SLN.L Regulatory News (SLN)

4 Dec 2008 07:00

Silence Therapeutics to make regulatory filing to take lead cancer therapy Atu027 into the clinic Confirms progress on third-party discussions

London - December 4th 2008 - Silence Therapeutics plc (AIM: SLN), the leading European biopharmaceutical company focused on RNA interference, is pleased to announce today that it intends to submit a Clinical Trial Application (CTA) for Atu027, its lead drug candidate, before the end of this month.

This week's decision to submit a CTA follows a Board review of progress with Atu027 and, in particular, consideration of recent discussions with BfArM, the German regulator for drugs and medical devices. Atu027 is a small interfering RNA (siRNA) molecule that is being developed for the systemic treatment of cancer.

Silence anticipates commencing its Phase 1b human clinical study of Atu027 in cancer patients in 2009, provided the relevant approvals are forthcoming. This product is supported by an extensive pre-clinical package including data which has this month been published in the journal Cancer Research.

In addition, the Company can today confirm that it is in discussions with several third parties regarding the funding and development of its siRNA product, target and technology platforms. Silence is actively considering a range of collaborations and partnerships. While these discussions progress, Silence is managing its cash reserves prudently in order to fund its ongoing activities.

The Company also confirms that it has identified a number of new targets and indication opportunities that it intends to progress in 2009.

Iain Ross, Chairman and CEO of Silence Therapeutics, said:

"The filing of this Clinical Trial Application is a very important milestone for Silence. Atu027 is a systemically delivered siRNA product, which has data to support repeated dose administrations over a 28-day period. Moving to human clinical testing in 2009 will be a significant step forward.

"I am also pleased to confirm that by managing our cash reserves prudently the Company will have sufficient cash to fund its business regardless of whether the ongoing partnership discussions are concluded in 2008 or in 2009."

Ends

Enquiries:

For further information, please contact the following:

Silence Therapeutics plc

Iain Ross, Chairman and CEO

Melvyn Davies, Finance Director

+44 (0) 20 7307 1620Powerscourt+44 (0) 20 7250 1446Paul DurmanKay LarsenNominated Advisers

Nomura Code Securities Limited

+44(0)20 7776 1200

Chris Collins

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

Silence Therapeutics plc (AIM: SLN) is a leading European RNAi focused biotechnology company.

RNA interference (RNAi) is a Nobel Prize winning technology and 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.

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

Following the granting of its patents in Europe, Australia and the USA, Silence Therapeutics is one of only two companies worldwide with a proprietary position on composition of matter for siRNA therapeutics.

Silence's lead internal product, Atu027, is a proprietary AtuRNAi molecule in preclinical development for systemic cancer indications. Atu027 has successfully completed single and repeat dose toxicology and geno-toxicology studies, as well as a 28-day toxicology study using multiple dosing regimens. Silence plans a regulatory filing in 2008 to commence clinical trials for Atu027.

In March 2008 Silence Therapeutics announced a collaboration with AstraZeneca focused on the development of a range of novel delivery approaches for siRNA molecules. Under the terms of the agreement both Silence Therapeutics and AstraZeneca will be allowed to commercialize the truly novel delivery systems that the two partners develop together.

Silence Therapeutics has granted a licence to AstraZeneca to develop novel AtuRNAi therapeutics against five specific targets, including those in respiratory indications. This collaboration was the first industry validation of the potential application of Silence Therapeutics' proprietary AtuRNAi molecules and solidified the Company's leadership position in field of RNAi therapeutics.

The Company's AtuRNAi technology also has been sublicensed to Pfizer via Quark's license to them of the compound RTP-801i-14 for the treatment of age-related macular degeneration (AMD) and a number of other indications. This compound entered a phase II clinical study in July 2008. Silence Therapeutics also has licensed to Quark rights to the AtuRNAi structure for Quark's proprietary compound, AKIi-5, which is in a Phase I human clinical study for treatment of acute kidney injury.

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

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.