Drug target molecules to guide immunosuppression.

Area of Science:

• Pharmacology
• Transplantation Medicine
• Immunology

Background:

• Organ transplant recipients require lifelong immunosuppression, facing significant individual variability in drug response.
• Traditional therapeutic drug monitoring (TDM) focuses on drug concentrations (pharmacokinetics) but doesn't fully account for response variability.
• Understanding and addressing interindividual differences in drug response is essential for optimizing immunosuppressive therapy.

Purpose of the Study:

• To explore pharmacodynamic monitoring as a method to personalize immunosuppressant therapy.
• To identify and evaluate potential pharmacodynamic markers for monitoring immunosuppressant drug effects.
• To assess the clinical utility and potential implementation of pharmacodynamic monitoring strategies.

Main Methods:

• Review of experimental and clinical data on pharmacodynamic markers for immunosuppressants.
• Evaluation of specific markers for mycophenolic acid (MPA) and mTOR inhibitors (e.g., IMPDH activity, p70S6K phosphorylation).
• Analysis of nuclear factor of activated T-cells (NFAT) response element assays for calcineurin inhibitor (CNI) monitoring.

Main Results:

• Antithymocyte globulin monitoring via lymphocyte subset counts is an established pharmacodynamic method.
• Potential markers like IMPDH activity and p70S6K phosphorylation exist for MPA and mTOR inhibitors, respectively.
• NFAT RGE assays show promise for CNI pharmacodynamic monitoring, with existing documentation and potential for clinical integration.

Conclusions:

• Pharmacodynamic monitoring offers a way to individualize immunosuppression, addressing response variability.
• While some markers are promising (e.g., NFAT RGE for CNIs), further research and standardization are needed.
• Pharmacodynamic monitoring, particularly NFAT RGE assays for CNIs, is nearing clinical applicability.