OBJECTIVES: To assess the clinical utility of phenotypic resistance testing in addition to genotypic resistance testing among HIV-1-infected patients experiencing virologic failure and with limited therapeutic options. DESIGN: Multicenter randomized trial. METHODS:Patients were eligible if a decision had been made to switch antiretroviral therapy, the most recent HIV-1 RNA plasma viral load (VL) exceeded 2000 copies/mL, and the clinician was unable to select a potent regimen of 3 or more drugs without access to a resistance test. Subjects were randomized to genotypic resistance testing alone (G arm) or to genotypic plus phenotypic testing (G + P arm). Patients had access to resistance testing at any time during follow-up (minimum of 1 year) according to the original allocation. The primary end point was change in plasma VL from baseline at 12 months. RESULTS:Three hundred eleven patients were recruited between February 2000 and July 2001. At baseline, mean VL and CD4 count were 4.23 log10 copies/mL and 275 cells/mm, respectively, and subjects had previous exposure to a mean of 7.7 antiretroviral drugs. There was no appreciable difference between the study arms in the drug regimens prescribed after randomization. Mean reduction in VL load at 12 months was similar in the 2 arms (G: 1.37 log10 reduction, G + P: 1.28 log10 reduction; P = 0.77), as was the proportion of subjects with VL <50 copies/mL (G: 35%, G + P: 27%). CONCLUSION: The study did not demonstrate added value of phenotypic resistance testing in conjunction with genotypic resistance testing in patients with limited therapeutic options.
RCT Entities:
OBJECTIVES: To assess the clinical utility of phenotypic resistance testing in addition to genotypic resistance testing among HIV-1-infectedpatients experiencing virologic failure and with limited therapeutic options. DESIGN: Multicenter randomized trial. METHODS:Patients were eligible if a decision had been made to switch antiretroviral therapy, the most recent HIV-1 RNA plasma viral load (VL) exceeded 2000 copies/mL, and the clinician was unable to select a potent regimen of 3 or more drugs without access to a resistance test. Subjects were randomized to genotypic resistance testing alone (G arm) or to genotypic plus phenotypic testing (G + P arm). Patients had access to resistance testing at any time during follow-up (minimum of 1 year) according to the original allocation. The primary end point was change in plasma VL from baseline at 12 months. RESULTS: Three hundred eleven patients were recruited between February 2000 and July 2001. At baseline, mean VL and CD4 count were 4.23 log10 copies/mL and 275 cells/mm, respectively, and subjects had previous exposure to a mean of 7.7 antiretroviral drugs. There was no appreciable difference between the study arms in the drug regimens prescribed after randomization. Mean reduction in VL load at 12 months was similar in the 2 arms (G: 1.37 log10 reduction, G + P: 1.28 log10 reduction; P = 0.77), as was the proportion of subjects with VL <50 copies/mL (G: 35%, G + P: 27%). CONCLUSION: The study did not demonstrate added value of phenotypic resistance testing in conjunction with genotypic resistance testing in patients with limited therapeutic options.
Authors: Philip Grant; Eric C Wong; Richard Rode; Robert Shafer; Andrea De Luca; Jeffrey Nadler; Trevor Hawkins; Calvin Cohen; Robert Harrington; Dale Kempf; Andrew Zolopa Journal: Antimicrob Agents Chemother Date: 2008-08-18 Impact factor: 5.191
Authors: Jan Fehr; Tracy R Glass; Séverine Louvel; François Hamy; Hans H Hirsch; Viktor von Wyl; Jürg Böni; Sabine Yerly; Philippe Bürgisser; Matthias Cavassini; Christoph A Fux; Bernard Hirschel; Pietro Vernazza; Gladys Martinetti; Enos Bernasconi; Huldrych F Günthard; Manuel Battegay; Heiner C Bucher; Thomas Klimkait Journal: J Transl Med Date: 2011-01-21 Impact factor: 5.531