Long-term effects of entecavir and tenofovir treatment on the fibrotic burden in patients with chronic hepatitis B.

Abstract

Antiviral therapy (AVT) induces fibrosis regression in patients with chronic hepatitis B. We investigated long-term effects of entecavir (ETV) versus tenofovir (TDF) on fibrotic burden. Treatment-naïve chronic hepatitis B patients who had begun ETV or TDF were recruited from four tertiary hospitals. The aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on four factors (FIB-4) were used to determine fibrotic burden. In the entire population (n=3277), although patients treated with ETV had higher baseline APRI (1.71 vs 1.07, P<0.001) and FIB-4 (3.60 vs 2.80, P<0.001) than those treated with TDF, significant fibrosis regression was identified during 6years of AVT in both ETV (APRI, mean 1.71→0.48, P<0.001; FIB-4, mean 3.60→2.21, P<0.001) and TDF groups (APRI, mean 1.07→0.43, P<0.001; FIB-4, mean 2.80→2.19, P<0.001). In patients without cirrhosis (n=2366), baseline APRI was significantly higher in ETV group than in TDF group (1.72 vs 0.97, P<0.001); however, they became similar after 6months. Similarly, baseline FIB-4 was significantly higher in ETV group than in TDF group (3.25 vs 2.35, P<0.001), but became similar from 4 to 6years. In patients with cirrhosis (n=911), baseline APRI (1.70 vs 1.34, P<0.001) and FIB-4 (4.62 vs 3.91, P=0.005) were higher in ETV group than in TDF, however, both parameters became statistically similar from 6months to 6years. Significant regression of APRI and FIB-4 was observed during long-term ETV and TDF treatment. Despite higher baseline fibrotic burden in ETV group, fibrotic burden between the groups eventually converged through significant fibrosis regression after 1 to 4years of AVT.