Objective: To evaluate the safety and immunogenicity of local produced hepatitis B (HB) vaccine and to lay a basis for formulating an immunization strategy.
Methods: Two batches of local produced and two batches of imported yeast derived recombinant HB vaccine (YDV), and four batches of local produced Chinese hamster ovary cell derived recombinant HB vaccine (CHOV) were administered to 550 children in primary schools to study their immunogenicity one year after immunization.
Results: No severe adverse reaction was found in all vaccinee. Positive seroconversion rate was more than 90 percent one month after completion of three-dose immunization with all kinds of HB vaccine mentioned above, and then declined slowly. Titer of antibody against hepatitis B surface antigen (anti-HBs) in those vaccinated with two batches of local produced YDV, except four groups, was significantly lower than that in those with imported YDV and local produced CHOV seven months after first-dose immunization, but no difference between local produced YDV and imported Merck vaccine and CHOV was found one year after immunization. Mean geometric titer (GMT) of anti-HBs reached the peak seven months after immunization in those vaccinated with all batches of HB vaccine except for the YDV imported from Amgen Co. There was no significant difference in positive seroconversion and GMT of anti-HBs between different batches of local produced YDV and CHOV.
Conclusion: Safety and immnogenicity of local produced recombinant HB vaccine is as good as those of imported one in immunization for primary school children.