Abstract | PURPOSE: The aim of this study was to explore the effect of several demographic, biological, and pharmacogenetic covariates on the disposition of imatinib and its main metabolite ( CGP74588) in both adults and children. EXPERIMENTAL DESIGN: Thirty-three children with solid malignancies included in a phase II exploratory study and 34 adults with gastrointestinal stromal tumors received 340 mg/m(2) and 400 mg imatinib, respectively. Plasma imatinib and CGP74588 concentrations observed on day 1 and at steady-state were analyzed by a population pharmacokinetic method (NONMEM) to evaluate the effect of age, body weight, age, sex, albuminemia, plasma alpha1-acid glycoprotein (AGP), and eight polymorphisms corresponding to ABCB1, ABCG2, CYP3A4, CYP3A5, and AGP (pharmacogenetic data available for 46 of 67 patients). RESULTS: Analysis of the whole data set in 67 patients showed that apparent clearance (CL/F) of imatinib was positively correlated with body weight and albuminemia and negatively with AGP. By considering these three covariates, the interindividual variability on CL/F decreased from 47% to 19%. The apparent clearance of CGP74588 was similarly dependent on both body weight and AGP and significantly lower (30% reduction) at steady-state. By adding genotype status to the final covariate imatinib model, a 22% reduction in CL/F was observed in heterozygous compared with wild-type patients corresponding to ABCG2 c.421C>A (P<0.05). CONCLUSIONS: By considering morphologic and biological covariates, a unique covariate model could be used to accurately describe imatinib pharmacokinetics in patients ages 2 to 84 years. Morphologic and biological characteristics have a stronger influence than pharmacogenetics on imatinib pharmacokinetics.
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Authors | Aurélie Petain, Darouna Kattygnarath, Julie Azard, Etienne Chatelut, Catherine Delbaldo, Birgit Geoerger, Michel Barrois, Sophie Séronie-Vivien, Axel LeCesne, Gilles Vassal, Innovative Therapies with Children with Cancer European consortium |
Journal | Clinical cancer research : an official journal of the American Association for Cancer Research
(Clin Cancer Res)
Vol. 14
Issue 21
Pg. 7102-9
(Nov 01 2008)
ISSN: 1078-0432 [Print] United States |
PMID | 18981009
(Publication Type: Journal Article)
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Chemical References |
- Benzamides
- Blood Proteins
- CGP 74588
- Glycoproteins
- Piperazines
- Pyrimidines
- Serum Albumin
- Imatinib Mesylate
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Topics |
- Adolescent
- Adult
- Age Factors
- Aged
- Aged, 80 and over
- Benzamides
- Blood Proteins
(metabolism)
- Body Weight
- Child
- Child, Preschool
- Gastrointestinal Stromal Tumors
(genetics, metabolism)
- Glycoproteins
(blood)
- Humans
- Imatinib Mesylate
- Metabolic Clearance Rate
(genetics)
- Middle Aged
- Pharmacogenetics
- Piperazines
(metabolism, pharmacokinetics, pharmacology)
- Polymorphism, Genetic
- Population Groups
- Pyrimidines
(metabolism, pharmacokinetics, pharmacology)
- Serum Albumin
- Sex Factors
- Young Adult
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