title: Switch from a first virologically effective protease inhibitor-containing regimen to a regimen containing efavirenz, nevirapine or abacavir.
abstract: BACKGROUND
  Treatment simplification in antiretroviral-experienced patients receiving protease inhibitor (PI)-containing antiretroviral regimens seems safe, but randomized trials have limited power to detect differences in virological rebound (VR) between different switch strategies.
  
  
  METHODS
  From the French Hospital Database on HIV, we selected 2462 patients with undetectable viral load (VL) who switched from a first PI-containing antiretroviral combination (cART) to a combination containing efavirenz (EFV), nevirapine (NVP) or abacavir (ABC). Factors associated with VR and with immunological efficacy (gain of > or = 50 CD4(+) cells/microl) were identified by using Cox models.
  
  
  RESULTS
  The 12-month Kaplan-Meier probabilities of VR were 6.8, 13.7 and 12.3% in patients switching to EFV-cART, NVP-cART and ABC-cART, respectively. Factors associated with VR were female sex, younger age, antiretroviral exposure before the first cART, time on first cART, higher VL at first cART initiation, a stavudine/didanosine backbone (rather than zidovudine/lamivudine) after the switch, and a switch to NVP or ABC [respective adjusted hazard ratio versus EFV: 1.53; 95% confidence interval (CI), 1.21-1.94; and 1.53; 95% CI, 1.12-2.08]. When the analyses were restricted to patients who were antiretroviral-naive before their first cART, NVP (but not ABC) was associated with VR. Immunological outcomes did not differ among the three switch regimens.
  
  
  CONCLUSIONS
  When VL is undetectable on a first PI-cART regimen, switching to an EFV-containing regimen is more likely to avoid VR than switching to an ABC or NVP-containing regimen. ABC may be an alternative to EFV for patients who were not exposed to antiretroviral before their first cART regimen, after checking for ABC resistance mutations.
authors.affiliation: INSERM U720, Paris, France. sophie.abgrall@ccde.chups.jussieu.fr
authors.forename: Sophie
authors.initials: S
authors.lastname: Abgrall
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Yeni
authors.forename: Olivier
authors.initials: O
authors.lastname: Bouchaud
authors.forename: Dominique
authors.initials: D
authors.lastname: Costagliola
mesh_terms: D000328:Adult; D000480:Alkynes; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D048588:Benzoxazines; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D015224:Dideoxynucleosides / Q000627:therapeutic use; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D017320:HIV Protease Inhibitors / Q000627:therapeutic use; D015497:HIV-1; D006801:Humans; D008297:Male; D008875:Middle Aged; D019829:Nevirapine / Q000627:therapeutic use; D010078:Oxazines / Q000627:therapeutic use; D011446:Prospective Studies; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use; D012307:Risk Factors; D016896:Treatment Outcome; D019562:Viral Load; D000099227:Abacavir
chemical_list: D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D015224:Dideoxynucleosides; D017320:HIV Protease Inhibitors; D019829:Nevirapine; D010078:Oxazines; D018894:Reverse Transcriptase Inhibitors; D000099227:Abacavir; C098320:efavirenz