Pharmacokinetic Modeling of Methadone

Study Overview
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Brief Summary
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The management of patients with opioid addiction is a challenge insofar as many distractors or variability factors can interfere with the control of the addiction, whether they are psychological, psychiatric, environmental, pharmacokinetic or pharmacodynamic. Understanding this variability is potentially to be able to adjust a priori a dosage and to identify the factors of clinical response. Few population pharmacokinetic models exist for methadone and they generally concern the management of pain in palliative care patients or the management of opioid withdrawal syndrome in neonates. The hypothesis is therefore that the creation of such a model would make it possible to reduce patients' withdrawal periods, to set a target for plasma concentrations with a view to reducing dosages, and to empower the patient in his choice to monitor blood concentrations facilitated by a minimally invasive sampling device.

Official Title
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Pharmacokinetic Population Modeling of Methadone in Patients Managed for Opioid Opioid Addiction

Conditions
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Toxicomania

Intervention / Treatment
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* Biological: Blood sampling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Major patients on methadone for at least one month. Hospitalization for withdrawal in the addictology department of La Colombière or consultation within the unit for the treatment of drug addiction and dependence (Addictology Department). Exclusion Criteria: Patients that cannot be sampled because of weakened veins Legally protected Unable to received information about the study Exclusion period determined by previous study Adult protected by law or patient under guardianship Not affiliated to french social security system Not able to give written inform consent Pregnant or breastfeeding woman Underaged patients (under 18 years old) Patient under court protection

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 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: Health Services Research
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Therapeutic drug monitoring of methadone<br>6 samplings per subject: 3 venipunctures and 3 microsamplings | Biological: Blood sampling<br>* Patient will be subjected to 3 blood sampling over 24hours. At H0, H4 and H12-24. For each one, one microsampling and one venipuncture<br>* Other names: Volumetric absorptive microsampling;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak concentration (Cmax) | To evaluate and estimate methadone/EDDP (metabolite) Cmax for patients treated for opioid addiction. | 18 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| C12h-24h concentration | To evaluate and estimate methadone/EDDP (metabolite) concentration between 12 and 24h post-administration for patients treated for opioid addiction. | 18 months | 
| Residual concentration (C0) | To evaluate and estimate residual methadone/EDDP (metabolite) concentration for patients treated for opioid addiction. | 18 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pharmacokinetics, methadone, microsampling, modeling