Pharmaceutical company GlaxoSmithKline has announced that is Rotarix rotavirus vaccine is effective at preventing rotavirus gastroenteritis during the first two years of life. The results of a multi-center, randomized, double-blind, placebo- controlled phase III clinical trial in Europe showed that, through two rotavirus seasons, the vaccine was highly efficacious against rotavirus hospitalizations with a 96 percent success rate.

"The candidate vaccine contains a live, weakened form of natural human rotavirus derived from the most common human rotavirus strain with the goal of offering protection against the most commonly circulating and emerging rotavirus serotypes by mimicking the protective effects of natural human rotavirus infection," said David I. Bernstein, MD, MA, Director, Infectious Diseases; Gamble Program at Cincinnati Children's Hospital Medical Center.

The rotavirus, a RNA virus, is the most common cause of viral gastroenteritis in infants. Around the world, around 600,000 die, mostly in developing countries. In 1998 a rotavirus vaccine was licensed for use in the United States, but in 1999 the manufacturer withdrew it after it was discovered that the vaccine may have contributed to an increased risk for bowel obstruction.

GlaxoSmithKline has to compete with Merck's RotaTeq, approved by the U.S. Food and Drug Administration in February 2006. That vaccine is highly expensive, with an announced a price of $187.50 for the standard three-dose regimen.

The U.S. Food and Drug Administration (FDA) is currently evaluating GSK's Biologics License Application (BLA) for the candidate rotavirus vaccine Rotarix. European researchers reported that Rotarix efficacy after two doses over two rotavirus seasons remained high at 79 percent and was 90 percent against severe rotavirus gastroenteritis.