SLN.L Regulatory News (SLN)

Silence Therapeutics plc ("Silence" or the "Company")

Business Update

ATU027

Silence Therapeutics is delighted to report it has received formal approval from the German authorities (BfArM) for its phase 1b/2a combination trial into pancreatic cancer. The trial will test Silence's Atu027 anti-metastatic compound in combination with Gemcitabine, the leading anti-tumour drug. It is expected that the 1b element of the trial will last for 3 months and the 2a element scheduled to begin in July 2013 and ending approximately in July 2014.

 BfArM has also encouraged Silence, primarily due to the exceptional safety profile of ATU027 in phase 1, to apply for 1b/2a trials using Atu-027 as a combination therapy across a wide range of cancers. It indicated that these further trials could be run broadly in parallel with pancreatic cancer. ATU027 is now the most advanced RNAi Oncology program in the world and has a novel anti-metastatic effect which results in preventing extravasation and intravasation of cancer cells. This is in contrast to conventional cancer drugs which target the primary tumour and are non-specific for metastasis.

Other Indications

Separately, Silence is delighted to report excellent results from proof of concept studies in acute liver injury. The work was carried out at the University of Rostock under Professor Brigitte Vollmar. Crucially the studies showed that Silence's new lipid formulation, DBTC, is effective at delivering RNAi treatments to liver tissues. On the basis of this success as well as other results, Silence is moving ahead with plans to target non oncology indications including orphan and rare diseases.

Business Update

The company is of the belief that RNAi based therapeutics are on the cusp of a new wave of drug development, better delivery platforms and capital investment. This has been borne out by recent clinical trials as well as significant public and private equity deals.

Silence Therapeutics is the only company worldwide who can effectively deliver siRNAs to multiple locations in the human body. Together with the strong patent position in its' synthetic siRNA, AtuRNAi, Silence Therapeutics is amongst a handful of companies who have the freedom to operate in this space.

As a result of the above factors, the company is actively looking at an aggressive expansion of its platform, drug targets and key personnel. The company and its major shareholders are reviewing the financing options in respect of this expansion.

Current cash stands at c. £8.0m.

Silence Therapeutics

Ali Mortazavi, director of corporate strategy +44 (0)7768 694739

a.mortazavi@silence-therapeutics.com

Tim Freeborn, finance director +44 (0)20 7491 6520

 t.freeborn@silence-therapeutics.com

N+1 Singer

Shaun Dobson/Jenny Wyllie

+44 (0)207 4963000

shaun.dobson@n1singer.com

jenny.wyllie@n1singer.com