Clin Mol Hepatol.  2016 Jun;22(2):241-249. 10.3350/cmh.2015.0053.

The efficacy of tenofovir-based therapy in patients showing suboptimal response to entecavir-adefovir combination therapy

• Kim JH
• Ahn SH
• Ko SY
• Choe WH
• Kim KH
• Kwon SY

• KMID: 2373120
• DOI: http://doi.org/10.3350/cmh.2015.0053

Abstract

BACKGROUND/AIMS
Before tenofovir (TDF) become available in South Korea, combination therapy with entecavir (ETV) and adefovir (ADV) was the most potent regimen for chronic hepatitis B (CHB) patients who fail to respond to rescue therapy for drug resistance. We analyzed the efficacy of ETV-ADV combination therapy and investigated the clinical and clonal results of TDF-based rescue therapy in CHB patients refractory to this combination.
METHODS
We retrospectively reviewed the medical records of CHB patients treated for up to 3 years with ETV-ADV combination therapy as a rescue therapy for drug resistance. In cases refractory to this combination, clinical and clonal analyses were performed for TDF-based rescue therapy.
RESULTS
The analysis was performed on 48 patients. Twelve patients achieved a virological response (VR) within 3 years. A VR was subsequently achieved in nine of the ten patients without a VR who switched to TDF monotherapy. A VR was also achieved in six of the seven patients who switched to lamivudine-TDF combination therapy, and in two of the two patients who switched to ETV-TDF combination therapy. In an in vitro susceptibility test, viral replication was detected with TDF monotherapy but not with ETV-TDF combination therapy.
CONCLUSIONS
The efficacy of ETV-ADV combination therapy was insufficient in CHB patients who were refractory to rescue therapy. A more potent regimen such as ETV-TDF combination therapy may be considered in such refractory cases.

Keyword

Chronic Hepatitis B; Entecavir; Adefovir; Lamivudine; Tenofovir; Resistance

MeSH Terms

Adenine/*analogs & derivatives/therapeutic use
Adult
Aged
Antiviral Agents/*therapeutic use
DNA, Viral/analysis/metabolism
Drug Resistance, Viral
Drug Therapy, Combination
Female
Guanine/*analogs & derivatives/therapeutic use
Hepatitis B virus/genetics/isolation & purification
Hepatitis B, Chronic/*drug therapy/virology
Humans
Male
Middle Aged
Organophosphonates/*therapeutic use
Polymerase Chain Reaction
Republic of Korea
Retrospective Studies
Tenofovir/*therapeutic use
Treatment Outcome
Adenine
Antiviral Agents
DNA, Viral
Guanine
Organophosphonates
Tenofovir