LONDON (Reuters Health) Mar 14 – GlaxoSmithKline's hepatitis A vaccine Havrix could offer protection for up to 30 years, according to a study presented this week at the 10th International Congress on Infectious Diseases in Singapore.
Previously, experts believed that protection only lasted for ten years, at which point re-vaccination was necessary. However, according to a company news release, the new data mean adults could be protected for a substantial proportion of their adult life.
The study involved 115 adults who were vaccinated with Havrix in Belgium in 1990. Annual follow-up visits determined the long-term immunogenicity and persistence of hepatitis A antibody levels.
Antibody persistence and protection was demonstrated up to 10 years after vaccination, and when the trial data was fed into a previously developed mathematical model, results showed that protective antibody levels could be "expected to persist for at least 20-30 years assuming an annual decrease rate of 14%."
Professor Pierre Van Damme, Centre for the Evaluation of Vaccination, WHO Collaborating Centre for Prevention and Control of Viral Hepatitis, University of Antwerp, Belgium, and senior clinical trial investigator, said in a news release, "We have known for some time that this hepatitis A antigen is safe and effective."