Published in:
01-04-2011 | Original Article
Lack of effect of casopitant on the pharmacokinetics of docetaxel in patients with cancer
Authors:
Uday B. Dandamudi, Laurel M. Adams, Brendan Johnson, John Bauman, Shannon Morris, Sharon Murray, R. Timothy Webb, Elaina Gartner, Raymond Hohl, Lionel D. Lewis
Published in:
Cancer Chemotherapy and Pharmacology
|
Issue 4/2011
Login to get access
Abstract
Purpose
The neurokinin-1 receptor antagonist, casopitant, is a weak-to-moderate inhibitor of cytochrome P450 isoenzyme 3A4 (CYP3A) and has the potential to inhibit the metabolism of CYP3A substrates such as docetaxel.
Methods
Fourteen cancer patients were enrolled in this phase 1, open-label, randomized, two-period crossover study. Intravenous (i.v.) docetaxel was coadministered with oral ondansetron and dexamethasone with (Regimen B) or without (Regimen A) 150 mg single-dose oral casopitant.
Results
The geometric least-squares mean Regimen B: Regimen A ratios (90% confidence interval) for docetaxel maximum plasma concentration and area under the concentration–time curve from time 0 extrapolated to infinity were 0.97 (0.83, 1.12) and 1.06 (0.94, 1.19), respectively. Coadministration of casopitant and docetaxel was well tolerated, with adverse event profiles and absolute neutrophil count nadirs similar for both treatments.
Conclusions
Cmax and AUC of docetaxel were similar when given as monotherapy or when given in combination with casopitant. Likewise, absolute neutrophil count nadirs were similar for docetaxel alone or docetaxel with casopitant.