The aim of this study was to characterize the pharmacokinetics of mycophenolic acid (MPA) and MPA glucuronide (MPAG) in Chinese renal transplant patients taking enteric-coated mycophenolate sodium (EC-MPS). Limited sampling strategies (LSSs) were developed to estimate the area under the concentration curve from 0 to 12 hours (AUC0–12h) of total and free MPA. Another objective was to investigate the correlation between high-performance liquid chromatography (HPLC) and enzyme-multiplied immunoassay technology (EMIT) for total MPA determination.Methods:
Serial blood samples were collected over 12 hours from 15 patients who were administered multiple doses of EC-MPS. LSS was developed by multiple stepwise regression analysis. Measurement by HPLC and EMIT was compared using Passing–Bablok regression and Bland–Altman analysis.Results:
Normalized to 720 mg twice daily, the AUC0–12h of total MPA and MPAG was 43.0 ± 17.4 and 653 ± 329 mg·h/L, respectively, whereas the free MPA AUC0–12h was 1.368 ± 0.988 mg·h/L. The free fraction of MPA was 3.01% ± 3.15%. The combination of C2h–C4h–C6h and C2h–C4h–C6h–C8h was found to be superior to estimate total and free MPA simultaneously. The EMIT showed an acceptable correlation with HPLC, with an AUC0–12h overestimation of 11.32% ± 15.77%.Conclusions:
The pharmacokinetic profile of total and free MPA and its main metabolite MPAG was examined in Chinese adult renal transplant patients receiving EC-MPS. The use of LSS to estimate individual free and total MPA exposure could be useful in optimizing patient care.