title: Dual therapy based on a ritonavir-boosted protease inhibitor as a novel salvage strategy for HIV-1-infected patients on a failing antiretroviral regimen.
abstract: OBJECTIVE
  To assess the efficacy and safety of dual-antiretroviral therapy containing a ritonavir-boosted protease inhibitor (PI/r) in treatment-experienced patients failing a current antiretroviral regimen.
  
  
  METHODS
  Retrospective analysis of 60 consecutive HIV-1-infected patients who started a dual-antiretroviral rescue regimen containing a PI/r, in three hospitals in Spain. Virological failure was defined as confirmed HIV RNA >50 copies/mL at treatment week 24 or later. The percentage of patients remaining free of therapeutic failure was estimated using the Kaplan-Meier method, by intent-to-treat analysis (missing, changes and virological failure = therapeutic failure).
  
  
  RESULTS
  Median baseline characteristics of patients were: 13 years on antiretroviral therapy (four prior highly active antiretroviral therapy regimens and eight different drugs), 380 CD4 cells/mm(3) and HIV RNA 3.04 log(10) copies/mL. All patients had resistance mutations to at least two drug classes, although only 9.3% had specific mutations to darunavir. A darunavir-based regimen was started in 47 (78.4%) patients, combined with etravirine (26.7%), tenofovir (26.7%) or raltegravir (25%). Three (5%) patients discontinued treatment due to side effects. At the end of follow-up, 86.7% of patients remained free of therapeutic failure; the percentages of patients with no therapeutic failure at treatment weeks 24, 48 and 96 were 96.6% (95% CI, 91.9-101.3); 90.1% (95% CI, 81.9-98.3) and 79.8% (95% CI, 66.1-93.5), respectively.
  
  
  CONCLUSIONS
  Our results suggest that a dual-therapy rescue regimen including a PI/r is convenient, well tolerated and potent enough to achieve persistent viral suppression in selected pre-treated patients with low viral load and few PI resistance mutations.
authors.affiliation: Department of Infectious Diseases, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain. jburgos@vhebron.net
authors.forename: Joaquin
authors.initials: J
authors.lastname: Burgos
authors.forename: Manuel
authors.initials: M
authors.lastname: Crespo
authors.forename: Vicenç
authors.initials: V
authors.lastname: Falcó
authors.forename: Adria
authors.initials: A
authors.lastname: Curran
authors.forename: Arkaitz
authors.initials: A
authors.lastname: Imaz
authors.forename: Pere
authors.initials: P
authors.lastname: Domingo
authors.forename: Daniel
authors.initials: D
authors.lastname: Podzamczer
authors.forename: Maria Gracia
authors.initials: MG
authors.lastname: Mateo
authors.forename: Eva
authors.initials: E
authors.lastname: Van den Eynde
authors.forename: Sara
authors.initials: S
authors.lastname: Villar
authors.forename: Esteve
authors.initials: E
authors.lastname: Ribera
mesh_terms: D000328:Adult; D023241:Antiretroviral Therapy, Highly Active / Q000009:adverse effects / Q000379:methods; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D017320:HIV Protease Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D019438:Ritonavir / Q000008:administration & dosage* / Q000009:adverse effects; D016879:Salvage Therapy / Q000009:adverse effects / Q000379:methods*; D013030:Spain; D016896:Treatment Outcome; D019562:Viral Load
chemical_list: D017320:HIV Protease Inhibitors; D019438:Ritonavir