Alnylam Pharmaceuticals, Inc, a leading RNAi therapeutics company, announced that the United States Patent and Trademark Office (USPTO) has issued a new patent (US patent no. 8,618,277, or "'277 patent") in the company's McSwiggen patent estate.

The McSwiggen patent estate broadly describes chemical modifications of RNAi therapeutics needed to achieve "drug-like" properties in siRNA, the molecules that mediate RNAi. Specifically, the '277 patent includes claims that the company believes are critical for the development of RNAi therapeutics for the treatment of hepatitis B virus (HBV) infection. This patent is held exclusively by Alnylam and is not licensed to any third parties. The McSwiggen patent estate comprises a core component of Alnylam's overall intellectual property (IP) estate for the advancement of RNAi therapeutics, and was recently obtained through the company's acquisition of Sirna Therapeutics from Merck.

"We are pleased with the USPTO's decision to issue the '277 patent from our McSwiggen patent family, a key component of the IP estate we recently obtained through our acquisition of Sirna Therapeutics from Merck. Our '277 patent has broad, sequence-independent claims on chemically modified siRNAs which we believe are critical for the development and commercialisation of RNAi therapeutics for the treatment of HBV infection," said Laurence Reid, Ph.D., senior vice president and chief business officer of Alnylam. "Our IP estate remains a cornerstone in our efforts to advance RNAi therapeutics to patients in need. In the case of the '277 patent, we intend to maximise the value of this newly issued IP solely through the advancement of ALN-HBV our GalNAc-conjugated siRNA targeting the HBV genome for the treatment of HBV infection where we expect to select our Development Candidate by this year's end and to file an investigational new drug application at or around year-end 2015."

The McSwiggen patent family includes 23 granted patents around the world, including patents in the U.S.1 and the EU2, and generally describes chemical modifications of siRNA. The '277 patent includes broad, sequence-independent issued claims on compositions of chemically modified siRNA targeting HBV, including:

siRNA that mediates RNAi against a hepatitis B virus target mRNA wherein each strand is between 18 to 24 nucleotides; and sense and antisense strand each comprising 10 or more 2'-deoxy, 2-O-Me, 2'-F or universal base modified nucleotides and 10 or more pyrimidines of the sense and/or antisense strand are 2'-deoxy, 2-O-Me, 2'-F.

Such chemical modifications of siRNA are generally required to achieve in vivo potency and durability for RNAi therapeutics. Additional HBV-directed claims for the McSwiggen patent family are pending in filed patent applications.

Granted claims of the '277 patent, as well as other granted Alnylam owned or licensed patents, are provided on the company's website, and in aggregate broadly cover siRNA and their use in a wide range of lengths from 15 to 49 nucleotides, and chemical modifications with naturally or non-naturally occurring nucleotides, including, for example acyclic nucleotides such as those termed "unlocked nucleobase analogs." In addition, Alnylam's owned or licensed patents broadly cover delivery of RNAi therapeutics, including those that employ GalNAc-siRNA conjugate technology. Finally, Alnylam's IP estate also includes patents that broadly cover siRNA toward a wide range of disease targets.

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 RNA (siRNA), 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.