Primary research questions: 1. Is there a difference in effectiveness of clozapine treatment compared to olanzapine treatment in the reduction of substance use disorders of patients with schizophrenia and related psychotic disorders? 2. What is the…
ID
Source
Brief title
Condition
- Other condition
- Schizophrenia and other psychotic disorders
- Lifestyle issues
Synonym
Health condition
verslaving
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
1. At baseline, week 4, week 8, month 6 or at moment of withdrawal from the
study: Self reported substance use - CIDI section B,J,L and Recent Drug Use
Urinalysis
2. Cost-effectiveness - lncremental cost-effectiveness ratio (ICER): difference
in costs/the difference in effectiveness (clozapine-olanzapine).
Secondary outcome
1. Direct and indirect medical costs, and non-medical costs
2. Other clinical outcome: - Psychopathology: PANSS, YBOCS, OCDUS, QoL, SWN,
CGI, GAF, LCS,
- Adverse effects: - leucopoenia, agranulocytosis, - Time to non- compliance, -
Time to withdrawal from study, - Quality of life, Quality adjusted life years
(QALYs)
Background summary
The lifetime prevalence of substance use disorders (SUD) of patients with
schizophrenia is about 50%. Substances commonly abused by patients with
schizophrenia include nicotine, alcohol, cannabis, cocaine and amphetamines.
Co-morbid substance abuse is associated with poor outcome. There are some
indications that clozapine has a favourable effect on SUD in schizophrenia.
These possible benefits should be weighed against the risk of adverse effects.
If this study proves that clozapine is effective in reducing SUD of patients
with schizophrenia, clozapine should get a more prominent place in the
treatment protocol of patients with SUD and schizophrenia.
Study objective
Primary research questions: 1. Is there a difference in effectiveness of
clozapine treatment compared to olanzapine treatment in the reduction of
substance use disorders of patients with schizophrenia and related psychotic
disorders? 2. What is the Incremental cost-effectiveness ratio (ICER): the
difference in costs / difference in effectiveness of clozapine treatment
compared to olanzapine treatment?
Secondary research questions: 1. Are there differences in direct and indirect
medical costs and non-medical costs between clozapine treatment and olanzapine
treatment? 2. Are there differences in effectiveness of clozapine treatment
compared to olanzapine treatment in: psychopathology, adverse effects,
compliance, drop out rate, psychosocial functioning and quality of life?
Study design
A 6 month multi-centre randomized, double blind study
Intervention
clozapine flexible dose 200-600 mg, olanzapine flexible dose 10 mg-30 mg
Study burden and risks
Burden: Patients will be randomly allocated to receive clozapine or olanzapine.
One extra session is needed to inform patients on the study design and
procedure. Four extra sessions are needed to assess baseline and outcome data.
Risk: There is a risk on adverse effects related to the treatment with
clozapine or olanzapine. Careful clinical procedures will be performed to
detect adverse effects and respond to them as needed. To keep the blinding it
is necessary to perform the same routine blood monitoring in both treatment
groups. Some extra blood samples will be taken for future research on proteins,
which may function as biological marker for treatment. Benefit: study
medication may be associated with favourable effects.
Meibergdreef 5
1105 AZ Amsterdam
NL
Meibergdreef 5
1105 AZ Amsterdam
NL
Listed location countries
Age
Inclusion criteria
Eligible for the study are in- and outpatients age 18 to 50, meeting DSM-IV criteria for schizophrenia, schizoaffective - or schizophreniform disorder and substance abuse or dependence based on the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders (SCID-P).
Patients that are admitted under authority of the court should also be included, since this group embodies a very large percentage of the targetgroup.
Patients should be able to understand the study information and procedures and give informed consent.
Exclusion criteria
- Pregnancy
- Lactating women
- Female subject without adequate contraception
- Known hypersensitivity to clozapine, olanzapine or ingredients used in these tablets
- Concomitant daily use of any antipsychotic other drug than clozapine or olanzapine (crisis intervention medication excepted)
- Use of depot antipsychotics in the three months prior to inclusion
- Narrow-angle glaucoma
- Known neurological or endocrine disease interfering with clozapine or olanzapine treatment
- Myeloproliferative disorder
- Uncontrolled epilepsy
- History of treatment with clozapine in the past 12 months during at least 4 months at therapeutic serum levels
- Paralytic ileus
- Current leukocyte level lower than 3.5 x 10 9/l
- Current neutrophilic granulocyte level lower than 2.0x 10 9/l
Design
Recruitment
Medical products/devices used
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| EudraCT | EUCTR2008-005019-16-NL |
| CCMO | NL24882.018.08 |