Long-term Adefovir (Hepsera) plus Emtricitabine (Emtriva) vs Adefovir Monotherapy
for Chronic Hepatitis B
Antiviral
therapy with nucleoside/nucleotide analog agents is effective against chronic
hepatitis B virus (HBV) infection, but long-term efficacy is limited by the
emergence of drug resistant virus.
As reported in the May 2008 Journal
of Hepatology, researchers from the University of Hong Kong conducted a trial
to determine the efficacy of adefovir dipivoxil (Hepsera)
plus emtricitabine
(Emtriva) combination therapy in patients with chronic hepatitis B. Adefovir
is currently approved for this indication; emtricitabine is approved for the treatment
of HIV, but is still under investigation for HBV.
In this study, 30 previously
untreated hepatitis B "e" antigen (HBeAg) positive patients were randomly
assigned to either combination adefovir plus emtricitabine (n=14) or adefovir
monotherapy (n=16) for 96 weeks. HBV DNA was measured by polymerase chain reaction.
Treatment was stopped in those who achieved HBeAg seroconversion.
Results
•
At 96 weeks, the median decrease in HBV DNA was greater in the combination therapy
group compared with the adefovir monotherapy group (5.30 vs 3.98 log10 copies/mL;
P = 0.05).
•
More patients in the combination therapy group achieved alanine aminotransferase
(ALT) normalization and HBV DNA < 300 copies/mL compared with the monotherapy
group (78.6% vs 37.5%; P = 0.03).
•
However, the rate of HBeAg seroconversion at week 96 was similar in the 2 groups
(14.3% vs 25.0%; P = non-significant).
•
No adefovir or emtricitabine resistance was detected at week 96.
•
Among patients with HBeAg seroconversion, 50.0% experienced post-treatment relapse.
Conclusion
Based
on these findings, the study authors concluded, "Combination [adefovir] plus
[emtricitabine] resulted in more potent suppression of HBV DNA over 96 weeks of
therapy."
4/18/08
Reference C-K Hui, H-Y Zhang, S
Bowden, and others. 96 weeks combination of adefovir dipivoxil plus emtricitabine
vs. adefovir dipivoxil monotherapy in the treatment of chronic hepatitis B. Journal
of Hepatology 48(5): 714-720. May 2008.
FDA-approved
Treatments
Results
