"RSV is a serious respiratory disease that can have significant effects onchildren. As a leader in pediatric medicine, MedImmune is committed todeveloping therapies that can combat the most common cause of pediatricrespiratory illness," said Filip Dubovsky, M.D., M.P.H, vice president,clinical development, vaccines. "Because respiratory illness due to RSV occursin otherwise healthy children, developing a vaccine is a public healthpriority."

MedImmune is a world leader in the development of innovative therapeuticbiologic products for prophylaxis and prevention of infectious diseases. ThisPhase 1/2a clinical trial is designed to assess the safety, tolerability,immunogenicity and viral shedding of the intranasal RSV vaccine in infants andyoung children. It is a randomized, double-blind, placebo-controlled andmulti-dose study that will enroll 320 children.

The investigational vaccine, MEDI-559, is being developed through aCooperative Research and Development Agreement (CRADA) with the NationalInstitute of Allergy and Infectious Diseases (NAID), part of the NationalInstitutes of Health, to help address RSV disease in children. The vaccine wasoriginally developed in the NAID Division of Intramural Research by a team ledby Peter L. Collins, Ph.D. and Brian R. Murphy, M.D.

About RSV

RSV is the most important cause of viral lower respiratory tract illnessin infants worldwide. Each year, an estimated 125,000 infants in the UnitedStates are hospitalized with severe RSV infections. RSV is the most commonrespiratory infection in infancy or childhood that circulates in the NorthernHemisphere predominantly in the fall and winter months. Approximately one-halfof all infants are infected with RSV during the first year of life, and nearlyall children have been infected at least once by the time they reach theirsecond birthday.

About MedImmune

MedImmune is a leading innovation-focused biotechnology company whosemission it is to provide better medicines to patients, new medical options forphysicians and rewarding careers to employees. Dedicated to advancing scienceand medicine to help people live better lives, the company is focused oninfection, oncology, respiratory disease and inflammation, cardiovascular /gastrointestinal disease and neuroscience. Headquartered in Gaithersburg,Maryland, MedImmune has approximately 3,000 employees worldwide and is thewholly owned biologics business for AstraZeneca plc (LSE: AZN.L, NYSE: AZN).For more information, visit MedImmune's website at http://www.medimmune.com.

SOURCE MedImmune