SLN.L Regulatory News (SLN)

15 Aug 2007 15:25

Silence Therapeutics plc

Disclosure of Information required by AIM rule 26

London 15 August 2007 - Silence Therapeutics plc (the Company) announces that with effect from today the information required by rule 26 of the AIM Rules for Companies (February 2007) is available on the Investor page of the Company's website - www.silence-therapeutics.com .

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Notes to Editors

Silence Therapeutics plc (www.silence-therapeutics.com)

Silence Therapeutics plc is a leading RNAi company. RNA interference (RNAi) can selectively "silence" genes linked to the onset of disease.

Silence Therapeutics has developed novel, proprietary short interfering RNA ("siRNA") molecules, AtuRNAi, which provide a number of advantages over conventional siRNA molecules as they show increased stability against nuclease degradation. In addition, the Company has developed a proprietary systemic delivery system, AtuPLEX. This enables the delivery of siRNA molecules to targeted diseased tissues and cells, whilst increasing their bioavailability and intracellular uptake.

In July 2007, Silence Therapeutics formed a research and development collaboration with Astra Zeneca to develop AtuRNAi against five targets in respiratory indications. The Group's AtuRNAi technology has also been sublicensed to Pfizer by Quark Pharmaceuticals, through Quark's license of the compound RTP-801i-14 for the treatment of Age-related Macular Degeneration (AMD) and a number of other indications. This compound entered the clinic in early 2007. Silence Therapeutics has licensed a further AtuRNAi compound, AKIi-5, to Quark Biotech Inc. This compound has been granted an IND for acute kidney injury and is expected to enter the clinic in 2007. In addition, Silence Therapeutics expects to begin the clinical development of its proprietary AtuRNAi therapeutic molecules for systemic cancer indications, such as gastrointestinal and non-small lung cancer, in 2008.

Silence Therapeutics is based in London, UK, and Berlin, Germany, and is listed on AIM.

About RNAi

RNA interference (RNAi), a Nobel Prize winning technology, is one of the most exciting areas of drug discovery today. It represents a completely new approach to selectively "silence" or inactivate disease relevant genes and as such it has the potential to create a new class of therapeutic products. RNAi could therefore offer a therapeutic approach to a broad range of diseases (cancer, infectious diseases, inherited diseases), many of which have been regarded as incurable and are not addressed by current therapeutics, therefore providing a large market opportunity.

Forward-Looking Statements

This press release includes forward-looking statements that are subject to risks, uncertainties and other factors. These risks and uncertainties could cause actual results to differ materially from those referred to in the forward-looking statements. All forward-looking statements are based on information currently available to Silence Therapeutics and Silence Therapeutics assumes no obligation to update any such forward-looking statements.

Enquiries:

For further information, please contact the following:

Silence Therapeutics plc Investor Relations +44(0)20 7307 1620 Citigate Dewe Rogerson Iain Ross, Chairman +44(0)20 7638 9571

Jeff Vick, Chief Executive Officer David Dible Melvyn Davies, Finance Director Yvonne Alexander +49(0)30 9489 2800 Nominated Adviser Thomas Christĩly, Chief Operating Officer Grant Thornton Corporate Finance Dr. Klaus Giese, Chief Scientific Officer +44 (0) 20 7383 5100 Gerry Beaney Colin Aaronson