Children who received a Sanofi hepatitis B vaccine that was later taken off the market had a robust immunological memory against the virus five years later, according to researchers. Hexavac and Infanrix Hexa were licensed in Europe for primary immunization of children against diphtheria, tetanus, pertussis, poliomyelitis, hepatitis B and invasive infections caused by Haemophilus influenzae b in 2000. But in 2005, Hexavac was suspended because of concerns about the long-term immunogenicity of its Hepatitis B component.
However, in an open-label, randomized, controlled, multicenter study in six local health units and at the Bambino Gesù Pediatric Research Hospital in Italy, researchers measured antibody concentrations five years after immunization of infants with Hexavac or Infanrix Hexa, according to The Lancet Infectious Diseases. More than 1,500 children were included in the study. Of those, 831 children who received Hexavac and 709 who received Infanrix Hexa were included in their analysis.
Children with concentrations of antibodies to hepatitis B surface antigen lower than 10 mIU/mL were randomly assigned to receive a booster of HBVaxPro or engerix B monovalent hepatitis B vaccine and tested two weeks later. Bloomberg notes that more than 90 percent of children in both groups who received a booster shot had a sufficient number of antibodies to fight infection, suggesting that immune systems in young children are able to recall responding to the initial inoculation years later. Furthermore, the results suggest that frequent booster shots aren't needed--although further research is needed.
Separately, Sanofi Pasteur is buying Orlando, FL-based VaxDesign for $55 million up front and an additional $5 million in milestones. VaxDesign, which started business in 2004 by Bill Warren, creates an artificial immune system used to test drugs and other products. It uses blood samples from Florida's Blood Centers to create its product, which provides an alternative to animal testing.
Sanofi says that VaxDesign's Modular IMmune In-vitro Construct technology will help it better filter preclinical stage candidates to pick the best compounds for Phase I human clinical trials. Better selection at an early stage can help avoid large (and costly) late-stage failures.
- read the study summary
- get more from Bloomberg
- read the Orlando Business Journal's story on VaxDesign
- see the MedPage story
ALSO: Biologists at The University of Texas at Arlington have found fragments of the modern Hepatitis B virus inside the genomes of songbirds such as the modern day zebra finch. News