Implementation of a pharmacogenetic panel-based test for pharmacotherapy-based supportive care in an adult oncology clinic

Abstract

The University of Florida Health conducted a pragmatic implementation of a pharmacogenetics (PGx) panel-based test to guide medications used for supportive care prescribed to patients undergoing chemotherapy. The implementation was in the context of a pragmatic clinical trial for patients with non-hematologic cancers being treated with chemotherapy. Patients were randomized to either the intervention arm or control arm and received PGx testing immediately or at the end of the study, respectively. Patients completed the MD Anderson Symptom Inventory (MDASI) to assess quality of life (QoL). A total of 150 patients received PGx testing and enrolled in the study. Clinical decision support and implementation infrastructure were developed. While the study was originally planned for 500 patients, we were underpowered in our sample of 150 patients to test differences in the patient-reported MDASI scores. We did observed a high completion rate (92%) of the questionnaires; however, there were few medication changes (n = 6 in the intervention arm) based on PGx test results. Despite this, we learned several lessons through this pragmatic implementation of a PGx panel-based test in an outpatient oncology setting. Most notably, patients were less willing to undergo PGx testing if the cost of the test exceeded $100. In addition, to enhance PGx implementation success, reoccurring provider education is necessary, clinical decision support needs to appear in a more conducive way to fit in with oncologists' workflow, and PGx test results need to be available earlier in treatment planning.

Trial registration: ClinicalTrials.gov NCT03924557.

FIGURE 1

Consort diagram of patients. Patients were screened for eligibility, if they met criteria they were approached about participating in the study. If the patient agreed and provided informed consent, they were randomized (n = 150) to either the intervention or control arm. Patients who completed a baseline MDASI were included in the analysis.

FIGURE 2

Patients on relevant supportive care medications. Supportive care medications impacted by pharmacogenetic results include select serotonin reuptake inhibitors (SSRIs) (i.e., paroxetine, fluvoxamine, sertraline, escitalopram, and citalopram), ondansetron, proton pump inhibitors (PPIs), select opioids (i.e., codeine, tramadol, hydrocodone, and oxycodone), warfarin, and voriconazole. Patients on these medications are shown in arm. Within each relevant grouping of medications, it is described the number of patients who had an actionable pharmacogenetic result that corresponded with that specific medication class (e.g., CYP2D6 for opioids). Definitions of actionable gene–drug pairs can be found in Table S1.