title: Durable efficacy of tipranavir-ritonavir in combination with an optimised background regimen of antiretroviral drugs for treatment-experienced HIV-1-infected patients at 48 weeks in the Randomized Evaluation of Strategic Intervention in multi-drug reSistant patients with Tipranavir (RESIST) studies: an analysis of combined data from two randomised open-label trials.
abstract: BACKGROUND
  Treatment options for HIV-1 infected individuals who have received extensive previous antiretroviral therapy are limited. We compared efficacy and safety of the novel non-peptidic protease inhibitor tipranavir co-administered with ritonavir plus an optimised background regimen with that of an investigator-selected ritonavir-boosted comparator protease inhibitor (CPI-ritonavir) in such patients.
  
  
  METHODS
  We did a combined analysis of 48-week data from two ongoing, randomised, open-label, multinational, phase III, RESIST studies. HIV-1-infected adults with 3 months or longer previous triple antiretroviral class experience, two or more previous protease inhibitor regimens, HIV-1 RNA 1000 copies per mL or greater, and genotypically demonstrated primary resistance to protease inhibitor, were eligible. Primary endpoints were proportion of treatment responders (with reduction in viral load of 1 log(10) copies per mL or greater below baseline without treatment change) at 48 weeks and time to treatment failure through 48 weeks (intention-to-treat analysis). The RESIST studies are registered with ClinicalTrials.gov, numbers NCT00054717 (RESIST-1) and NCT00144170 (RESIST-2).
  
  
  RESULTS
  3324 patients were screened; 746 received tipranavir-ritonavir and 737 CPI-ritonavir. 486 (65.1%) patients on tipranavir-ritonavir and 192 (26.1%) on CPI-ritonavir remained on assigned treatment until week 48. At week 48, more patients achieved and maintained treatment response in the tipranavir-ritonavir group than in the CPI-ritonavir group (251 [33.6%] vs 113 [15.3%]; p<0.0001). Median time to treatment failure was significantly longer in the tipranavir-ritonavir group than in the CPI-ritonavir group (113 days vs 0 days; p<0.0001). Gastrointestinal system disorders and raised transaminase, cholesterol, and triglycerides were more frequent in the tipranavir-ritonavir group than in the CPI-ritonavir group.
  
  
  CONCLUSIONS
  Compared with CPI-ritonavir, tipranavir-ritonavir with an optimised background regimen provides better virological and immunological responses over 48 weeks in patients who have received extensive previous antiretroviral treatment.
authors.affiliation: Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, NC 27710, USA. charles.hicks@duke.edu
authors.forename: Charles B
authors.initials: CB
authors.lastname: Hicks
authors.forename: Pedro
authors.initials: P
authors.lastname: Cahn
authors.forename: David A
authors.initials: DA
authors.lastname: Cooper
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Walmsley
authors.forename: Christine
authors.initials: C
authors.lastname: Katlama
authors.forename: Bonaventura
authors.initials: B
authors.lastname: Clotet
authors.forename: Adriano
authors.initials: A
authors.lastname: Lazzarin
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Johnson
authors.forename: Dietmar
authors.initials: D
authors.lastname: Neubacher
authors.forename: Douglas
authors.initials: D
authors.lastname: Mayers
authors.forename: Hernan
authors.initials: H
authors.lastname: Valdez
mesh_terms: D000328:Adult; D024882:Drug Resistance, Viral / Q000235:genetics; D004359:Drug Therapy, Combination; D000077560:Enfuvirtide; D005260:Female; D015700:HIV Envelope Protein gp41 / Q000627:therapeutic use; D023581:HIV Fusion Inhibitors / Q000627:therapeutic use; D015658:HIV Infections / Q000188:drug therapy*; D017320:HIV Protease Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D016015:Logistic Models; D008297:Male; D015337:Multicenter Studies as Topic; D010446:Peptide Fragments / Q000627:therapeutic use; D011725:Pyridines / Q000008:administration & dosage / Q000627:therapeutic use*; D011753:Pyrones / Q000008:administration & dosage / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic; D019438:Ritonavir / Q000008:administration & dosage / Q000627:therapeutic use*; D013449:Sulfonamides; D013997:Time Factors; D017211:Treatment Failure; D019562:Viral Load
chemical_list: D015700:HIV Envelope Protein gp41; D023581:HIV Fusion Inhibitors; D017320:HIV Protease Inhibitors; D010446:Peptide Fragments; D011725:Pyridines; D011753:Pyrones; D013449:Sulfonamides; D000077560:Enfuvirtide; D019438:Ritonavir; C107201:tipranavir