Comparative Immune Responses of Two Commercial Hepatitis B Vaccines

One hundred healthy hepatitis B virus (HBV) seronegative persons were enrolled in a single blind randomized study to compare antibody and clinical responses to yeast recombinant S antigen vaccine (YSHBV) (Hepavax-gene, 1 ml: 20 μgr = one dose) and Chinese hamster ovary cells (CHO) recombinant Pre S2 + S vaccine (CS2SHBV) (Genhevac B, 0.5 ml: 20 μgr = one dose). 50 participant (group I) received 20 μgr of YSHBV by intramuscular (IM) injection at 0,1 and 6 months (mo). 50 participants (group II) received 20 μgr of CS2SHBV by IM injection at 0, 1 and 2 mo. Serological and biochemical responses were measured at 0, 1, 2, 3, 6 and 7 months in both groups. The proportion of vaccines with minor local complaints (mainly local pain, myalgia ) and proportion developing antibody to surface antigen (antiHBs) were similar for both vaccine groups (p >0.05), but anti-HBs titers were generally higher among recipients of CS2SHBV. Anti-HBs developed in 92% and 96%, in group I and II by 7 month, respectively. These data imply that YSHBV vaccine is as well tolerated and immunogenic as CS2SHBV vaccine. However, further studies are necessary to compare the duration of immunity after vaccination for two vaccines. [Journal of Turgut Özal Medical Center 1996;3(3):169-172]