EPO grants new patent to Silence Therapeutics’ RNAi structural modification technology

Oct 20 2010

Silence Therapeutics plc (AIM: SLN) ("Silence" or the "Company") announces that the European Patent Office (EPO) has granted a new patent that provides broad protection on novel aspects of the RNAi structural modification technology known as the "Zamore Design Rules."  European patent number 1 633 890 titled "Methods and Compositions for Enhancing the Efficacy and Specificity of RNAi" was published today in the European Patent Bulletin.  The European patent covers various breakthrough structural modification methods and compositions which Silence believes are fundamental for the development and commercialization of RNAi therapeutics with enhanced efficacy.

"The granting of this comprehensive patent in Europe is a significant milestone for Silence in our ongoing effort to build one of the world's leading RNAi intellectual property positions.  We have consistently built a strong IP estate around the Zamore technology in the U.S. and have now extended our global coverage to Europe with the granting of this critical patent," stated Philip Haworth, Ph.D., chief executive officer of Silence Therapeutics.  "We have often stated our belief that the 'Zamore Design Rules' represent significant IP to enable the process of bringing effective RNAi therapeutics to market.  With this latest patent grant from the EPO, we are excited to be able to offer potential collaborators or licensing partners access to this strongly protected Zamore technology in both the U.S. and Europe."

The issued patent's method and composition claims include:

• Methods of enhancing the ability of an antisense strand of an RNAi agent to act as a guide strand
• RNAi or siRNA agents for enhancing silencing of a target mRNA in a subject
• Compositions for siRNA duplexes include pre-miRNA and shRNA and vectors to perform the methods described herein

Silence owns exclusive licenses to the "Zamore Design Rule" patent families in the human healthcare field from the University of Massachusetts Medical School.  These patent families disclose various efficacy-enhancing methods and structural elements for RNAi therapeutics, informally known as the "Zamore Design Rules" and are based on the seminal research of Phillip D. Zamore, Ph.D. at the University of Massachusetts Medical School.  Dr. Zamore is a Howard Hughes Medical Institute Investigator, the Gretchen Stone Cook Chair of Biomedical Sciences, and Professor of Biochemistry & Molecular Pharmacology at University of Massachusetts Medical School.  He also serves as co-director of the RNA Therapeutics Institute at the University of Massachusetts Medical School.  Silence expects additional patent issuances related to the Zamore portfolio.  

Silence Therapeutics is executing a proactive strategy to continue to build and strengthen a diverse and competitive intellectual property portfolio that provides the Company and its partners with a strong proprietary position in the RNAi therapeutics space.  The Company believes that it will continue to make significant progress in these efforts as it expects a number of additional valuable RNAi patents to be issued in both the United States and Europe.  At present, Silence's global patent portfolio contains issued patents and pending applications covering strategic areas of RNAi therapeutic development including multiple proprietary siRNA delivery technologies, potent siRNA sequences specific for high-value disease targets and key RNAi sequence and chemical modifications.

SOURCE Silence Therapeutics plc