Immunovirological response to triple nucleotide reverse-transcriptase inhibitors and ritonavir-boosted protease inhibitors in treatment-naive HIV-2-infected patients: The ACHIEV2E Collaboration Study Group

Clin Infect Dis. 2011 May;52(10):1257-66. doi: 10.1093/cid/cir123.


Background: Triple nucleoside reverse-transcriptase inhibitors (NRTIs) are recommended by the World Health Organization as first-line regimen in treatment-naïve HIV-2-infected patients. However, ritonavir-boosted protease inhibitor (PI/r)-containing regimens are frequently prescribed. In the absence of previous randomized trials, we retrospectively compared these regimens in observational cohorts.

Methods: HIV-2-infected patients from 7 European cohorts who started triple NRTI or PI/r since January 1998 were included. Piecewise linear models were used to estimate CD4 cell count and plasma HIV-2 RNA level slopes, differentiating an early phase (until end of month 3) and a second phase (months 4-12). On-treatment analyses censored data at major treatment modification and systematically at month 12.

Results: Forty-four patients started triple NRTI therapy and 126 started PI/r therapy. Overall, the median CD4 cell count was 191 cells/mm(3) and the median plasma HIV-2 RNA level was ≥2.7 log(10) copies/ml in 61% of the patients at combination antiretroviral therapy (cART) initiation; the median duration of the first cART was 20 months, not differing between groups. PI/r regimens were associated with better CD4 cell count and HIV-2 RNA level outcomes, compared with NRTI regimens. Estimated CD4 cell count slopes were +6 and +12 cells/mm(3)/month during the early phase (P = .22), and -60 cells/mm(3)/year versus +76 cells/mm(3)/year during the second phase (P = .002), for triple NRTI and PI/r, respectively. Estimated mean HIV-2 RNA levels at month 12 in patients with detectable viremia at cART initiation were 4.0 and 2.2 log(10) copies/ml, respectively (P = .005).

Conclusions: In this observational study, PI/r-containing regimens showed superior efficacy over triple NRTI regimens as first-line therapy in HIV-2-infected patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-HIV Agents / administration & dosage*
  • CD4 Lymphocyte Count
  • Europe
  • HIV Infections / drug therapy*
  • HIV Infections / virology
  • HIV Protease Inhibitors / administration & dosage*
  • HIV-2 / isolation & purification*
  • Humans
  • RNA, Viral / blood
  • Retrospective Studies
  • Reverse Transcriptase Inhibitors / administration & dosage*
  • Ritonavir / administration & dosage*
  • Treatment Outcome
  • Viral Load


  • Anti-HIV Agents
  • HIV Protease Inhibitors
  • RNA, Viral
  • Reverse Transcriptase Inhibitors
  • Ritonavir