OBJECTIVETo compare renal function in chronic hepatitis B (CHB) patients before and after antiviral treatment with either telbivudine or entecavir administered as monotherapy,as well as to assess the impact of these antivirals on renal function in patients with mild renal impairment and to provide evidence for optimizing each as an antiviral treatment of CHB.

METHODSA total of 120 patients with CHB were enrolled for study and treated with either telbivudine (600 mg/d) or entecavir (0.5 mg/d). The normalization rate of alanine aminotransferase (ALT), the undetectable rate of HBV DNA, the level of serum creatinine (CR) and the estimated glomerular filtration rate (eGFR) were compared from the baseline period to post-treatment week 52 weeks and to post-treatment week 104. The chi-square test and t-test were used for statistical analyses.

RESULTSAfter 104 weeks of telbivudine monotherapy, the patients showed significant improvement in renal function (vs. baseline), with improved creatinine level (t=2.917, P=0.005) and eGFR (t=-2.736, P =0.008). Treatment with entecavir monotherapy did not provide significant improvement in renal function (at week 104, creatinine and eGFR: t=-2.727, P =0.007 and t=2.218, P=0.028). However, subgroup analysis of the mean change in eGFR indicated that both telbivudinetreated patients and entecavir-treated patients who entered the study with the poorest eGFR (at baseline, less than 90 mL/min/1.73 m-2) had better eGFR improvement after treatment (25.93 ± 2.21, n=11 vs. 8.17 ± 10.14, n=7), and there was a significant difference between the telbivudine group than the entecavir group (t=4.323, P =0.001). Virological breakthrough was more frequent in the telbivudine group than in the entecavir group (at week 104, 15.0% vs. 1.7%, P=0.017).

CONCLUSIONCompared with entecavir monotherapy, telbivudine monotherapy provides a renoprotective effect in patients with CHB. While these results may suggest a benefit of telbivudine monotherapy for CHB patients with high risk for renal impairment, they do not support the application of telbivudine as a first-line therapy for nucleos(t)ide-na(i)ve HBV patients because of the related high rate of virological resistance.