title: Simplification of protease inhibitor-containing regimens with efavirenz, nevirapine or abacavir: safety and efficacy outcomes.
abstract: OBJECTIVE
  To describe the immunological and virological outcome, and the factors associated to discontinuation in patients switching to a regimen containing efavirenz (EFV), nevirapine (NVP) or abacavir (ABC) after long-term viral suppression under protease inhibitor-including HAART.
  
  
  METHODS
  Observational study at three outpatient clinics for HIV care in Italy.
  
  
  METHODS
  Patients with HIV RNA <80 copies/ml and CD4 >200 cells/ml for at least 6 months on a protease inhibitor-containing treatment who switched to NVP, EFV or ABC were included in the study. End-points were immunological failure, virological failure and discontinuation due to toxicity. Survival analyses were performed to find out any independent variables predictive of reaching the end-points.
  
  
  RESULTS
  177 patients were enrolled; 85 started EFV, 54 NVP and 38 ABC as part of the simplification regimen. 16/159 patients experienced immunological failure: the variables associated to CD4 count decrease were HIV RNA set point value (HR 2.32 for each log10 copies more, P=0.040) and intolerance/toxicity as reason for simplification (HR 3.96, P=0.05). 13/151 subjects showed virological failure; an AIDS diagnosis (HR 6.04, P=0.021) and the use of NVP (HR 7.98, P=0.027) were associated to a worse virological outcome, while patients naive before HAART showed a lower risk of failure (HR 0.008, P=0.007). 16/177 patients discontinued simplification regimen due to toxicity; longer HAART duration before switch was associated to risk reduction (HR 0.92, P=0.004).
  
  
  CONCLUSIONS
  Simplification is safe and effective, but it should be offered to patients with shorter treatment duration, and in good clinical and immunovirological conditions.
authors.affiliation: Institute of Infectious Diseases and Tropical Medicine, University of Milan, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Chiesa
authors.forename: Teresa
authors.initials: T
authors.lastname: Bini
authors.forename: Fulvio
authors.initials: F
authors.lastname: Adorni
authors.forename: Amedeo
authors.initials: A
authors.lastname: Capetti
authors.forename: Giuliano
authors.initials: G
authors.lastname: Rizzardini
authors.forename: Ivano
authors.initials: I
authors.lastname: Faggion
authors.forename: Cristina
authors.initials: C
authors.lastname: Mussini
authors.forename: Salvatore
authors.initials: S
authors.lastname: Sollima
authors.forename: Sara
authors.initials: S
authors.lastname: Melzi
authors.forename: Marco
authors.initials: M
authors.lastname: Bongiovanni
authors.forename: Federica
authors.initials: F
authors.lastname: Tordato
authors.forename: Paola
authors.initials: P
authors.lastname: Cicconi
authors.forename: Barbara
authors.initials: B
authors.lastname: Castelnuovo
authors.forename: Stefano
authors.initials: S
authors.lastname: Rusconi
authors.forename: Antonella
authors.initials: A
authors.lastname: d'Arminio Monforte
mesh_terms: D000480:Alkynes; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D048588:Benzoxazines; D018791:CD4 Lymphocyte Count; D003521:Cyclopropanes; D015224:Dideoxynucleosides / Q000009:adverse effects / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D017320:HIV Protease Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D015497:HIV-1 / Q000502:physiology; D006801:Humans; D019829:Nevirapine / Q000009:adverse effects / Q000627:therapeutic use*; D010078:Oxazines / Q000009:adverse effects / Q000627:therapeutic use*; D012367:RNA, Viral / Q000097:blood; D012189:Retrospective Studies; D018894:Reverse Transcriptase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome; D000099227:Abacavir
chemical_list: D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D015224:Dideoxynucleosides; D017320:HIV Protease Inhibitors; D019829:Nevirapine; D010078:Oxazines; D012367:RNA, Viral; D018894:Reverse Transcriptase Inhibitors; D000099227:Abacavir; C098320:efavirenz