Nor)Clozapine Kinetics and Side Effects in Therapy Resistant Schizophrenia and the Optimal Sampli… (NCT06749041) | Clinical Trial Compass
Not Yet RecruitingNot Applicable
Nor)Clozapine Kinetics and Side Effects in Therapy Resistant Schizophrenia and the Optimal Sampling Time for Therapeutic Drug Monitoring
60 participantsStarted 2024-12-23
Plain-language summary
The goal of this observational study is to better understand how clozapine treatment can be tailored as regards minimizing side effects and optimizing efficacy and monitoring. Firstly, how clozapine is broken down into norclozapine in the liver and how both clozapine and norclozapine affect side effects are examined. In order to investigate this metabolization process in the liver inflammation levels in the blood are assessed, which inhibit the conversion of clozapine into norclozapine. In addition, various factors related to physical health are assessed, such as blood sugar, cholesterol, weight, waist circumference, blood pressure and heart rate. The role of hormones is investigated, such as cortisol, a stress hormone that affects metabolism and stress levels. Amino acids are examined, which are building blocks of proteins, and specific parts of DNA that influence clozapine metabolism. In addition, investigation follows whether 12 hours after ingestion is a well-chosen time at which the amount of clozapine is measured in the blood in case of ingestion once a day and twice a day. Finally, specific side effects of clozapine are assessed - with special attention to stool - and the severity of the psychiatric symptoms in patients with therapy resistant schizophrenia spectrum disorders.
Who can participate
Age range
18 Years – 70 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Standard treatment of a stable, oral dose of clozapine for at least one week (at steady state).
* Age between 18-70 years.
* Registered time of intake as well as sampling time and dosage.
* Registered smoking status (yes/no).
* At least two samples in the elimination phase of clozapine with both clozapine and norclozapine measured.
* Measurement of the white cell count at least every three months or more often.
* Routine metabolic screening performed at moment of inclusion.
* Subjects should be able to understand the study information and procedures and give informed consent or when incapacitated subjects are not reliably able to give informed consent their legal representatives should give informed consent under the condition that these subjects are willing to participate.
Exclusion Criteria:
* Pregnancy.
* Malignancy or treatment with immunosuppressive medication.
* Samples where cessation, start or dose change of interacting co-medication (such as valproic acid, gemfibrozil, fluvoxamine, omeprazole and cyclic oral contraceptives \[21 on, 7 days off\]) or changes in use of tobacco containing products occurred within seven days prior to blood sampling (21, 28, 34, 35).
* Acute inflammation, infection or samples shortly after intoxication. In case this information is unknown, it may be derived by large unexpected change in levels compared to previous or target levels.
* Not sampled at Starlet (blood collection site) or sampled by dried blood spot
* Un…
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Correlation between serum level HbA1c and (nor)clozapine concentrations and ratio.
Timeframe: For each patient two years of follow-up will be collected (until a maximum of 01-12-2027).