Public Health

Reduced-dose hepatitis A vaccine effective in children

Last Updated: 2007-09-17 17:40:19 -0400 (Reuters Health)

By David Douglas

NEW YORK (Reuters Health) - A pediatric formulation of the virosome-based hepatitis A virus (HAV) vaccine Epaxal (Berna Biotech) appears to be protective in children, according to European researchers.

"Lowering the antigen content of these vaccines doesn't change their efficacy profile," senior investigator Dr. Pierre van Damme told Reuters Health. "Non-inferiority is indeed shown vis-a-vis the full dosage Epaxal vaccine and the other commercialized vaccine Havrix," which is produced by GlaxoSmithKline.

In the August issue of The Pediatric Infectious Disease Journal, Dr. van Damme of the University of Antwerp, Belgium and colleagues note that they studied 308 children with a mean age of 8.9 years.

They were randomized to receive a full 0.5 mL dose of Epaxal, a reduced 0.25 mL dose of Epaxal, or a standard dose of Havrix Junior.

The team found that all of the vaccines were highly immunogenic and the reduced dose of Epaxal was not inferior to the other two vaccine approaches. None of the subjects withdrew from the study and there were no vaccine-associated adverse events.

"So dose-adapted virosome-based vaccines for children keep all the advantages of the full dose, and compare very well with current commercial HAV vaccines in children," continued Dr. Van Damme.

"Lowering antigen doses means that more vaccines can be produced with approximately the same production effort," he pointed out. "This will be important when large HAV programs in infants and children are launched, in particular in regions with an intermediate endemicity, such as South America and Eastern and Central Europe."

Pediatr Infect Dis J 2007;26:705-710.