We check lipids to minimize cardiovascular events. We mandate mammograms, prostate exams, colonoscopies, and bone density tests in an attempt to minimize adverse health events. And yet, healthcare still has not caught on to preemptive pharmacogenomic testing. Despite the fact that 90% of conventional and top-selling blockbuster medicines only work for 30-50% of patients, and adverse drug events may be responsible for more than $30 billion in healthcare costs annually, modern medicine is still chasing its tail. The utility of pharmacogenomics is now well-recognized in patients who have failed multiple treatment options for a disease state. Companies gladly cover testing in such patients to determine an appropriate choice of therapy. But what about pharmacogenomic testing to avoid failure of preventive therapy? Testing also can determine if a preventive medication will provide the protection for which it is prescribed. The purpose of many medications such as clopidogrel (Plavix) is to prevent future adverse cardiac and cerebrovascular events; unfortunately, without testing, the only way a patient will ever know it is ineffective is when he or she experiences such a life-threatening event.
Testing also can determine if a preventive medication will provide the protection for which it is prescribed.
This January, the Clinical Pharmacogenetics Implementation Consortium released new guidelines indicating that CYP2C19 intermediate and poor metabolizers are at increased risk for adverse cardiac and cerebrovascular events when prescribed clopidogrel (Plavix) for cardiovascular indications. This recommendation impacts a large portion of the population, and most individuals are unaware of their status. Approximately 30% of the US population carries either 1 or 2 loss-of-function CYP2C19 alleles and are classified as intermediate or poor metabolizers respectively (in other words, drugs will metabolize differently than anticipated). Based on the documented probability estimates, preemptive pharmacogenetic testing is encouraged for every patient who will undergo therapy with any drug whose metabolism depends on CYP2C19 expression and should be considered in case of treatment resistance or serious adverse effects. The irony of this suggestion is that patients cannot predict when an emergent need for antiplatelet therapy will present itself. Delaying pharmacogenomic testing until after the medication has already failed to prevent a cardiovascular event may be too little, too late.
Is it time to consider preemptive pharmacogenomic testing? If you are interested in learning about the benefits pharmacogenomic testing may offer your organization or practice, please reach out to the Profero Team for in-depth guidance on valuation, strategy, and implementation!
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