Silence Therapeutics Executes Strategic Plan to Optimize and Integrate Technologies and Assets From Intradigm Merger

Company Consolidates Research Activities in Berlin and Operations in Palo Alto

LONDON, April 13, 2010 - Silence Therapeutics plc (AIM: SLN) ("Silence" or the "Company")
announces that the Company is executing a strategic plan designed to
optimally organize its resources following its recent merger with Intradigm
Corporation. Moving forward, all research activities related to Silence's
novel RNA interference (RNAi) therapeutic platforms, including technologies
that have emerged from both Silence and Intradigm, will take place at the
Company's Berlin location. Other functions including operations, business
development, legal and certain drug development activities will be conducted
in Palo Alto. As a result of this consolidation, Silence has eliminated
approximately 20 positions, predominantly in the area of research and
development, from the Company's Palo Alto and Berlin locations. Silence
expects this move to result in a significant reduction in the Company's burn
rate moving forward. The Company expects to maintain the current headcount
and finance function in its London office.

"Following months of strategic planning, we have developed a plan that
eliminates duplication between the sites and focuses key activities in
specific locations. We believe this new structure will allow us to most
effectively advance Silence's novel RNAi therapeutic platforms, support our
ongoing partnerships and focus our business development efforts that are
critical to establishing new partnerships," stated Philip Haworth, Ph.D.,
chief executive officer of Silence Therapeutics. "While there are many
benefits to this reorganization, the elimination of certain positions is an
unfortunate result. Each member of the Silence and Intradigm teams has
contributed significantly to Silence's groundbreaking science. I wish to
personally express my sincere gratitude and appreciation to every employee
who has helped to create our position of leadership in RNAi therapeutics."

As part of the recent merger, Silence acquired the comprehensive RNAi
therapeutic platform developed by Intradigm including proprietary delivery
technologies, potent short interfering RNA (siRNA) sequences and innovative
siRNA structural features. The company expects this reorganization to be
completed by June 2010.

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

Silence Therapeutics plc (AIM: SLN) is a leading global biotechnology
company dedicated to the discovery, development and delivery of targeted,
systemic RNA interference (RNAi) therapeutics for the treatment of serious
diseases. The company possesses multiple proprietary siRNA delivery
technology platforms including AtuPLEX(TM), a system that enables the
functional delivery of siRNA molecules to targeted diseased tissues and
cells, while increasing their bioavailability and intracellular uptake. A
second, complementary delivery technology known as PolyTran(TM) uses a
library of novel peptide-based biodegradable polycationic polymers for
systemic siRNA administration. Additionally, the company has 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. Silence's unique RNAi assets also
include structural features for a next generation of RNAi molecules and
additional proprietary siRNA sequences against more than 50 highly valued
oncology and other disease targets.

The company's strong and diverse intellectual property portfolio includes
exclusive licenses from the University of Massachusetts on three patent
families associated with the Zamore "Design Rules," which cover broad
structural features of siRNA design for more potent next generation siRNA
sequences.

Silence Therapeutics is headquartered in London, UK, with operations in
Berlin and Palo Alto, CA.

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.

Phil Haworth of Silence Therapeutics, +1-650-855-1514, p.haworth at silence-therapeutics.com; or Richard Potts or Jonathan Senior, both of Nomura Code Securities, +44-020-7776-1200; or media, Tim Brons, +1-415-675-7400, tbrons at vidacommunication.com, or investors, Stephanie Diaz, +1-415-675-7400, sdiaz at vidacommunication.com, both of Vida Communication, for Silence Therapeutics plc