HEPATITIS-B VACCINATION OF HEMODIALYSIS-PATIENTS - RANDOMIZED CONTROLLED TRIAL COMPARING PLASMA-DERIVED VACCINE WITH AND WITHOUT PRE-S2 ANTIGEN

Abstract. The pre‐S2protein of the hepatitis B virus envelope evokes anti‐pre‐S2antibodies and enhances the anti‐HBs response after vaccination in mice. In order to evaluate the immunogenicity of the pre‐S2Ag in man, 102 HBsAg, anti‐HBs, anti‐HBc‐negative haemodialysis patients were vaccinated at random according to one of four vaccination schedules: 5 μg plasma vaccine Pasteur (containing 1 % pre‐S2) or 20 μg plasma vaccine MSD (no pre‐S2) at 0, 1, 2, 4, 6 and 12 months; or 10 μg Pasteur or 40 μg MSD at 0, 1,2 and 6 months. Anti‐HBs levels were measured by RIA and expressed in IU 1‐1; anti‐pre‐S2response was evaluated by both EIA and Western blot analysis. Eighty‐four per cent (95% confidence interval: 75–93) of the patients exhibited an anti‐HBs response of 2 IU l‐1or more and 71% (95% confidence interval: 61–81) reached an anti‐HBs level of at least 10 IU l‐1 within 13 months of the start of vaccination. Anti‐HBs response correlated with age (the response rate decreased with increasing age) but not with either the type of vaccine or dosage. An anti‐pre‐S2response was observed in 16% (EIA) and 46% (Western blot) of the patients immunized with the Pasteur vaccine and none (EIA, Western blot) of the MSD group. The level of anti‐pre‐S2antibodies correlated with high anti‐HBs titres; an anti‐pre‐S2response occurred in only one anti‐HBs‐negative patient. The addition of 1% pre‐S2to the HBsAg plasma hepatitis B vaccine had no significant effect on the anti‐HBs response in haemodialysis patients and did not markedly broaden protective immunity. Further studies of recombinant vaccines with a higher pre‐S2content are needed to document the possibility of enhanced immunogenicity of pre‐S2Ag‐containing hepatitis B vaccines in man. Copyright © 1990, Wiley Blackwell. All rights reserved