1. Influenza A (H1N1) Vaccine Vaccines and Related Biological Products Advisory Committee Meeting, 23 July 2009 Raburn Mallory, M.D. Proprietary Vaccines and Related Biological Products Advisory Committee meeting, 23July 2009, Gaithersburg MD

2. 22 04/14/2008 – 6:00pmeSlide - P4815 - MedImmune Template Overview Influenza A (H1N1) 2009 Monovalent Vaccine Live, Intranasal Clinical studies planned and data availability Manufacturing plans and vaccine availability Vaccines and Related Biological Products Advisory Committee meeting, 23July 2009, Gaithersburg MD Proprietary

3. 33 04/14/2008 – 6:00pmeSlide - P4815 - MedImmune Template MedImmune’s 2009 monovalent live influenza A (H1N1) vaccine Intranasal delivery using a pre-filled single dose AccuSpray ™ device  0.2 mL/dose (0.1 mL in each nostril)  Contains no preservative or adjuvants Dose is fixed at 10 7±0.5 FFU/strain  Clinical efficacy studies conducted with trivalent seasonal vaccine, FluMist, used to establish dose for H1N1 monovalent vaccine FluMist replicates intranasally to generate a broad immune response  Cellular  Humoral  Mucosal High levels of efficacy seen in studies with trivalent FluMist  HAI titers not correlated with protection Proprietary Vaccines and Related Biological Products Advisory Committee meeting, 23July 2009, Gaithersburg MD

4. 44 04/14/2008 – 6:00pmeSlide - P4815 - MedImmune Template Clinical studies of our H1N1 vaccine are based on annual strain change procedure 7 previous annual clinical studies conducted in adults to incorporate new strains into trivalent seasonal vaccine, FluMist  Safety from studies used to allow strain change to proceed Two concurrent placebo-controlled clinical studies planned  MI-CP215: Healthy adults 18-49 years of age (n = 300)  MI-CP217: Healthy children 2-17 years of age (n = 300) Design and randomization  2 dose schedule (10 7±0.5 FFU/dose) delivered 1 month apart  Subjects randomized 4:1 (vaccine:placebo)  Subjects randomized 1:1 to have blood drawn 14 or 28 days after first dose Objectives  Demonstrate attenuation by evaluating fever rates  Evaluate solicited symptoms and adverse events  Evaluate serum immune responses after each dose Proprietary Vaccines and Related Biological Products Advisory Committee meeting, 23July 2009, Gaithersburg MD

5. 55 04/14/2008 – 6:00pmeSlide - P4815 - MedImmune Template Timing of data availability from studies* Proprietary Vaccines and Related Biological Products Advisory Committee meeting, 23July 2009, Gaithersburg MD FDA submission Content of submission Adult data available Pediatric data available 1 Day 8 safety data after Dose 1 8 Sept 200914 Sept 2009 2 Day 15 immunogenicity data after Dose 1 18 Sept 200923 Sept 2009 3 Day 29 immunogenicity data after Dose 1 Day 8 safety data after Dose 2 12 Oct 200916 Oct 2009 4 Day 29 immunogenicity data after Dose 2 2 Nov 20099 Nov 2009 * Timing reflects best case scenario of first subject in on August 17 th and no unexpected events occurring during study conduct or data analysis

6. 6 Manufacturing progress and key regulatory milestones A 6:2 reassortant virus made using reverse genetics 11 May 2009  23 separate variants evaluated Master virus seed selected for commercial manufacture 25 June 2009  Yields appear consistent with normal seasonal strains  Antigenically similar to CDC recommended strain Commercial scale manufacturing initiated 03 July 2009 Key regulatory milestones  Submission of strain change supplement  Review and release of H1N1 lots  Review and approval of second high speed fill line

7. 7 Timing of vaccine availability from manufacturing* Projected availability of influenza A (H1N1) bulk and filled doses by month Millions of doses, cumulative Vaccine availability limited by delivery device supply constraints Finished product capacity = ~40M filled doses  Limitation is availability of sprayers (from now until March 2010) Bulk capacity at current growth rates = ~200M doses * Availability of doses is based on current manufacturing schedule for having QC released doses available and is not linked to FDA release Bulk doses released Filled doses released AugSeptOctNovDecJanFebMar Fill line 2 approval

8. 88 04/14/2008 – 6:00pmeSlide - P4815 - MedImmune Template Acknowledgements Proprietary This project has been funded in whole or in part with Federal Funds from the HHS/ASPR/BARDA, under Contract No. HHSO100200900002I The content of this publication does not necessarily reflect the view or policies of the Department of Health and Human Services, nor does the mention of the trade names, commercial products or organizations imply endorsement by the U.S. Government. Vaccines and Related Biological Products Advisory Committee meeting, 23July 2009, Gaithersburg MD