Abacavir (Ziagen)

Published January 23, 2001; Updated September 12, 2014
Susa Coffey, MD
http://hivinsite.ucsf.edu/InSite?page=ar-01-06
Selected Reference
10. Gulick  RM, Ribaudo  HJ, Shikuma  CM, Lustgarten  S, Squires  KE, Meyer  WA, Acosta  EP, Schackman  BR, Pilcher  CD, Murphy  RL, Maher  WE, Witt  MD, Reichman  RC, Snyder  S, Klingman  KL, Kuritzkes  DR; AIDS Clinical Trials Group Study A5095 Team.
Triple-nucleoside regimens versus efavirenz-containing regimens for the initial treatment of HIV-1 infection. N Engl J Med. 2004 Apr;350(18):1850-61
[PubMed ID: 15115831]
Abstract:
BACKGROUND: Regimens containing three nucleoside reverse-transcriptase inhibitors offer an alternative to regimens containing nonnucleoside reverse-transcriptase inhibitors or protease inhibitors for the initial treatment of human immunodeficiency virus type 1 (HIV-1) infection, but data from direct comparisons are limited. METHODS: This randomized, double-blind study involved three antiretroviral regimens for the initial treatment of subjects infected with HIV-1: zidovudine-lamivudine-abacavir, zidovudine-lamivudine plus efavirenz, and zidovudine-lamivudine-abacavir plus efavirenz. RESULTS: We enrolled a total of 1147 subjects with a mean baseline HIV-1 RNA level of 4.85 log10 (71,434) copies per milliliter and a mean CD4 cell count of 238 per cubic millimeter were enrolled. A scheduled review by the data and safety monitoring board with the use of prespecified stopping boundaries led to a recommendation to stop the triple-nucleoside group and to present the results in the triple-nucleoside group in comparison with pooled data from the efavirenz groups. After a median follow-up of 32 weeks, 82 of 382 subjects in the triple-nucleoside group (21 percent) and 85 of 765 of those in the combined efavirenz groups (11 percent) had virologic failure; the time to virologic failure was significantly shorter in the triple-nucleoside group (P<0.001). This difference was observed regardless of the pretreatment HIV-1 RNA stratum (at least 100,000 copies per milliliter or below this level; P< or =0.001 for both comparisons). Changes in the CD4 cell count and the incidence of grade 3 or grade 4 adverse events did not differ significantly between the groups. CONCLUSIONS: In this trial of the initial treatment of HIV-1 infection, the triple-nucleoside combination of abacavir, zidovudine, and lamivudine was virologically inferior to a regimen containing efavirenz and two or three nucleosides.