title: Ritonavir plus saquinavir versus single protease inhibitor therapy in protease inhibitor-naive HIV-infected patients: the Swiss HIV Cohort Study.
abstract: OBJECTIVE
  To compare the response to ritonavir (RTV) plus saquinavir (SQV) with single protease inhibitor (PI) therapies among PI-naive HIV-1 infected individuals.
  
  
  METHODS
  Response to treatment was analysed according to the intent-to-treat principle in a prospective observational cohort study of 177 patients who between May 1995 and March 2000 started a double PI therapy with RTV and SQV (nonboosting dosages) plus at least one nucleoside reverse transcriptase inhibitor (NRTI) and 2,214 patients with a single PI therapy plus two NRTIs. We used survival analysis and Cox's proportional hazard regression methods. The primary endpoint was the time to a plasma viral load of < 400 copies/mL. Secondary endpoints were taken as a gain in the CD4 count of >100 cells/microL, and change of initial PI for any reason.
  
  
  RESULTS
  Baseline characteristics in both treatment groups were balanced. Median follow-up in both groups was 10.4 months. Time to an HIV-1 viral load of < 400 copies/mL and an increase in the CD4 count of >100 x 10(6) cells/L was shorter for RTV plus SQV compared with single PI regimens (log rank test for each endpoint P < 0.05). The adjusted hazard ratios of RTV plus SQV compared with single PI regimens were 1.21 (95% confidence interval 0.99-1.47) for achieving an HIV-1 viral load of < 400 copies/mL, 1.12 (0.88-1.42) for an increase in the CD4 count of > 100 cells/microL, and 0.90 (0.73-1.11) for change of first PI regimen.
  
  
  CONCLUSIONS
  Treatment with RTV plus SQV compared with single PI regimens appeared to give similar results for virological or immunological response.
authors.affiliation: Basel Center for HIV Research, Internal Medicine Outpatient Clinic University Hospital Basel, Switzerland. hbucher@uhbs.ch
authors.forename: H C
authors.initials: HC
authors.lastname: Bucher
authors.forename: M
authors.initials: M
authors.lastname: Bichsel
authors.forename: P
authors.initials: P
authors.lastname: Taffé
authors.forename: H
authors.initials: H
authors.lastname: Furrer
authors.forename: A
authors.initials: A
authors.lastname: Telenti
authors.forename: B
authors.initials: B
authors.lastname: Hirschel
authors.forename: R
authors.initials: R
authors.lastname: Weber
authors.forename: E
authors.initials: E
authors.lastname: Bernasconi
authors.forename: P
authors.initials: P
authors.lastname: Vernazza
authors.forename: C
authors.initials: C
authors.lastname: Minder
authors.forename: M
authors.initials: M
authors.lastname: Battegay
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000188:drug therapy*; D017320:HIV Protease Inhibitors / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood; D018894:Reverse Transcriptase Inhibitors / Q000008:administration & dosage*; D019438:Ritonavir / Q000008:administration & dosage*; D019258:Saquinavir / Q000008:administration & dosage*; D019562:Viral Load
chemical_list: D017320:HIV Protease Inhibitors; D012367:RNA, Viral; D018894:Reverse Transcriptase Inhibitors; D019258:Saquinavir; D019438:Ritonavir