Not all drugs are effective for all people. A drug that works well for one person may not be effective for another or may produce unwanted side effects. In the case of schizophrenia, for example, almost a third of patients (around 30%) fail to respond to antipsychotics, putting them at risk of ongoing and potentially dangerous symptoms and side-effects from medication that is ineffective at best and harmful at worst.
What is precision medication?
There is a growing move towards precision or personalised medication, which uses a person’s unique genetic makeup to identify the safest, most effective drugs to treat them. It is a step-change as up until now, the prescription of medications has been based on a trial and error approach.
Unfortunately, such an approach can lead to a delay in effective treatment which may lead to deterioration or worse. In the case of schizophrenia patients there is a risk of suicide, so any delay in effective treatment can have serious consequences.
At the Center for Biomarker Research and Precision Medicine at Virginia Commonwealth University, scientists recently carried out a study into people who had experienced psychosis for the first time. They studied 510 patients and measured their schizophrenia symptoms before and after a 12-week course of antipsychotic medication.
Scientists also calculated each patient’s polygenic risk score for schizophrenia, which is a predictor based on their unique DNA sequence. They found that the lower the polygenic risk score, the more likely they were to respond well to antipsychotic medication. Lower scores predicted a more successful outcome for three out of the four patient groups.
While previous studies have looked at the role of individual genes in determining how well people will respond to medication, this polygenic risk score study encompasses thousands of variants. Scientists believe this may be more helpful as antipsychotics work on many different places in the brain.
How this information could be used
In the future, such information could be used to predict how well patients will respond to antipsychotics. If a patient is predicted to respond poorly to drugs they could be offered alternative treatment, such as transcranial magnetic stimulation.
A research team in China analysed more than 3,000 people with schizophrenia who were prescribed antipsychotic medicine after their first psychotic episode.
They identified which patients experienced the most and the least improvement in their symptoms and then sequenced their genomes. This revealed a link between poor responses to the drugs and mutations in genes associated with glutamine transmission. This information may enable researchers to predict who will respond to drug treatment in the future and may be useful in the development of new drugs.
Schizophrenia is an important area of study for researchers into the link between genetics and medication because the condition has a significant genetic component.
Whether or not a person develops schizophrenia is 70-80% due to their genetic makeup and how well people respond to antipsychotics is believed to be 50% attributable to their genetics.
Other mental health conditions also have a significant genetic component including bipolar disorder and depression.
Genetic testing using Genecept Assay
Myogenes is a pioneer in the field of pharmacogenomics, which is the science of matching a person’s genetic code to the medications that are prescribed.
Our Genecept Assay tests for mental health conditions using a swab from the patient’s cheek.
It is used by doctors to identify which drugs will be effective for individual patients and what the optimum dosage will be.
It is increasingly being used in the treatment of serious mental health conditions, such as depression, anxiety, schizophrenia and many more mental health conditions, to ensure that patients get the treatment they need quickly and safely.