Current and former clozapine users (English)

This study (CLOZIN) looks at clozapine treatment in psychotic disorders. These include schizophrenia, schizophreniform disorder, schizoaffective disorder and psychotic disorders not otherwise specified (NOS). The hearing of voices, for example, is common in these disorders. For treating this disorder, clozapine is prescribed when other antipsychotic medication did not have sufficient effect. As this is quite late in the disease, we want to create a tool to predict respone and side effects. The study is conducted by means of a short visit during which we take a blood sample and conduct a questionnaire. With the use of blood sampling, the DNA can be investigated.

What kind of patients are we looking for?
To create the prediction tool, 4000 patients with mental disorders are required. We are looking for people who:
1) Are diagnosed with schizophrenia, schizoaffective, or schizophreniform disorder.
2) Use clozapine or have used Clozapine.
3) Speak and read the language of the country of the participating center.
4) Are able of making their own decision whether they want to participate in this research.
5) Are at least 18 years of age.

Patients cannot participate if:
1) They are institutionalized in a psychiatric facility under custody.
2) They have Parkinson’s disease.

What exactly is done during the visit?
Clozapine users often get their blood checked to monitor side effects. If you participate in CLOZIN, we will take an additional tube of blood (10 milliliters) during one of these blooddraws. In most cases, there will not be an additional venipuncture. If this is necessary, this will be discussed first. In  addition, a doctor or researcher will conduct a conversation of approximately 10 minutes. In this conversation the participant will be asked about substance use, side effects and how well clozapine works.. The study saves the data under a code, not under the participant’s name. We work in line with prinacy laws and Good Clinical Practice.

Is participation voluntary?
Participation is completely voluntary. If someone decides not to participate, it is not necessary to explain why not. The decision does not affect the received care. If someone decides to participate, it is always possible to consider to withdraw permission at any time without having to tell why.

What do you get in return?
For participation in the research, the participant will receive € 5,- compensation (if allowed by local legislation). In addition, the participant contributes to the improvement of the treatment of psychoses.

What are the possible risks?
There is no risk of participation in this research. For example, there is usually no extra blood draw.

Who organizes the research?
CLOZIN was founded by a psychiatrist and neuroscientist Jurjen Luykx, working at the Brain Center Rudolf Magnus that is part of the University Medical Center Utrecht (UMCU). The study is coordinated by Marte van der Horst, MSc, working at the UMCU Psychiatry Department. The sponsor was Prof. dr. René Kahn, UMCU, and the study is now made possible by GGNet.

Which centers participate in the research?
The CLOZIN research does not only take place in UMC Utrecht. There are several institutions that also contribute(d) to research. A recent overview can be found in the group.