Hepatitis B third-generation vaccines: improved response and conventional vaccine non-response - third generation pre-S/S vaccines overcome non-response

A new triple-S containing recombinant hepatitis B vaccine was evaluated in terms of immunogenicity and reactogenicity in a cohort of healthy healthcar e professionals who were persistent nonresponders to the currently licensed hepatitis B vaccines. One hundred subjects were allocated randomly to rece ive two doses of 5, 10, 20 or 40 mu g of a new hepatitis B vaccine 2 months apart. The overall seroconversion rate was 70% with a single dose of 20 mu g of the vaccine being as effective as two doses of either 20 mu g or 40 m u g of the vaccine formulation in terms of seroconversion, seroprotection a nd geometric mean titres.