Safety Data For Anti-RSV Antibody Is Promising

Anti-RSV Antibody

MedImmune, Inc. announced results from two important studies presented at the 2007 Infectious Diseases Society of America (IDSA) 45th Annual Meeting adding to the body of knowledge about respiratory syncytial virus (RSV). RSV is a viral pathogen that produces annual outbreaks usually between fall and spring. While RSV typically manifests cold-like symptoms in healthy children, it can prove to be a very serious respiratory illness for premature infants and is the leading cause of respiratory infections for newborns each year. MedImmune has long been committed to developing and improving products for prevention of RSV disease and to enhancing the body of knowledge about RSV epidemiology.

"MedImmune continues to forge ahead with its aggressive strategy to help combat RSV disease," said Edward M. Connor, M.D., executive vice president and chief medical officer. "We are pleased to present new Phase 2 data at IDSA regarding motavizumab, a key investigational monoclonal antibody (MAb) within our product development portfolio that we are currently preparing for regulatory submission in the United States."

Connor added, "We will also present data regarding RSV surveillance at IDSA. These data show regional variability of RSV in the community, particularly in the southernmost United States. We believe that a better understanding of the regional variation in the timing of RSV may help inform decisions about timing of RSV prophylaxis for children at risk for serious RSV disease."

About RSV

Each year, up to 125,000 infants in the U.S. are hospitalized with severe RSV infections, the leading cause of lower respiratory tract infections in infants in the United States. RSV is the most common respiratory infection in infancy or childhood. Approximately one-half of all infants are infected with RSV during the first year of life, and nearly all children have been infected at least once by the time they reach their second birthday. Children born prematurely as well as those with chronic lung disease (CLD) or congenital heart disease (CHD) are at highest risk for severe disease and hospitalization due to RSV. The virus may also cause severe illness in other high-risk groups such as the elderly, those with underlying respiratory or cardiac disease, and those with compromised immune systems (e.g., bone marrow transplant patients).

About Motavizumab

Motavizumab, formerly known as Numax, is an investigational humanized MAb being evaluated for its potential to prevent serious lower respiratory tract disease caused by RSV in pediatric patients at high risk of RSV disease. Phase 1 and Phase 2 study data have been reported showing that motavizumab appears to have a similar safety and pharmacokinetic profile to Synagis (palivizumab) in infants. Additionally, in early phase studies children treated with motavizumab had reduced RSV replication in the upper respiratory tract. In its first pivotal trial, which was a head-to-head comparative trial with Synagis (palivizumab), motavizumab met its non-inferiority objective by demonstrating a 26-percent relative reduction in RSV hospitalizations and also showed a statistically significant 50-percent relative reduction in the incidence of RSV lower respiratory tract infections requiring outpatient management, a secondary endpoint.