title: Durability of lopinavir/ritonavir monotherapy in individuals with viral load ≤50 copies/ml in an observational setting.
abstract: BACKGROUND
  The main objective is to evaluate the efficacy and durability of lopinavir-ritonavir monotherapy (LPV/r-MT) in virologically controlled HIV-positive individuals switching from combination antiretroviral therapy (cART).
  
  
  METHODS
  Criteria to be included in this observational study were to have initiated for the first time LPV/r-MT after ≥2 consecutive HIV RNA≤50 copies/ml achieved on a ≥3-drug-including regimen. The main end points were time to virological rebound (VR; defined in two ways: time of first of two consecutive viral load [VL]>50 and >200 copies/ml), time to discontinuation/intensification and time to experience either a single VL>200 copies/ml or discontinuation/intensification (treatment failure [TF]). Individuals' follow-up accrued from the date of starting LPV/r-MT to event or last available VL. Kaplan-Meier curves and Cox regression analyses were used.
  
  
  RESULTS
  A total of 228 individuals were included: median age 46 years (IQR 40-50), 36% females, 36% intravenous drug users and 25% HCV-coinfected. Median CD4(+) T-cell count at nadir was 215 cell/mm(3) (IQR 116-336) and at baseline was 615 cell/mm(3) (IQR 436-768). By 36 months after switching to LPV/r-MT, the proportion of individuals with VR (confirmed VL>200 copies/ml) was 11% and with TF was 35%. In the multivariable Cox model the factors associated with a lower risk of TF was the duration of viral suppression <50 copies/ml prior to baseline (ARH=0.92; 95% CI 0.85, 0.99; P=0.024, per 6 months longer) and having LPV/r as part of last cART (ARH=0.45; 95% CI 0.21, 0.95; P=0.037).
  
  
  CONCLUSIONS
  In daily clinical practice, we confirm a relatively safe approach of treatment simplification to LPV-MT in a selected population with long-lasting virological control.
authors.affiliation: Department of Health Sciences, Institute of Infectious Diseases, University of Milan, Milan, Italy. antonella.darminio@unimi.it.
authors.forename: Antonella
authors.initials: A
authors.lastname: d'Arminio Monforte
authors.forename: Nicola
authors.initials: N
authors.lastname: Gianotti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cozzi-Lepri
authors.forename: Carmela
authors.initials: C
authors.lastname: Pinnetti
authors.forename: Massimo
authors.initials: M
authors.lastname: Andreoni
authors.forename: Giovanni
authors.initials: G
authors.lastname: di Perri
authors.forename: Massimo
authors.initials: M
authors.lastname: Galli
authors.forename: Andrea
authors.initials: A
authors.lastname: Poli
authors.forename: Andrea
authors.initials: A
authors.lastname: Costantini
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Orofino
authors.forename: Franco
authors.initials: F
authors.lastname: Maggiolo
authors.forename: Giovanni
authors.initials: G
authors.lastname: Mazzarello
authors.forename: Benedetto Maurizio
authors.initials: BM
authors.lastname: Celesia
authors.forename: Filippo
authors.initials: F
authors.lastname: Luciani
authors.forename: Adriano
authors.initials: A
authors.lastname: Lazzarin
authors.forename: Laura
authors.initials: L
authors.lastname: Sighinolfi
authors.forename: Giuliano
authors.initials: G
authors.lastname: Rizzardini
authors.forename: Paolo
authors.initials: P
authors.lastname: Bonfanti
authors.forename: Carlo Federico
authors.initials: CF
authors.lastname: Perno
authors.forename: Andrea
authors.initials: A
authors.lastname: Antinori
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1 / Q000187:drug effects* / Q000502:physiology; D016174:Hepacivirus / Q000502:physiology; D006526:Hepatitis C / Q000150:complications / Q000188:drug therapy / Q000821:virology; D006801:Humans; D061466:Lopinavir / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood*; D019438:Ritonavir / Q000627:therapeutic use*; D019966:Substance-Related Disorders / Q000150:complications / Q000821:virology; D013997:Time Factors; D019562:Viral Load / Q000187:drug effects
chemical_list: D019380:Anti-HIV Agents; D012367:RNA, Viral; D061466:Lopinavir; D019438:Ritonavir