Clinical Pharmacology and Genomic Prescription Pathways: Toward a Paradigm Shift in Individualized Drug Therapy-A Review

Pharmacogenomics (PGx), a key pillar of precision medicine, enables drug therapy customization based on a patient’s genetic profile. Pharmacists, as experts in medication, are best placed to organize the use of PGx testing, interpretation, and decision-making about therapeutics in order to optimize therapeutic outcomes. This review identifies actionable gene-drug interactions in the form of CYP2C19-clopidogrel, DPYD-fluoropyridines, and TPMT/NUDT15-thiopurines, which have clinical implications for reducing adverse drug reactions and enhancing the effectiveness. It also explores the international situation of implementing PGx where high-income nations face fragmented data architecture, issues related to guideline harmonization, and lack of reimbursement, and low- and middle-income nations are characterized by poor infrastructure, high costs, and low genomic literacy. Some of the suggested solutions are the incorporation of decision-support tools into the electronic health record, pharmacy curriculum reformation, developing subsidized testing programs, and using AI/ML to support data interpretation. Pharmacists are becoming the primary contributors to precision medicine in the hospital, community and telehealth environment, and can become the solution to making PGx no longer a specialty service provided to a limited set of patients, but the default type of service in most places worldwide.