Genetic Testing in Psychiatry

Pharmacogenetics has developed substantially in the last twenty years. In many areas of medicine, clinicians now have access to genetic information that enables them to be much more precise when individualising therapy; with treatment choice, monitoring, and dosing informed by a specific analysis of a patient’s genetic profile.

In patients with schizophrenia, several aspects of the genetic profile have been shown to be important in determining outcomes in clozapine therapy. Psychiatric Genetic Testing Ltd (PGT) has created a suite of tests based on advances in pharmacogenetic research to provide clinicians with new insights to inform the use of clozapine in individual patients.

The Clozapine Test

Clozapine is the only effective treatment for people with treatment-refractory schizophrenia, defined as failed treatment attempts of adequate dose and duration with two other antipsychotics. Although the value of clozapine in these situations is widely acknowledged there is still a reluctance to prescribe and usage rates vary widely. This may mean long delays before treatment-refractory patients are offered clozapine, resulting in poor outcomes, exposure to potentially hazardous antipsychotic polypharmacy, unnecessary distress for patients, and avoidable healthcare costs. This reluctance may result from the clinical uncertainties that exist with clozapine, including the likelihood of response, the risks of adverse effects, or the optimal dosing for individual patients.