Tenofovir plus Lamivudine versus Tenofovir after Lamivudine Failure in HIV-HBV
Coinfected Patients By
Liz Highleyman Treatment
for chronic hepatitis B is limited by the emergence of resistance
to lamivudine (Epivir), the most common first-line antiviral drug. Patients
who develop lamivudine resistance are often subsequently treated with a newer
agent, such as adefovir (Hepsera) or tenofovir
(Viread). However, lessons learned in the management of HIV suggest that simultaneous
use of two or more drugs could help delay resistance and treatment failure.
In the present study, reported in the October 3, 2006 issue of AIDS,
an international team of investigators conducted a multicenter trial to assess
whether starting treatment with 2 agents active against HBV produces better outcomes
than sequential anti-HBV therapy. Both lamivudine and tenofovir are active against
HBV as well as HIV; however, tenofovir is not yet approved for hepatitis B treatment. The
researchers performed a 1:2 matched-pair analysis comparing HIV-HBV
coinfected patients starting antiretroviral regimens that included tenofovir
plus lamivudine, against patients who had highly replicative, HBe-antigen (HBeAg)
positive HBV that was already resistant to lamivudine (and for whom, therefore,
tenofovir was the only active anti-HBV drug in the regimen). Results 
At baseline, the 25 patients on first-line tenofovir plus lamivudine regimens
had a median HBV DNA level of 5.9 x 10 copies/mL, compared to 1.37 x 10 copies/mL
for the 50 lamivudine-resistant patients (P = 0.32).
After a median treatment period of 116 weeks, 19 out of 25 patients (76%) on first-line
tenofovir plus lamivudine achieved sustained undetectable HBV DNA (below 1000
copies/mL), compared with 42 out of 50 (84%) in the lamivudine-resistant group
(P = 0.53).
HBeAg loss was observed in 9 of 25 patients (36%) on first-line tenofovir plus
lamivudine, compared with 12 of 50 (24%) lamivudine-resistance subjects (P = 0.29).
HB surface antigen (HBsAg) loss was observed in 1 of 25 (4%) and 3 of 50 (6%)
patients in the two groups, respectively.
Conclusion "In
this cohort of HBV-HIV coinfected individuals, full HBV DNA suppression was achieved
in the majority of patients independent of treatment allocation," the authors
concluded. They added that loss of HBeAg and HBsAg also "was not different
between the two study arms." They
noted that over a median treatment period of 116 weeks (about 2 years), tenofovir
as the sole active anti-HBV drug was as effective as first-line tenofovir plus
lamivudine. However, the suggested, "Longer treatment periods may be needed
to evaluate potential benefits of first-line combination therapy for chronic hepatitis
B," since it takes time for HBV resistance to emerge. Center
for HIV and Hepatogastroenterology, Duesseldorf, Germany; Kobler Clinic, Chelsea
and Westminster Hospital, London, UK; HIV-cohort Frankfurt, Germany; Hospital
Carlos III, Madrid, Spain; San Matteo Hospital, University of Pavia, Italy; Medizinische
Klinik Charite, Berlin, Germany; Institute for Interdisciplinary Infectiology
and Immunology, Hamburg, Germany; Med. Klinik I, Universitaetsklinikum Bonn, Germany;
MUC Research, Munich, Germany. 10/13/06 Reference
G
Schmutz, M Nelson, T Lutz, and others. Combination of tenofovir and lamivudine
versus tenofovir after lamivudine failure for therapy of hepatitis B in HIV-coinfection.
AIDS 20(15): 1951-1954. October 3, 2006. | |
