Three-year efficacy and safety of tenofovir in nucleos(t)ide analog-naive and nucleos(t)ide analog-experienced chronic hepatitis B patients

Background and Aims:This study compared the efficacy and safety of tenofovir disoproxil fumarate (TDF) up to 3years of innucleos(t)ide analog (NA)-naive and NA-experienced chronic hepatitis B (CHB) patients. Methods:Tenofovir disoproxil fumarate-treated NA-naive and NA-experienced CHB patients were retrospectively analyzed. Results:After 3years of TDF therapy, 97.7%, 71%, and 45.5% NA-naive patients achieved a virological response, alanine aminotransferase normalization, and hepatitis B e antigen seroconversion, respectively. Compared with NA-naive patients, NA-experienced patients without drug resistance and infected with lamivudine/telbivudine-resistant mutants showed similar results. In contrast, patients previously infected with adefovir-resistant mutants and with a suboptimal entecavir response showed significantly lower rates of virological response and hepatitis B e antigen loss/seroconverion than NA-naive patients. Mean estimated glomerular filtration rate markedly reduced within 12months of TDF therapy; however, it did not decrease significantly during 12-36months of treatment. Diabetes mellitus was an independent predictor of a 0.5mg/dL increase above baseline in serum creatinine level, and age, hypertension, diabetes mellitus, and baseline creatinine level were independent factors for >20% decline in estimated glomerular filtration rate from baseline. Liver stiffness measurements improved significantly, but bone mineral density did not change significantly during treatment. Hepatocellular carcinoma incidence was low at 36months. Age of >60years, cirrhosis, a low baseline platelet count and a high -fetoprotein level at 12months were significant predictors of hepatocellular carcinoma development. Conclusions:Tenofovir disoproxil fumarate is effective and safe for NA-naive and NA-experienced CHB patients and should be used cautiously in patients with comorbidities because of a renal dysfunction risk.