for Alnylam. "Given both the newly allowed claims and previously issued patents, we believe that the Wheeler and Semple patent series represent the broadest intellectual property estate covering lipid-based delivery technologies for RNAi therapeutics."