Hepatitis B genotypes in chronic hepatitis B and lamivudine therapy

The influence of hepatitis B virus (HBV) genotypes on the natural history and the response to treatment of patients with chronic hepatitis B are of potential interest. Compared to the patients with HBV genotype C, those with genotype B were of a younger age and had a higher cumulative rate of hepatitis B e antigen (HBeAg) seroconversion during the initial 6 years of follow-up. The earlier HBeAg seroconversion in the patients with genotype B, however, did not provide them with a benefit in terms of a reduced risk of developing long-term complications. The response to lamivudine therapy was evaluated in 21 patients infected with HBV genotype B (all of subtype Ba) and 61 with genotype C. There were no differences in the virological response to lamivudine therapy, based on the reduction in median logarithmic HBV DNA titer as well as alanine aminotransferase (ALT) levels, normalization of ALT and the rate of HBeAg seroconversion between the patients with genotypes B and C. No differences were noted either, in the frequency of YMDD mutants at week 52 or the cumulative risk of HBV DNA breakthroughs with YMDD mutations during long-term lamivudine therapy (median 37.5 months). In conclusion, there is no influence of HBV genotypes on the development of long-term complications and lamivudine therapy in Hong Kong.