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Dosage Recommendations for Off-label Use of Mycophenolate Mofetil in Pediatric Patients with Thalassemia Undergoing Hematopoietic Stem Cell Transplantation: An Approach Based on Population Pharmacokinetic Studies

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Date 2025 Feb 1
PMID 39891881
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Abstract

Background And Objectives: As an immunosuppressant, mycophenolate mofetil (MMF) is used to prevent graft versus host disease (GVHD) in patients after hematopoietic stem cell transplantation (HCT). This study aimed to establish a population pharmacokinetic model and simulate the dosage protocol in HCT patients with thalassemia (TM) to fill the gap of lacking MMF dosing regimen.

Methods: The mycophenolic acid (MPA) plasma concentrations were obtained from HCT patients with TM after using MMF. The population pharmacokinetic (PPK) parameters were obtained by NONMEM (Version VII, Level 2.0; ICON Development Solutions, Ellicott City, MD, USA) program. Monte Carlo simulations were used to determine the optimal dosing.

Results: A total of 239 blood samples from 31 pediatric patients were available, the PPK of MPA was described as a two-compartment model. The typical values for MPA clearance (CL), central distribution volume (V), peripheral distribution volume (V), intercompartmental clearance (Q), and absorption rate constant (Ka) were 14.9 L/h, 83.5L, 141L, 3.13 L/h, and 1.37/h respectively. The inter-individual variability (IIV) of CL and V were 35% and 41%, respectively. Simulation results suggested that, as the patient's body surface area (BSA) value increased, MMF dosage initiated from 500 mg twice daily was effective.

Conclusions: A 'tiered' dosage regimen including patient urea and with doses stratified across BSA quartiles, rather than a 'one dose fits all' regimen, would help individualize MMF therapy in this population.

References
1.
Adly A, Ebeid F . Cultural preferences and limited public resources influence the spectrum of thalassemia in Egypt. J Pediatr Hematol Oncol. 2015; 37(4):281-4. DOI: 10.1097/MPH.0000000000000327. View

2.
Au W, Li C, Fang J, Chen G, Sun X, Li C . Assessment of iron overload in very young children with limited thalassemia care resources in South China. Hemoglobin. 2014; 38(2):119-26. DOI: 10.3109/03630269.2014.880715. View

3.
Lee T, von Riedemann S, Tricta F . Cost-utility of chelators in transfusion-dependent β-thalassemia major patients: a review of the pharmacoeconomic literature. Expert Rev Pharmacoecon Outcomes Res. 2014; 14(5):651-60. DOI: 10.1586/14737167.2014.927314. View

4.
Weidlich D, Kefalas P, Guest J . Healthcare costs and outcomes of managing β-thalassemia major over 50 years in the United Kingdom. Transfusion. 2016; 56(5):1038-45. DOI: 10.1111/trf.13513. View

5.
Oellerich M, Shipkova M, Schutz E, Wieland E, Weber L, Tonshoff B . Pharmacokinetic and metabolic investigations of mycophenolic acid in pediatric patients after renal transplantation: implications for therapeutic drug monitoring. German Study Group on Mycophenolate Mofetil Therapy in Pediatric Renal Transplant.... Ther Drug Monit. 2000; 22(1):20-6. DOI: 10.1097/00007691-200002000-00004. View