HJAR Jul/Aug 2021

32 JUL / AUG 2021 I  HEALTHCARE JOURNAL OF ARKANSAS CHILDREN’S HEALTH COLUMN CHILDREN’S HEALTH What is Precision Medicine? PrecisionMedicine(PM)is“theapproach to preventing and treating disease taking the individual patient’s genetic, environmental and lifestyle determinants of health into consideration.” 1 Sir William Osler once said, “It is much more important to know what sort of a patient has a disease than what sort of a disease a patient has.” 2 A strong movement to advancemedical care to amore personal level is underway. Truly customized medicine is no longer a theoretical concept. It is now a clinical reality. Lee Hood coined the term “P4Medicine” to capture the growing importance of the patient’s voice in medicine. 3 The four P’s in this concept are predictive, preventive, participatory and personalized healthcare. The latter term refers to the use of individual patient data to direct the care specific to a single patient. Several terms have been used to describe this practice, including precision medicine or individualized medicine, but the term personalized medicine has been the most widely used. In January 2015, at a State of the Union address, President Barack Obama announced a call to action to promote the Precision Medicine Initiative. This initiative has the ultimate goal of moving the United States into the erawhere medical treatment will be tailored to each patient. In its essence it has been distilled Dutch Pharmacogenetic Working Group (DPWG) 10 and PharmGKB. 11 The PM team identified 174 clinically actionable single nucleotide polymorphisms (SNPs) located in 23 genes or gene variants that metabolize about 66 pediatric drugs. This test panel, called Clinical PGx Panel, is now available for patient PGx testing with both pediatric and adult guidance. Clinician Survey The PM group surveyed hospital clini- cians about PGx. 12 The survey showed that few physicians had previously ordered a pharmacogenomic test outside of the or- ganization; however, a high percentage (91.6%) were eager to learn more about pharmacogenomics. It was encouraging that almost all (99.2%) of survey partici- pants realized that a patient’s genetic pro- file could influence his or her response to drug therapy. In the near future, we feel that clinicians and patients will be more comfortable with the pharmacogenomic guidance. Validation of a Clinical Pharmacogenomics Test The PGx test that is running the 174 SNP PGx Panel underwent extensive validation and is performed in the CLIA-approved Clinical Pathology Lab at Arkansas Children’s. The test is being performed using a QuantStudio 12K Flex Real-time PCR instrument along with a custom 192-format genotyping Open Array (OA) 13 plate. G. Bradley Schaefer, MD Arkansas Children’s Research Institute Department of Pediatrics University of Arkansas for Medical Sciences down to “the right drug at the right dose for the right person.” It is the shift from “which treatment is best for this disease” to “which treatment is best for this patient.” What is Pharmacogenomics? Pharmacogenomics (PGx) aims to individualize treatment options for every patient based on their genetic information. 4,5,6 PGx is a growing field within PM and is rapidly advancing the discovery, translation and implementation of improved healthcare by touching and improving the care of every patient. 7 Each person responds to drugs differently because of underlying individual genetic differences. Currently, the Food and Drug Administration (FDA) has black box warning labels on more than 286 drugs that require biomarker information for therapeutic decision making and for the purpose of avoiding adverse drug reactions (ADRs). 8 PGx uses information from an individual’s genetic makeup to choose the drugs that will work ideally for each patient. In 2018, the PM team at Arkansas Children’s reviewed more than 43,000 pharmacy records to identify prescribing practices associated with drugs that have pediatric PGx guidance per clinically based guidelines from the FDA, the Clinical Pharmacogenomics Implementation Consortium (CPIC), 9 the PRECISION MEDICINE I N A R K A N S A S