ABSTRACT
Results of registration trial of combination vaccine for prevention of hepatitis A and B are presented. The trial was conducted in 5 centers of Russia in 2004-2005 with full accordance to good clinical practice requirements and standards for multicenter open randomized trials. Immunogenicity of studied combination vaccine Twinrix was evaluated in comparison with two simultaneously administered monovalent vaccines against hepatitis A and B (Havrix and Engerix-B) in 200 healthy subjects aged 18-40, which were seronegative to hepatitis A and B. Reactogenicity based on interviewed and non-interviewed symptoms ranged on intensity was assessed also. 1 month after completion of primary vaccination all subjects in both groups were seropositive to hepatitis A. Sero-protection level of antibodies to hepatitis B virus was detected in 98.9% of participants vaccinated with Twinrix and in 95.6% of participants vaccinated with Engerix-B and Havrix. Overall, reactogenicity of vaccines was minor, marked adverse events caused by vaccination were rare (approximately 1%). Study shows that combination vaccine against hepatitis A and B (Twinrix) at least non inferior in terms of immunogenicity, safety and tolerability to monovalent vaccines (Havrix and Engerix-B), were registered in Russia.
