Clinical Experience with the PreS1-containing Hepatitis B Vaccine (HG-3) in Different Nonresponder Groups

Conventional hepatitis B (HB) vaccines, such as the yeast-derived S-vaccine, have some serious drawbacks with regard to efficiency, as shown by the nonresponsiveness rates seen particularly in elderly persons or immunosuppressed patients. We assessed the efficacy of a genetically engineered preS1-containing HB vaccine (HG-3) in nonresponders to the S-vaccine. HG-3 was given to 5 groups of nonresponders: (1) healthy and under 40 years (n = 60); (2) healthy and over 40 (n = 13); (3) hemodialysis patients (n = 40); (4) liver transplant patients (n = 35); and (5) heart transplant patients (n = 84). Seroconversion with HG-3 was observed in 100%, 100%, 92%, 49%, and 40% of the vaccinees in groups 1 to 5, respectively. Both antibody to hepatitis B surface antigen (anti-HBs) and anti-preS antibodies were efficiently induced in these previous nonresponders. These results indicate that HG-3 is remarkably effective in inducing antibodies in S-vaccine nonresponders, even in elderly persons or immunosuppressed patients, and also suggest that the added preS region activates T cells that help produce anti-HBs.