Three-year efficacy and safety of tenofovir in nucleos(t)ide analog-naïve 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 3 years of innucleos(t)ide analog (NA)-naïve and NA-experienced chronic hepatitis B (CHB) patients. Methods:: Tenofovir disoproxil fumarate-treated NA-naïve and NA-experienced CHB patients were retrospectively analyzed. Results:: After 3 years of TDF therapy, 97.7%, 71%, and 45.5% NA-naïve patients achieved a virological response, alanine aminotransferase normalization, and hepatitis B e antigen seroconversion, respectively. Compared with NA-naïve 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-naïve patients. Mean estimated glomerular filtration rate markedly reduced within 12 months of TDF therapy; however, it did not decrease significantly during 12–36 months of treatment. Diabetes mellitus was an independent predictor of a ≥ 0.5 mg/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 36 months. Age of > 60 years, cirrhosis, a low baseline platelet count and a high α-fetoprotein level at 12 months were significant predictors of hepatocellular carcinoma development. Conclusions:: Tenofovir disoproxil fumarate is effective and safe for NA-naïve and NA-experienced CHB patients and should be used cautiously in patients with comorbidities because of a renal dysfunction risk.