Alnylam Pharmaceuticals Inc., a leading RNAi therapeutics company, has retained key claims for Kinesin Spindle Protein (KSP) RNAi patent (US Patent No. 7,718,629) in interference proceedings from the United States Patent and Trademark Office (USPTO).

The interference was declared on February 28, 2011, between Alnylam’s patent and a patent application (US Patent Application No. 11/807,872) filed by Protiva Biotherapeutics Inc., a subsidiary of Tekmira Pharmaceuticals Corporation, which included a pending claim to an siRNA sequence that was identical to one described in the earlier filed Alnylam patent.

The next phase of the interference proceedings will examine the respective priority date for each of the parties’ claims consistent with current US patent law’s “first to invent” statute.

“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,” said Laurence Reid, senior vice president and chief business officer of Alnylam. “We look forward to the start of the priority phase in these proceedings and believe that our patent will prevail at this stage of the interference.”

The KSP RNAi patent claims the siRNA sequence used in Alnylam’s ALN-VSP investigational drug product, which has completed a phase I clinical study and which the company intends to partner prior to initiation of phase II trials. In addition to the KSP RNAi patent, Alnylam has additional issued patents that specifically cover siRNA sequences in the ALN-VSP drug product (US Patent Nos. 7,947,659 and 7,919,473), and other patents pending. Further, the company maintains an exclusive position on a broad intellectual property estate covering RNAi therapeutics including fundamental patents covering siRNA architecture, chemistry patents covering siRNA modifications, and delivery patents covering conjugates and lipid nanoparticles (LNP), including the Semple and Wheeler LNP patent families that broadly cover the formulation used in ALN-VSP.

RNAi (RNA interference) is a revolution in biology, representing a breakthrough in understanding how genes are turned on and off in cells, and a completely new approach to drug discovery and development. Its discovery has been heralded as “a major scientific breakthrough that happens once every decade or so,” and represents one of the most promising and rapidly advancing frontiers in biology and drug discovery today which was awarded the 2006 Nobel Prize for Physiology or Medicine.

RNAi is a natural process of gene silencing that occurs in organisms ranging from plants to mammals. By harnessing the natural biological process of RNAi occurring in our cells, the creation of a major new class of medicines, known as RNAi therapeutics, is on the horizon. Small interfering RNAs (siRNAs), the molecules that mediate RNAi and comprise Alnylam’s RNAi therapeutic platform, target the cause of diseases by potently silencing specific mRNAs, thereby preventing disease-causing proteins from being made. RNAi therapeutics have the potential to treat disease and help patients in a fundamentally new way.

Alnylam is developing novel therapeutics based on RNA interference, or RNAi.