Development of a Complex Parent-Metabolite Joint Population Pharmacokinetic Model
Journal Title: The AAPS Journal - Year 2011, Vol 13, Issue 3
Abstract
This study aimed to develop a joint population pharmacokinetic model for an antipsychotic agent in development ({"type":"entrez-protein","attrs":{"text":"S33138","term_id":"423514","term_text":"pir||S33138"}} S33138) and its active metabolite ({"type":"entrez-protein","attrs":{"text":"S35424","term_id":"422490","term_text":"pir||S35424"}} S35424) produced by reversible metabolism. Because such a model leads to identifiability problems and numerical difficulties, the model building was performed using the FOCE-I and the Stochastic Approximation Expectation Maximization (SAEM) estimation algorithms in NONMEM and MONOLIX, respectively. Four different structural models were compared based on Bayesian information criteria. Models were first written as ordinary differential equations systems and then in closed form (CF) to facilitate further analyses. The impact of polymorphisms on genes coding for the CYP2C19 and CYP2D6 enzymes, respectively involved in the parent drug and the metabolite elimination were investigated using permutation Wald test. The parent drug and metabolite plasma concentrations of 101 patients were analyzed on two occasions after 4 and 8 weeks of treatment at 1, 3, 6, and 24 h following daily oral administration. All configurations led to a two compartment model with back-transformation of the metabolite into the parent drug and a first-pass effect. The elimination clearance of the metabolite through other processes than back-transformation was decreased by 35% [9–53%] in CYP2D6 poor metabolizer. Permutation tests were performed to ensure the robustness of the analysis, using SAEM and CF. In conclusion, we developed a complex joint pharmacokinetic model adequately predicting the impact of CYP2D6 polymorphisms on the parent drug and its metabolite concentrations through the back-transformation mechanism.
Authors and Affiliations
Julie Bertrand, Céline M. Laffont, France Mentré, Marylore Chenel, Emmanuelle Comets
Best practices during bioanalytical method validation for the characterization of assay reagents and the evaluation of analyte stability in assay standards, quality controls, and study samples
Characterization of the stability of analytes in biological samples collected during clinical studies together with that of critical assay reagents, including analyte stock solutions, is recognized as an important compon...
Renal Organic Anion Transporters (SLC22 Family): Expression, Regulation, Roles in Toxicity, and Impact on Injury and Disease
Organic solute flux across the basolateral and apical membranes of renal proximal tubule cells is a key process for maintaining systemic homeostasis. It represents an important route for the elimination of metabolic wast...
Challenges and Opportunities in Achieving Bioequivalence for Fixed-Dose Combination Products
Fixed-dose combination (FDC) products are becoming a popular treatment option because of increased patient compliance and convenience, improved clinical effectiveness, and reduced cost to the patient, among several other...
Effects of Surface Composition on the Aerosolisation and Dissolution of Inhaled Antibiotic Combination Powders Consisting of Colistin and Rifampicin
The online version of this article (doi:10.1208/s12248-015-9848-z) contains supplementary material, which is available to authorized users.
Establishing the Quantitative Relationship Between Lanreotide Autogel®, Chromogranin A, and Progression-Free Survival in Patients with Nonfunctioning Gastroenteropancreatic Neuroendocrine Tumors
The online version of this article (doi:10.1208/s12248-016-9884-3) contains supplementary material, which is available to authorized users.