title: Abacavir/lamivudine versus tenofovir DF/emtricitabine as part of combination regimens for initial treatment of HIV: final results.
abstract: BACKGROUND
  AIDS Clinical Trials Group A5202 compared blinded abacavir/lamivudine (ABC/3TC) to tenofovir DF/emtricitabine (TDF/FTC) with efavirenz (EFV) or atazanavir/ritonavir (ATV/r) in human immunodeficiency virus (HIV)-infected treatment-naive patients, stratified by screening HIV RNA (< or ≥ 10(5) copies/mL). Due to higher virologic failure with ABC/3TC in the high HIV RNA stratum, blinded treatment was stopped in this group, but study follow-up continued for all patients.
  
  
  METHODS
  Primary endpoints were times to virologic failure, regimen modification, and safety event.
  
  
  RESULTS
  In the low HIV RNA stratum, time to virologic failure was similar for ABC/3TC vs TDF/FTC with ATV/r (hazard ratio [HR] 1.25, 95% confidence interval [CI] 0.76, 2.05) or EFV (HR 1.23, 95% CI 0.77, 1.96), with significantly shorter times to regimen modification for ABC/3TC with EFV or ATV/r and to safety events with EFV. Prior to stopping blinded treatment in the high stratum, higher virologic failure rates were seen with ABC/3TC with EFV (HR 2.46, 95% CI 1.20, 5.05) or ATV/r (HR 2.22, 95% CI 1.19, 4.14).
  
  
  CONCLUSIONS
  In the low HIV RNA stratum, times to virologic failure for ABC/3TC or TDF/FTC were not different with EFV or ATV/r. In the high stratum, virologic failure rate was significantly higher for ABC/3TC than for TDF/FTC when given with either EFV or ATV/r.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA. psax@partners.org
authors.forename: Paul E
authors.initials: PE
authors.lastname: Sax
authors.forename: Camlin
authors.initials: C
authors.lastname: Tierney
authors.forename: Ann C
authors.initials: AC
authors.lastname: Collier
authors.forename: Eric S
authors.initials: ES
authors.lastname: Daar
authors.forename: Katie
authors.initials: K
authors.lastname: Mollan
authors.forename: Chakra
authors.initials: C
authors.lastname: Budhathoki
authors.forename: Catherine
authors.initials: C
authors.lastname: Godfrey
authors.forename: Nasreen C
authors.initials: NC
authors.lastname: Jahed
authors.forename: Laurie
authors.initials: L
authors.lastname: Myers
authors.forename: David
authors.initials: D
authors.lastname: Katzenstein
authors.forename: Awny
authors.initials: A
authors.lastname: Farajallah
authors.forename: James F
authors.initials: JF
authors.lastname: Rooney
authors.forename: Belinda
authors.initials: B
authors.lastname: Ha
authors.forename: William C
authors.initials: WC
authors.lastname: Woodward
authors.forename: Judith
authors.initials: J
authors.lastname: Feinberg
authors.forename: Karen
authors.initials: K
authors.lastname: Tashima
authors.forename: Robert L
authors.initials: RL
authors.lastname: Murphy
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Fischl
mesh_terms: D000225:Adenine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods; D018791:CD4 Lymphocyte Count; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015224:Dideoxynucleosides / Q000008:administration & dosage*; D004311:Double-Blind Method; D000068679:Emtricitabine; D005260:Female; D006678:HIV / Q000235:genetics; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D053208:Kaplan-Meier Estimate; D019259:Lamivudine / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D063065:Organophosphonates / Q000008:administration & dosage*; D012367:RNA, Viral / Q000032:analysis / Q000097:blood; D000068698:Tenofovir; D019562:Viral Load; D000099227:Abacavir
chemical_list: D000225:Adenine; D019380:Anti-HIV Agents; D003841:Deoxycytidine; D015224:Dideoxynucleosides; D000068679:Emtricitabine; D019259:Lamivudine; D063065:Organophosphonates; D012367:RNA, Viral; D000068698:Tenofovir; D000099227:Abacavir