title: Comparison of once-daily atazanavir with efavirenz, each in combination with fixed-dose zidovudine and lamivudine, as initial therapy for patients infected with HIV.
abstract: BACKGROUND
  Atazanavir, an azapeptide protease inhibitor (PI), has pharmacokinetics that allow once-daily dosing, and it is not associated with significant PI-associated dyslipidemia.
  
  
  METHODS
  A randomized, double-blind, double-dummy, active-controlled, 2-arm study comparing the antiviral efficacy and safety of atazanavir 400 mg administered once daily with efavirenz 600 mg administered once daily in combination with open-label fixed-dose zidovudine plus lamivudine twice daily. The 810 treatment-naive patients were stratified by HIV RNA level. The primary efficacy end point was the proportion of treated patients with HIV RNA levels <400 copies/mL through week 48.
  
  
  RESULTS
  At week 48, HIV RNA levels were <400 copies/mL in 70% of patients receiving atazanavir and 64% of patients receiving efavirenz (intent-to-treat, difference; 95% confidence interval: 5.2%; -1.2%, 11.7%). Median CD4 cell counts increased at comparable magnitudes and rates in the 2 treatment arms (mean change at week 48: 176 cells/mm with atazanavir, 160 cells/mm with efavirenz). Atazanavir-treated patients relative to comparator-treated patients did not demonstrate significant increases in total cholesterol, fasting low-density lipoprotein cholesterol, or fasting triglycerides over 48 weeks of therapy. Atazanavir-linked bilirubin elevations infrequently resulted in treatment discontinuation (<1%). Atazanavir treatment did not increase fasting glucose or insulin levels.
  
  
  CONCLUSIONS
  For initial HIV treatment, a highly active antiretroviral therapy regimen of atazanavir/zidovudine/lamivudine is as efficacious and well tolerated as the combination of efavirenz/zidovudine/lamivudine.
authors.affiliation: Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Squires
authors.forename: Adriano
authors.initials: A
authors.lastname: Lazzarin
authors.forename: José M
authors.initials: JM
authors.lastname: Gatell
authors.forename: William G
authors.initials: WG
authors.lastname: Powderly
authors.forename: Vadim
authors.initials: V
authors.lastname: Pokrovskiy
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Delfraissy
authors.forename: Joseph
authors.initials: J
authors.lastname: Jemsek
authors.forename: Antonio
authors.initials: A
authors.lastname: Rivero
authors.forename: Willy
authors.initials: W
authors.lastname: Rozenbaum
authors.forename: Shannon
authors.initials: S
authors.lastname: Schrader
authors.forename: Michael
authors.initials: M
authors.lastname: Sension
authors.forename: Asda
authors.initials: A
authors.lastname: Vibhagool
authors.forename: Alexandra
authors.initials: A
authors.lastname: Thiry
authors.forename: Michael
authors.initials: M
authors.lastname: Giordano
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000480:Alkynes; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000009:adverse effects; D023241:Antiretroviral Therapy, Highly Active; D000069446:Atazanavir Sulfate; D048588:Benzoxazines; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000378:metabolism / Q000821:virology; D006801:Humans; D019259:Lamivudine / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides / Q000008:administration & dosage* / Q000009:adverse effects; D010078:Oxazines / Q000008:administration & dosage* / Q000009:adverse effects; D011725:Pyridines / Q000008:administration & dosage* / Q000009:adverse effects; D012367:RNA, Viral / Q000097:blood; D015215:Zidovudine / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D009842:Oligopeptides; D010078:Oxazines; D011725:Pyridines; D012367:RNA, Viral; D019259:Lamivudine; D015215:Zidovudine; D000069446:Atazanavir Sulfate; C098320:efavirenz