Study of Tacrolimus Used for Pediatric Patients With Nephrotic Syndrome Based on Pharmacogenomics and Metabonomics

Study Overview
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Brief Summary
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Tacrolimus is recommended to be the first line therapeutic medication within the several immunosuppressive agents when treating refractory pediatric nephrotic syndrome, because of its definite efficacy and low toxicity. But there are still some key problems which hinder the using of tacrolimus in clinic, such as its narrow therapeutic widow, great individual difference of pharmacokinetics. Routine therapeutic drug monitoring(TDM) is needed in practice. But the disadvantage of TDM is hysteresis, which could lead to treatment failure or toxicity. To find out the reasons of great pharmacokinetic difference between patients and find out the individual proper dosage before administration are important for the clinical using of tacrolimus. It is hot in research of tacrolimus in organ transplant field, such as the association between gene polymorphisms of cytochrome P-450 3A4, 3A5 and multiple drug resistant gene(MDR1) and concentration of tacrolimus. However, there is few study about pharmacogenomics and metabonomics of tacrolimus in patients of nephrotic syndrome. The aim is to study the relationships between pharmacogenomics, metabonomics of tacrolimus and its efficacy, toxicity and blood concentration in patients of nephrotic syndrome, to find out the exact dosage before administration, to provide reference to individual drug administration.

Detailed Description
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Investigators will collect data about efficacy and adverse drug reaction(ADR) such as time of efficacy when evaluated, how to evaluate ADR, data of demography, etc.

Official Title
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Guangzhou Women and Children's Medical Center

Conditions
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Nephrotic Syndrome

Intervention / Treatment
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* Other: therapeutic drug monitoring


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with refractory nephrotic syndrome; patients age ≤14y. Exclusion Criteria: patients are sensitive to steroid; combined therapy with other immunosuppressive agent; combined using drugs which maybe interact the concentration of tacrolimus; with other malignant disease, such as tumor.

Ages Eligible for Study
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Minimum Age: 1 Month
Maximum Age: 14 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| good efficacy<br>using therapeutic drug monitoring to adjust the dose of tacrolimus. patients can reach effective outcome. | Other: therapeutic drug monitoring<br>* with therapeutic drug monitoring , dose of tacrolimus can be adjusted by therapeutic drug monitoring.<br>|
| poor efficacy<br>using therapeutic drug monitoring to adjust the dose of tacrolimus. patients can not reach effective outcome. | Other: therapeutic drug monitoring<br>* with therapeutic drug monitoring , dose of tacrolimus can be adjusted by therapeutic drug monitoring.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Genotypes as measured by polymerase chain reaction-restriction fragment length polymorphism | genotype are collected from hospital system. | 1 week | 
| Concentration as measured by liquid chromatography mass spectrometry | concentration of tacrolimus are collected from hospital system. | 1 week | 
| Relationship between genotypes and concentration as analyzed at 1 week | using Statistic Package for Social Science 21.0 software to analyze the relationship between gene polymorphism and concentration. | 1 week |