New vaccines against hepatitis B.

The high cost and limited availability of the plasma-derived hepatitis B vaccines have prevented their widespread use, especially in the less developed areas where they are needed most. Hepatitis B vaccines produced by recombinant technology seem to offer a solution to these difficulties. Studies reported up to now confirmed the safety of this vaccine. Immunogenicity studies in various population groups showed that seroconversion rates and antibody titres are comparable to plasma vaccine. In assessing the efficacy of the vaccine, information concerning the quality of the anti-HBs induced should complement these data. Potential live vaccines using recombinant vaccinia viruses have been constructed for hepatitis B. Preliminary studies in rabbits and chimpanzees indicated the feasibility of future using a recombinant vaccinia virus. Chemically synthesized polypeptides corresponding to relevant epitopes of HBsAg may be useful as synthetic vaccines offering the advantages of a cheap viral immunogen free from irrelevant antigenic determinants. Finally preliminary studies for an idiotypic vaccine have already been reported.