RT Journal Article SR Electronic T1 Cost-effectiveness of pharmacogenomic-guided treatment for major depression JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E1499 OP E1508 DO 10.1503/cmaj.221785 VO 195 IS 44 A1 Ghanbarian, Shahzad A1 Wong, Gavin W.K. A1 Bunka, Mary A1 Edwards, Louisa A1 Cressman, Sonya A1 Conte, Tania A1 Price, Morgan A1 Schuetz, Christian A1 Riches, Linda A1 Landry, Ginny A1 Erickson, David A1 McGrail, Kim A1 Peterson, Sandra A1 Vijh, Rohit A1 Hoens, Alison M. A1 Austin, Jehannine A1 Bryan, Stirling YR 2023 UL http://www.cmaj.ca/content/195/44/E1499.abstract AB Background: Pharmacogenomic testing to identify variations in genes that influence metabolism of antidepressant medications can enhance efficacy and reduce adverse effects of pharmacotherapy for major depressive disorder. We sought to establish the cost-effectiveness of implementing pharmacogenomic testing to guide prescription of antidepressants.Methods: We developed a discrete-time microsimulation model of care pathways for major depressive disorder in British Columbia, Canada, to evaluate the effectiveness and cost-effectiveness of pharmacogenomic testing from the public payer’s perspective over 20 years. The model included unique patient characteristics (e.g., metabolizer phenotypes) and used estimates derived from systematic reviews, analyses of administrative data (2015–2020) and expert judgment. We estimated incremental costs, life-years and quality-adjusted life-years (QALYs) for a representative cohort of patients with major depressive disorder in BC.Results: Pharmacogenomic testing, if implemented in BC for adult patients with moderate–severe major depressive disorder, was predicted to save the health system $956 million ($4926 per patient) and bring health gains of 0.064 life-years and 0.381 QALYs per patient (12 436 life-years and 74 023 QALYs overall over 20 yr). These savings were mainly driven by slowing or avoiding the transition to refractory (treatment-resistant) depression. Pharmacogenomic-guided care was associated with 37% fewer patients with refractory depression over 20 years. Sensitivity analyses estimated that costs of pharmacogenomic testing would be offset within about 2 years of implementation.Interpretation: Pharmacogenomic testing to guide antidepressant use was estimated to yield population health gains while substantially reducing health system costs. These findings suggest that pharmacogenomic testing offers health systems an opportunity for a major value-promoting investment.See related article at www.cmaj.ca/lookup/doi/10.1503/cmaj.231441