Pharmacokinetics and target attainment of mycophenolate in pediatric renal transplant patients

Area of Science:

• Pharmacology
• Transplantation Medicine
• Pediatric Nephrology

Background:

• Mycophenolic acid (MPA) is a crucial immunosuppressant for preventing rejection in pediatric renal transplant recipients.
• Significant inter- and intraindividual variability in MPA exposure necessitates therapeutic drug monitoring (TDM) for personalized dosing.
• Understanding factors influencing MPA exposure is vital for optimizing treatment outcomes in children.

Purpose of the Study:

• To investigate MPA exposure, measured as area under the curve (AUC), in pediatric renal transplant patients.
• To identify key factors affecting MPA exposure and assess the attainment of therapeutic targets.
• To evaluate the potential of intensified TDM for improving treatment efficacy.

Main Methods:

• Retrospective analysis of pediatric renal transplant patients transplanted between 1998 and 2014.
• Categorization into two groups based on time post-transplantation: early (Group 1) and late (Group 2).
• Measurement of MPA AUC0-12h and assessment of target attainment (30-60 mg h/L).

Main Results:

• MPA AUC0-12h was 29.7 mg h/L in Group 1 and 56.6 mg h/L in Group 2, despite lower doses in Group 2.
• Only 46% of patients in Group 1 achieved the target AUC0-12h.
• Time since transplantation and serum creatinine levels significantly correlated with MPA exposure, explaining 36% of variability.

Conclusions:

• MPA exposure is highly variable in pediatric renal transplant recipients, particularly in the early post-transplant period.
• Current TDM strategies may be insufficient for achieving therapeutic targets in a significant proportion of children.
• Implementing more intensive and earlier TDM could enhance MPA dose individualization and improve target attainment, potentially leading to better graft outcomes.