Pilot study of multi-gene pharmacogenetic testing for pain management in oncology palliative medicine.

Aim: We evaluated the application and clinical impact of multi-gene pharmacogenetic testing in oncology palliative medicine. Patients & methods: In a single-arm pilot trial, cancer patients with uncontrolled pain were assessed in a palliative medicine clinic at baseline and received pharmacogenetic testing. Results were used as applicable up to the final visit (day 30). Pain scores, opioid prescribing, and use of pharmacogenetic test results were collected. Results: In 75 patients, the median baseline pain score was 7/10. Of 54 evaluable at the final visit, 28 required opioid modifications and 19 had actionable genotypes, mostly CYP2D6. Pain improvement (≥2-point reduction) was higher than historical data (56 vs 30%; p < 0.001). There were no differences in pain improvement between those with and without actionable genotypes (61 vs 53%). Conclusion: Multi-gene testing identified actionable genotypes and may improve cancer pain.