Effect of Genotyping for CYP450 Polymorphisms Versus Intense Clinical Monitoring on Antipsychotic Drug Treatment

A Three-armed Randomised Controled Trial on the Effect of Genotyping for CYP450 Polymorphisms and Intense Clinical Monitoring on Antipsychotic Drug Treatment.

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00707382

Enrollment

311

Registered

2008-06-30

Start date

2008-02-29

Completion date

2011-12-31

Last updated

2012-02-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Schizophrenia

Keywords

Pharmacogenetics, Compliance, Antipsychotic drugs, Schizophrenia

Brief summary

The purpose of this study is to determine whether genotyping for CYP2D6 and 2C19 polymorphisms or intense clinical monitoring of treatment and adverse effects improves the antipsychotic treatment in patients with schizophrenia. This study is designed as a three-armed prospective randomized controlled clinical trial and includes 300 patients with schizophrenia. Patients are followed for a period of one year. During the study period the following effect measures are registered: * Time to discontinuation of all antipsychotic medications * Number of changes in medication dose * Number of changes in medication * Compliance (patients´ adherence to medical treatment) * Clinical symptoms * Adverse effects

Interventions

GENETIC(1) Genotyping for CYP4502D6 and 2C19 polymorphisms

In this study arm (1), the genotype information is given to the physician in charge of treatment and can be used to direct the pharmacological treatment according to local guidelines. In the guidelines the genotype is translated to the clinical designation normal, slow or fast metabolizer of CYP2D6 or normal or slow metabolizer of CYP2C19. Different treatment options for the different genotypes are described.

OTHER(2) Intense clinical monitoring

In this study arm (2) the genotype information is not revealed. The intervention consists of an intensified clinical monitoring of treatment effect, side effects and patient perspective. Staffpersonnel is trained in the use of a clinical manual that builds on a selection of validated questions from the Scale for the Assessment of Positive Symptoms (SAPS), Side effect score (Udvalg af Kliniske Undersøgelser (UKU) and Rating of Medical Influences (ROMI). The manual has to be used at least once in a quarter (every third month), which is monitored by the study personnel. Data registered by the patients primary contact person are not used as outcome measures in the study but only as intervention tool for the optimisation of the medical antipsychotic treatment.

OTHER(3) Control

In this studyarm (3), (Control) treatment followed usual local practice. The genotype information was not revealed.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

DIAGNOSTIC

Masking

QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Diagnosed with schizophrenia * Able to give written informed consent

Exclusion criteria

* Genotyped prior to inclusion

Design outcomes

Primary

Measure	Time frame
Time to discontinuation of initial antipsychotic treatment	one year

Secondary

Measure	Time frame
Compliance	one year

Countries

Denmark

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 16, 2026