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Updated: Jun 23, 2026
08:38
Quantification of the Immunosuppressant Tacrolimus on Dried Blood Spots Using LC-MS/MS
Published on: November 8, 2015
CYP3A polymorphisms and immunosuppressive drugs in solid-organ transplantation
1Office of Clinical Pharmacology, Center for Drug Research and Evaluation, The US FDA, Silver Spring, MD 20993, USA. jian.wang@fda.hhs.gov
Expert Review of Molecular Diagnostics
|May 14, 2009
Summary
Genetic variations in CYP3A enzymes significantly impact how the body processes immunosuppressive drugs like tacrolimus. Understanding these genetic factors, or polymorphisms, can help personalize drug therapy for better patient outcomes.
Area of Science:
- Pharmacogenomics
- Drug Metabolism
- Immunosuppression
Background:
- Immunosuppressive drugs exhibit narrow therapeutic indices and significant interpatient variability.
- Genetic factors, specifically single-nucleotide polymorphisms (SNPs) in drug-metabolizing enzymes, offer potential for personalized therapy.
Purpose of the Study:
- To review the impact of CYP3A polymorphisms on the pharmacokinetics of immunosuppressive medications.
- To assess the current understanding of CYP3A genetic variations in relation to drug efficacy and safety.
Main Methods:
- Literature review of retrospective studies on CYP3A polymorphisms and immunosuppressive drug pharmacokinetics.
- Analysis of existing data on the relationship between CYP3A5*1/*3, CYP3A4*/*1B polymorphisms and drug exposure.
Main Results:
- A strong association exists between CYP3A5*1/*3 polymorphism and tacrolimus pharmacokinetics.
- The influence of CYP3A5*1/*3 or CYP3A4*/*1B on ciclosporin and sirolimus pharmacokinetics remains uncertain.
- CYP3A polymorphisms may partly explain variability in drug interactions.
Conclusions:
- CYP3A genetic polymorphisms play a role in immunosuppressive drug variability, particularly for tacrolimus.
- Further prospective, randomized studies are required to fully elucidate the impact of CYP3A genetics on immunosuppressive drug response.
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