1Department of Internal Medicine, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Republic of Korea.
2Biomedical Research Center, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Republic of Korea.
BACKGROUND AND AIM:
In the past decade, many chronic hepatitis B (CHB) patients have undergone sequential treatment with lamivudine (LAM), adefovir (ADV), and entecavir (ETV) to manage antiviral resistance or insufficient suppression of HBV DNA. Very limited data are available on the efficacy of Tenofovir (TDF) rescue regimens in patients with multi-drug resistance (MDR).
We investigated the antiviral efficacy of TDF/LAM combination therapy versus TDF/ETV combination therapy in 52 patients who failed three previous antiviral therapies.
The study subjects were treated with TDF/LAM combination therapy (n=25) or TDF/ETV combination therapy (n=27) for more than 6 months. Virologic response (VR) occurred in 39 (75%) patients (19 patients belonged to the TDF/LAM group and 20 patients belonged to the TDF/ETV group). The VR rates were not different between the TDF/LAM and TDF/ETV groups (56.0% vs. 51.9% at month 12, and 72.0% vs. 78.8% at month 18; log rank P=0.515). In addition, treatment efficacy of TDF/LAM combination or TDF/ETV combination was not statistically different according to types of MDR. In multivariate analysis, absolute HBV DNA level at the start of TDF rescue treatment (P<0.001; OR, 0.452; 95% CI, 0.306-0.666) was only significantly associated with VR.
TDF/ETV combination therapy was not associated with higher rate of VR compared with TDF/LAM combination therapy in MDR CHB patients. These results raise the suspicion about the superiority of the combination therapy over TDF monotherapy. The lower HBV DNA levels at the start of TDF-based rescue therapy were associated with higher VR.