Alnylam Pharmaceuticals this week announced that the US Patent and Trademark Office has upheld certain claims within a company patent covering the use of siRNAs against kinesin spindle protein, the target of the company's phase I liver cancer drug ALN-VSP.
According to Alnylam, the patent, No. 7,718,629, was challenged by Tekmira Pharmaceuticals' subsidiary Protiva Biotherapeutics. Alnylam and Tekmira are currently embroiled in a legal dispute over the rights to siRNA delivery technology (GSN 3/17/2011).
"The maintained claims in the KSP RNAi patent cover the siRNA composition of matter used in ALN-VSP and define the relevant claims for further development and commercialization of this promising RNAi therapeutic for liver cancers," Alnylam CBO Laurence Reid said in a statement.
As part of their dispute, Alnylam has alleged that Tekmira filed a patent application on an siRNA sequence claimed in the '629 patent. The USPTO is now set to review the priority dates for the companies' respective intellectual property, it added.
In a statement, Tekmira President and CEO Mark Murray characterized the USPTO decision as a victory for his company.
"At this stage of the proceedings, the [patent office] denied or deferred all four of Alnylam's motions and granted two of our three motions, including our motion that Alnylam's broad claims are unpatentable due to lack of adequate written description support,” he said.
“Alnylam's corresponding motion that Protiva's claims are unpatentable for lack of written description support was denied, as was their motion that Protiva is not entitled to priority benefit based on our provisional applications,” Murray added. “Moving forward, we believe Tekmira has earlier priority on the remaining claims, which will be determined in the next phase of the interference proceedings.”