RESUMO
<p><b>OBJECTIVE</b>To determine the lamivudine response of HBV genotypes in patients with HBV DNA positive chronic hepatitis.</p><p><b>METHODS</b>Clinical data from 235 patients in the original trial were analyzed.</p><p><b>RESULTS</b>135 patients received lamivudine and 100 patients as controls. Almost all patients had HBV genotypes B or C. Antiviral response were 92.9% and 75.9% in lamivudine-treated patients (chi-square = 6.628, P < 0.05) and 9.8% and 8.5% in untreated controls (P > 0.05) with HBV genotype B and C, respectively. The incidences of lamivudine-induced mutation in YMDD motif were 3.6% and 16.5% in HBV genotype B and C, respectively (chi-square = 5.508, P < 0.01). We identified HBV genotype B, elevated pretreatment alanine aminotransferase (ALT) levels, and low pretreatment HBV DNA levels as independent factors associated with antiviral response.</p><p><b>CONCLUSION</b>HBV genotype B was associated with a higher rate of lamivudine-induced HBV DNA clearance and lower rate of lamivudine-induced YMDD mutation compared with genotype C. HBV genotypes may be an important determinant of lamivudine therapy of chronic hepatitis B.</p>