Pharmacokinetics Study of Mycophenolic Acid in Patients With an Autoimmune Bullous Dermatose, Pemphigus or Cicatricial Pemphigoid.

Study Overview
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Brief Summary
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The main autoimmune bullous dermatoses are pemphigus and cicatricial pemphigoid. Pemphigus is an autoimmune dermatological disease characterized by the production of anti-desmoclesin antibodies 1 and 3, affecting the skin and mucous membranes.The cicatricial pemphigoid is an autoimmune dermatological disease, characterized by the production of anti-zone antibodies of the basal membrane and characterized by a predominant mucosal involvement. Mycophenolic acid (MPA) is an increasingly used form of corticosteroid. Despite its increasing use, pharmacokinetics in autoimmune bullous dermatosis remain little studied.

Official Title
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Pharmacokinetics Study of Mycophenolic Acid in Patients With an Autoimmune Bullous Dermatose, Pemphigus or Cicatricial Pemphigoid.

Conditions
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Autoimmune Bullous Dermatose

Intervention / Treatment
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* Drug: Cellcept® in autoimmune bullous dermatoses


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > or = 18 years. Patient treated by Mycophénolate Mofétil (MMF) per os (Cellcept®) for an autoimmune bullous dermatose (pemphigus or cicatricial pemphigoid) for at least 30 days according to the recommendations (PNDS Pemphigus and cicatricial pemphigoid HAS 2011) Patient able to understand the nature, purpose and methodology of the study Patient affiliated to the French social security system or equivalent Patient who have signed an informed consent form Exclusion Criteria: Pregnant or breast-feeding women or women of childbearing potential without efficient contraception (based on a declaration) Patient under legal protection. Patient deprived of freedom Patient with any altered mental status or any psychiatric condition that would interfere with the understanding of the study.

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 60 patients will be used to build and validate the system<br>The first 30 patients will be used to build and validate the pharmacokinetic modeling of MPA in pemphigus.The 30 patients included later will provide additional data. | Drug: Cellcept® in autoimmune bullous dermatoses<br>* The administration will follow the recommendations for the use of Cellcept® in autoimmune bullous dermatoses<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of the Bayesian estimator performance | The evaluation of the Bayesian estimator performance will be based on its capacity to predict MPA AUC (Area Under the Curve), expressed as the bias (%) and the precision (root mean square error; RMSE) between the predicted AUC calculated using a limited number of samples performed in the first 4 hours post dosing and the observed AUC estimated using the reference method (trapezoidal rule method). A Bland Altman curve will be constructed. | 8 hours |