Feasibility and Preliminary Outcomes of Area Under the Concentration‐Time Curve ( AUC )‐Guided Tacrolimus and Mycophenolate Dosing in Pediatric Kidney Transplant Recipients

ABSTRACT Background This pilot study evaluated the feasibility of integrating an immunosuppressant area under the concentration‐time curve (AUC) monitoring for tacrolimus and mycophenolic acid (MPA) into pediatric kidney transplantation care. Methods Dedicated test codes, an AUC requisition form, and a coordinated laboratory sampling process were established for tacrolimus and MPA AUC. AUC was calculated using the ISBA 3.0 Bayesian pharmacokinetic platform. AUC results were correlated with doses, trough concentrations (C 0 ), 3 h post‐dose concentrations (C 3h ), and clinical outcomes. Results The AUC protocol was successfully integrated into the routine clinical workflow. Tacrolimus AUC showed correlations with dose ( r = 0.85) and C 0 ( r = 0.82); similarly, MPA AUC showed correlation with dose ( r = 0.61) and C 3h ( r = 0.65). Of the 21 Tacrolimus AUC measurements, 76% were within the target range, and 24% were below the range. For MPA AUC measurements, 65% (13/20) were within the target range, 5% (1/20) were below the range, and 30% (6/20) were above the range. Following individual AUC measurements, the tacrolimus dose was adjusted after 43% (9/21) of measurements, and the mycophenolate mofetil (MMF) dose was adjusted after 50% (10/20) of measurements. Conclusion This AUC pilot study demonstrated the feasibility of integrating AUC‐guided monitoring into the routine management of pediatric kidney transplant recipients.