BACKGROUND: Patients with chronic hepatitis C are at risk of additionalliver damage when infected with other hepatotropic viruses, and should be vaccinated against HAV andHBV. However, the optimal dose and schedule are still being debated. In this study we assessed hepatitisB vaccine immunogenicity in patients with chronic hepatitis C at one-year follow-up. The effect of interferonalpha treatment on vaccine safety and anti-HBs response was also evaluated. MATERIAL/METHODS: 48 hepatitisC patients were enrolled, of whom 12 were on interferon treatment. Recombinant HBV vaccine was administeredon a 0-1-6 month schedule, and anti-HBs titers were measured at months 1, 2, 7, and 18. RESULTS: Theoverall seroprotection rate at month 7 was 72.9% in hepatitis C patients, compared to 90.9% in the controls.Subjects with chronic hepatitis C had significantly lower percentages of good responders: 50% versus90.9%. At month 18, only 34.1% of the HCV patients had seroprotective titers of anti-HBs, compared to90% in the control group. At all study points there were no significant differences in seroconversionrates and seroprotection rates between subgroups of hepatitis C patients receiving interferon or thosewithout antiviral treatment. CONCLUSIONS: Hepatitis C is associated with decreased HBV vaccine response.We suggest that postvaccination anti-HBs testing should be performed in all hepatitis C patients, andadditional vaccine doses should be provided to those without protection. Alternatively, higher dosesof vaccine (40 Kg) may be considered. Treatment with interferon was safe and well tolerated.

Keywords: Hepacivirus, Hepatitis B Antibodies, Hepatitis B Vaccines, Hepatitis C, Hepatitis C Antibodies, Interferon-alpha, Interferons, Liver, Recombinant Proteins, Time Factors