Washington Editor

MedImmune Inc. released Phase III data showing that Synagis reduces respiratory syncytial virus related hospitalizations in young children with congenital heart disease.

MedImmune, along with its partner, Abbott Laboratories Inc., intends to submit the data in a supplemental application in the U.S. and Europe. Lori Weiman, senior director of corporate communications for Gaithersburg, Md.-based MedImmune, told BioWorld Today that the U.S. application is likely to be submitted by the end of the year.

Synagis, a humanized monoclonal antibody, won U.S. approval in 1998 for the prevention of serious lower respiratory tract disease caused by respiratory syncytial virus (RSV) in pediatric patients at high risk of contracting the disease, primarily defined as children with chronic lung disease and those born prematurely. According to MedImmune's guidance released July 25, Synagis is expected to generate $630 million to $640 million in worldwide sales in 2002. The U.S. patient population is roughly 300,000.

Meanwhile, there are 32,000 children born each year with varying degrees of congenital heart disease (CHD), and MedImmune believes 16,000 could be eligible for Synagis as a prophylaxis.

Data from the Phase III trial of CHD patients were presented at the American Academy of Pediatrics 2002 National Meeting in Boston.

The four-year, double-blind, placebo-controlled study was designed to assess the safety and efficacy of Synagis in children less that 2 years old with serious CHD. The study was conducted at 76 centers and included 1,287 children in North America and Europe. Children were randomized to receive five monthly intramuscular injections (15mg/kg) of either Synagis or placebo during the RSV season, which in the Northern Hemisphere generally runs from October through April.

Compared to placebo, the Synagis group had 45 percent fewer hospitalizations due to RSV (p=0.003). Further, the data showed there were significantly fewer RSV-related hospital days (p=0.003) and fewer days of increased oxygen usage (p=0.014) in the treated group than in the placebo group, the company said.

"Children with CHD who are hospitalized with RSV have substantially higher rates of mortality and morbidity than those children who do not have CHD. They are also a more difficult patient group to study," a prepared statement released by Henry Sondheimer, professor of pediatrics at the University of Colorado Health Sciences Center, said. "As such, the results of the current study will be very useful in helping pediatricians and pediatric cardiologists identify CHD patients who will benefit from prophylaxis with Synagis to prevent RSV."

MedImmune's stock (NASDAQ:MEDI) closed Friday at $27.70, up 1 cent.