Predictors of Therapeutic Outcome to Nucleotide Reverse Transcriptase Inhibitor in Hepatitis B Patients

Hepatitis B is a clinically important public health issue. Infection leads to hepatocellular carcinoma. Therefore, patients need antiviral therapy for prolonged period to prevent the complication of the disease. Data concerning chronic hepatitis B (CHB) patients with high hepatitis B virus (HBV) DNA are limited. The aim of the study was to check the efficacy of the nucleoside reverse transcriptase inhibitors (tenofovir) in terms of suppression of HBV DNA. The secondary end point in the study is to evaluate trends of predictive variables that predict outcome of treatment. In this specific study, we evaluated 140 CHB male and female patients, of these 110 completed 48 weeks of treatment. On the basis of hepatitis B e antigen (HBeAg), patients were stratified; HBV DNA and hepatitis B surface antigen (HBsAg) levels were measured along with liver function tests. All enrolled patients were given tenofovir disoproxil fumarate 300 mg daily before breakfast. Overall, 69.1% of patients showed virologic response. HBeAg-negative patient group showed 68% viral suppression and HBeAg-positive patient group showed 45.9% over 24 months of treatment, while at 48 months it was shown to be 76.7% and 54.1%, respectively. None of the patients suffered HBsAg loss during the 48 months. Baseline high HBV DNA level was found as a significant predictor of response (OR, 1.9; 95% CI = 1.23-3.9, p = 0.005). None of the patients observed had serious adverse events. Mutations in the RT region of polymerase gene are shown to be associated with resistance to antiviral drugs. Among patients suffering with chronic HBV infection, HBeAg-negative patient group have better virologic response as compared with HBeAg-positive group. Higher concentration of HBV DNA at baseline has negative prediction for sustained viral suppression. The A-B motif interdomain rtL122F mutation was found in nonresponder patients in our study. Another mutation rtN248H observed in E motif considered to have effect on DNA primer grip, which forms part of binding pocket.