Genetic testing for CYP2D6 and CYP2C19 suggests improved outcome for antidepressant and antipsychotic medication

• Published in: Psychiatry research Vol. 279; pp. 111 - 115
• Main Authors: Walden, Lucas M., Brandl, Eva J., Tiwari, Arun K., Cheema, Sheraz, Freeman, Natalie, Braganza, Nicole, Kennedy, James L., Müller, Daniel J.
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.09.2019
• Subjects: Adult; Alleles; Antidepressive Agents - adverse effects; Antidepressive Agents - therapeutic use; Antipsychotic Agents - adverse effects; Antipsychotic Agents - therapeutic use; Clinical; Cytochrome P-450 CYP2C19 - genetics; Cytochrome P-450 CYP2D6 - genetics; Depressive Disorder - drug therapy; Drug-Related Side Effects and Adverse Reactions - genetics; Female; Genetic Testing; Genetics; Genotype; Humans; Male; Middle Aged; Personalized medicine; Pharmacogenetics; Psychiatric medication; Psychotic Disorders - drug therapy; Treatment Outcome; Psychiatric medication; Clinical; Genetics; Pharmacogenetics; Personalized medicine
• ISSN: 0165-1781; 1872-7123; 1872-7123
• DOI: 10.1016/j.psychres.2018.02.055

Individuals carrying genetic variants that result in non-extensive CYP2D6 and CYP2C19 enzyme activity seem to be more prone to non-response and side-effects of psychotropic medications. Therefore, tailoring prescriptions using genetic information may improve patient outcomes. This study examined treatment outcome in psychiatric care after CYP2D6 and CYP2C19 genetic information was provided to patients and physicians. CYP2D6 and CYP2C19 genotyping, assessment of side effects and medical histories were obtained from 80 subjects who were prescribed either antidepressant or antipsychotic medications. Our measure of outcome was mainly physicians’ opinions however UKU side effects scores were also used. For CYP2D6, we calculated an activity score based on genotype and psychiatric medications. Correlation analysis was performed for CYP2D6 activity scores and UKU scores. Overall, we received supportive responses from physicians who enrolled patients in our study. Notably, while almost every fourth physician reported improvement in patient outcome, not a single physician indicated that their patient's symptoms worsened after they had used a pharmacogenetic report to guide treatment. We did not observe statistically significant differences in side effects. Overall, our results suggest improved patient outcome following pharmacogenetic testing; nonetheless, more research is required to assess the exact benefit of pharmacogenetics in clinical practice. •This study assessed treatment outcome in psychiatric practice following pharmacogenetic testing for CYP2D6 and CYP2C19.•Outcome was measured by physicians’ opinions of their patients’ outcome following treatment changes.•Our secondary measure of clinical outcome was based on differences in side effect scores across metabolic activity groups.•Nearly one in four psychiatrists reported some degree of clinical improvement in their patient’s outcome.•Not a single physician stated that their patient’s clinical condition worsened.