IP update

IP Update

10 July 2017

Silence Therapeutics plc, AIM:SLN ("Silence" or "the Company") a leader in the discovery, delivery, and development of novel RNA therapeutics for the treatment of serious diseases with unmet medical need, notes Alnylam Pharmaceutical's press release of July 7, 2017 which stated that "Alnylam and Sanofi Genzyme Initiate ATLAS Phase 3 Program with Investigational RNAi Therapeutic Fitusiran in Patients with Hemophilia A and B with or without Inhibitors ".

On July 3, 2017, Silence referenced Fitusiran within a list of Alnylam products that are being included within a claim issued in the UK courts relating to Silence's entitlement to supplementary protection certificates (SPC's) that extend European patent protection on those products.

Silence further notes that on November 14, 2016, Alnylam also announced that "Sanofi Genzyme elected to opt in to co-develop (through Sanofi R&D) and co-commercialize Fitusiran, an investigational RNAi therapeutic for the treatment of hemophilia and rare bleeding disorders (RBD), in the United States, Canada and Western Europe." This co-development includes a $25 million milestone payable by Sanofi Genzyme upon the initiation of the first global Phase 3 clinical trial for Fitusiran as well as further payments totalling up to $75 million upon the achievement of development and regulatory milestones for Fitusiran.

Ali Mortazavi, Chief Executive Officer of Silence Therapeutics, commented:

"We are delighted on behalf of patients with hemophilia A and B to hear this encouraging development, further highlighting the importance of siRNA medicines, and reiterate as stated in our press release on 30 May, 2017, that we consider potential licences under our patent estate could have a significant financial effect relative to the current market capitalisation of Silence."

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About Silence Therapeutics plc

Silence Therapeutics develops a new generation of medicines by harnessing the body's natural mechanism of RNA interference, or RNAi, within its cells. Our proprietary technology can selectively inhibit any gene in the genome, specifically silencing the production of disease-causing proteins. Using our enabling delivery systems, we have achieved an additional level of specificity by delivering our therapeutic RNA molecules exclusively to target cells. Silence's proprietary RNA chemistries and delivery systems are designed to improve the stability of our molecules and enhance effective delivery to target cells, providing a powerful modular technology well suited to tackle life-threatening diseases.