title: Unexpected drug-drug interaction between tipranavir/ritonavir and enfuvirtide.
abstract: Fifty-five patients placed on tipranavir/ritonavir 500/200 mg twice a day (27 with enfuvirtide and 28 without) underwent tipranavir and ritonavir plasma concentration measurements by high-pressure liquid chromatography. Markedly higher tipranavir and ritonavir trough concentrations were observed in enfuvirtide recipients. The modelling of sparse plasma samples using a first order absorption and elimination monocompartmental model without time lag predicted higher tipranavir elimination half-life and volume of distribution in enfuvirtide takers. This unexpected drug-drug interaction warrants further investigation.
authors.affiliation: Department of Infectious Diseases, University of Turin, Turin, Italy.
authors.forename: Daniel
authors.initials: D
authors.lastname: González de Requena
authors.forename: Andrea
authors.initials: A
authors.lastname: Calcagno
authors.forename: Stefano
authors.initials: S
authors.lastname: Bonora
authors.forename: Laura
authors.initials: L
authors.lastname: Ladetto
authors.forename: Antonio
authors.initials: A
authors.lastname: D'Avolio
authors.forename: Mauro
authors.initials: M
authors.lastname: Sciandra
authors.forename: Marco
authors.initials: M
authors.lastname: Siccardi
authors.forename: Olivia
authors.initials: O
authors.lastname: Bargiacchi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Sinicco
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Perri
mesh_terms: D019380:Anti-HIV Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D015331:Cohort Studies; D004347:Drug Interactions; D000077560:Enfuvirtide; D005260:Female; D015700:HIV Envelope Protein gp41 / Q000627:therapeutic use; D023581:HIV Fusion Inhibitors / Q000493:pharmacokinetics / Q000627:therapeutic use; D015658:HIV Infections / Q000188:drug therapy; D017320:HIV Protease Inhibitors / Q000493:pharmacokinetics / Q000627:therapeutic use; D015497:HIV-1; D006207:Half-Life; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000493:pharmacokinetics* / Q000627:therapeutic use; D011725:Pyridines / Q000493:pharmacokinetics* / Q000627:therapeutic use; D011753:Pyrones / Q000493:pharmacokinetics* / Q000627:therapeutic use; D019438:Ritonavir / Q000493:pharmacokinetics* / Q000627:therapeutic use; D013449:Sulfonamides
chemical_list: D019380:Anti-HIV Agents; 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