Silence Therapeutics Unaudited Preliminary Results 2011 - March 2012. Featuring 2011 Highlights, an overview of Silence's performance and products, and an analysis of the commercial landscape of the field of RNAi.

1. Unaudited Preliminary Results 2011
21 March 2012

2. New Team members with Proven Track Record of building value
For shareholders
– Anthony Sedgwick, Ph.D., Chief Executive Officer
( Biotech Entrepreneur Novacta, Daniolabs, Cambridge Biotechnology, Roche)
– George Büchner, Ph.D., Head of Business development
(Novacta, Haptogen, Pharma Ventures)
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3. 2011 Highlights
– Positive interim data presented at ASCO
– Data showed excellent safety and indications of potential efficacy
– Leadership position validated by three new partnerships
– Top 10 pharma company, InteRNA Technologies and miRNA Therapeutics
– Further deal signed with miRagen Inc in January 2012
– Positive clinical results from partners
– Quark and Pfizer positive Phase II results in diabetic macular oedema
– Organisation streamlined
– Californian facility was closed, Board membership reduced
– Enhanced commercial focus
– New business development team recruited
– Intellectual property strengthened
– PKN3 patent issued in Japan, Zamore re-issued in US, Tuschl I clarified (Europe)
– Fundraising of £5.51m (net of expenses) in May 2011
– To fund development of pipeline and investment in RNAi technology platform
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4. 2011 Post year-end Highlights
– Dr Tony Sedgwick was promoted to Chief Executive Officer
– Deal announced with miRagen Therapeutics for the delivery of microRNAs using
the DBTC liver delivery systems
– Silence's second deal on DBTC and third for microRNAs
– Creation of a Scientific Advisory Board
– Two Key Opinion Leaders in the area of liver disease –announced today
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5. RNAi – James Watsons vision 2012
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6. An Overview of Silence Therapeutics
• European Biotechnology Company
• Listed on LSE (AIM) with operations
centralised in Berlin
• Cutting Edge technology- RNAi (Ribose
Nucleic acid Interference)
• Experienced New Management Tony
Sedgwick CEO –Geo Buchner Business
Several value drivers:
• External Milestones and Royalties (Quark)
• Internal Phase I First in Class Cancer Therapy
(To be completed
mid-2012)
• Low cost preclinical Pipeline
• Strong IP (e.g. AtuRNAi, Licenses
to Fire & Mello and Zamore Patents)
• One of only 2 companies with prosecuted
patents in area
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7. What is RNAi
Transformative technology
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8. RNAi can “Silence” Undruggable problem genes
22,000 genes
Human Genome
At the origin of numerous
diseases
The RNAi technology
can target ALL OF THEM
Targets that can be
Stabilised AtuRNAi
blocked by small
Naked can target All
molecule drugs or
Genes
antibodies
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9. Two value drivers: External and Internal
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10. Potential External revenue streams
Novartis Pfizer Pfizer/Quark Novartis/Quark
$3-11 million $4 million $85 million $71-77 million
2012 2014 Remaining milestones
Total milestone potential: approx $170 million
PLUS further potential milestone payments from the AstraZeneca collaborations
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11. Commercial landscape:
Delivering the great promise of RNAi
Delivery Development of
challenges successful delivery
Identified solutions
siRNA
technology
trigger
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12. And Internal value drivers…
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13. Silences AtuRNAi plus Disease “bespoke”
delivery system makes a drug
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14. Atu027: New Cancer treatment in Phase I
• Atu027 ‘silences’ the
production of PKN3 a Key
regulator of blood and lymph
vessel formation
• Inhibition of PKN3 leads to:
• reduced oxygen supply to
tumour
• reduced tumour
growth/metastases
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15. Atu027 is RNAi against PKN3 plus Atuplex
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16. Atu027: successfully progressed to a phase I
Investment
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17. Atu027 is safe in man and could be a new
medicine for treating difficult cancers
• Atu027 Phase I interim data demonstrates safety (ASCO 2011)
• 10 out of 27 patients showed stable disease after treatment period
• Atu027 very well tolerated - effective dose exceeded
• Phase I results expected to report in mid-2012
• Biomarker data currently under evaluation
• Looking for Co development partner
• Validates AtuPLEX™ delivery technology
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18. AtuRNAi plus DACC system makes a drug for treating
lung Cancer and life threatening lung disease
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19. Silence´s DACC delivery system: targets siRNAs to the lungs
• Address lung-specific diseases
e.g. acute lunG
injury/ARDS/Cancer by
delivering siRNA primarily to
the lungs
• Single dose sufficient to inhibit
target gene
• Expression in the lungs for up
to a month
• Atu111 in preclinical
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20. AtuRNAi plus DBTC system makes a drug for treating
liver Cancer and life threatening liver disease
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21. Silence´s DBTC: targets siRNAs to the liver
• Address liver-specific diseases
e.g. HCC, ischemia reperfusion
injury
• Single dose inhibits gene
expression in the liver for up to 1
week
• Well tolerated (up to 8.3 mg/kg)
• Preclinical studies ongoing
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22. Silence’s Revenue Stream
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23. Two value drivers: External and Internal
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24. Silence Power………………….
• New Management with proven track record
• Cutting Edge technology
• First in Class RNAi new cancer therapy
• One of only two companies with Prosecuted patents in area
• Lean organisation
• Pipeline of drugs and deals
• Undervalued
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25. Results for 2011
GBP ‘000s 2011 2010
unaudited audited
Revenue 694 2,366
R&D spend (3,361) (5,821)
Admin costs (2,647) (5,203)
Restructuring costs (472) -
Operating loss (5,786) (8,658)
Other income/(expense) 49 (137)
Loss after tax (5,737) (8,795)
Net cash 3,688 3,567
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26. Newsflow 2012
Update on AstraZeneca collaboration January 2012
Sign delivery collaboration with miRagen January 2012
Start of Phase IIb trial of PF’-655 in DME (Quark/Pfizer) 1Q 2012
Sign further collaboration agreements 1H 2012
Completion of enrolment in Atu027 trial 1H 2012
Start of Phase II trial of QPI-1002 in AKI (Quark/Novartis) 1H 2012
Publication of white paper on delivery technologies 1H 2012
Completion of Atu027 phase I trial Mid 2012
Completion of phase II trial of QPI-1002 delayed graft function 2H 2012
Start of phase Ib/II trial of Atu027 2H 2012
Further patent issuances 2H 2012
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27. Disclaimer
The statements made in this presentation may
contain certain forward-looking comments. Actual
events or results may differ from the Company’s
expectations. In addition to the matters described in
the presentation, future actions by the European
Agency for Evaluation of Medicinal Products, the
U.S. Food and Drug Administration or equivalent
regulatory authorities in other countries and results
of pending or future clinical trials, as well as other
risk factors outlined from time to time in the
Company’s regulatory filings, may affect actual
results achieved by the Company. The Alternative
Investment Market (AIM) has not reviewed and does
not accept responsibility for the adequacy or
accuracy of this presentation.
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28. Key peers
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