title: The effect of different doses of cyclosporin A on the systemic exposure of orally administered paclitaxel.
abstract: The objective of this study was to define the minimally effective dose of cyclosporin A (CsA) that would result in a maximal increase of the systemic exposure to oral paclitaxel. Six evaluable patients participated in this randomized cross-over study in which they received at two occasions two doses of 90 mg/m(2) oral paclitaxel 7 h apart in combination with 10 or 5 mg/kg CsA. Dose reduction of CsA from 10 to 5 mg/kg resulted in a statistically significant decrease in the area under the plasma concentration-time curve (AUC) and time above the threshold concentrations of 0.1 microM (T>0.1 microM) of oral paclitaxel. The mean (+/-SD) AUC and T>0.1 microM values of oral paclitaxel with CsA 10 mg/kg were 4.29+/-0.88 microM x h and 12.0+/-2.1 h, respectively. With CsA 5 mg/kg these values were 2.75+/-0.63 microM x h and 7.0+/-2.1 h, respectively (p=0.028 for both parameters). In conclusion, dose reduction of CsA from 10 to 5 mg/kg resulted in a significant decrease in the AUC and T>0.1 microM values of oral paclitaxel. Because CsA 10 mg/kg resulted in similar paclitaxel AUC and T>0.1 microM values compared to CsA 15 mg/kg (data which we have published previously), the minimally effective dose of CsA is determined at 10 mg/kg.
authors.affiliation: Department of Medical Oncology, Netherlands Cancer Institute/Slotervaart Hospital, Louwesweg 6, 1066 EC Amsterdam, The Netherlands. apmmg@slz.nl
authors.forename: M M
authors.initials: MM
authors.lastname: Malingré
authors.forename: J H
authors.initials: JH
authors.lastname: Beijnen
authors.forename: H
authors.initials: H
authors.lastname: Rosing
authors.forename: F J
authors.initials: FJ
authors.lastname: Koopman
authors.forename: O
authors.initials: O
authors.lastname: van Tellingen
authors.forename: K
authors.initials: K
authors.lastname: Duchin
authors.forename: W W
authors.initials: WW
authors.lastname: ten Bokkel Huinink
authors.forename: M
authors.initials: M
authors.lastname: Swart
authors.forename: J
authors.initials: J
authors.lastname: Lieverst
authors.forename: J H
authors.initials: JH
authors.lastname: Schellens
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000493:pharmacokinetics* / Q000633:toxicity; D019540:Area Under Curve; D001943:Breast Neoplasms / Q000188:drug therapy; D018288:Carcinoma, Small Cell / Q000188:drug therapy; D016572:Cyclosporine / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005767:Gastrointestinal Diseases / Q000139:chemically induced; D006402:Hematologic Diseases / Q000139:chemically induced; D006801:Humans; D007262:Infusions, Intravenous; D008175:Lung Neoplasms / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D017239:Paclitaxel / Q000008:administration & dosage*; D011292:Premedication; D013274:Stomach Neoplasms / Q000188:drug therapy; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy; D014594:Uterine Neoplasms / Q000188:drug therapy
chemical_list: D016572:Cyclosporine; D017239:Paclitaxel