Boosted lopinavir- versus boosted atazanavir-containing regimens and immunologic, virologic, and clinical outcomes: a prospective study of HIV-infected individuals in high-income countries

Clin Infect Dis. 2015 Apr 15;60(8):1262-8. doi: 10.1093/cid/ciu1167. Epub 2015 Jan 6.

Abstract

Background: Current clinical guidelines consider regimens consisting of either ritonavir-boosted atazanavir or ritonavir-boosted lopinavir and a nucleoside reverse transcriptase inhibitor (NRTI) backbone among their recommended and alternative first-line antiretroviral regimens. However, these guidelines are based on limited evidence from randomized clinical trials and clinical experience.

Methods: We compared these regimens with respect to clinical, immunologic, and virologic outcomes using data from prospective studies of human immunodeficiency virus (HIV)-infected individuals in Europe and the United States in the HIV-CAUSAL Collaboration, 2004-2013. Antiretroviral therapy-naive and AIDS-free individuals were followed from the time they started a lopinavir or an atazanavir regimen. We estimated the 'intention-to-treat' effect for atazanavir vs lopinavir regimens on each of the outcomes.

Results: A total of 6668 individuals started a lopinavir regimen (213 deaths, 457 AIDS-defining illnesses or deaths), and 4301 individuals started an atazanavir regimen (83 deaths, 157 AIDS-defining illnesses or deaths). The adjusted intention-to-treat hazard ratios for atazanavir vs lopinavir regimens were 0.70 (95% confidence interval [CI], .53-.91) for death, 0.67 (95% CI, .55-.82) for AIDS-defining illness or death, and 0.91 (95% CI, .84-.99) for virologic failure at 12 months. The mean 12-month increase in CD4 count was 8.15 (95% CI, -.13 to 16.43) cells/µL higher in the atazanavir group. Estimates differed by NRTI backbone.

Conclusions: Our estimates are consistent with a lower mortality, a lower incidence of AIDS-defining illness, a greater 12-month increase in CD4 cell count, and a smaller risk of virologic failure at 12 months for atazanavir compared with lopinavir regimens.

Keywords: HIV; atazanavir; lopinavir; mortality; observational studies.

Publication types

  • Observational Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anti-HIV Agents / therapeutic use*
  • Antiretroviral Therapy, Highly Active / methods*
  • Atazanavir Sulfate / therapeutic use*
  • CD4 Lymphocyte Count
  • Cohort Studies
  • Cooperative Behavior
  • Developed Countries
  • Europe
  • Female
  • HIV Infections / drug therapy*
  • HIV Infections / immunology
  • HIV Infections / virology
  • Humans
  • Lopinavir / therapeutic use*
  • Male
  • Middle Aged
  • Prospective Studies
  • Treatment Outcome
  • United States
  • Viral Load
  • Young Adult

Substances

  • Anti-HIV Agents
  • Lopinavir
  • Atazanavir Sulfate