A Real-World Perspective on Pharmacogenetics in Clinical Practice

The uptake of pharmacogenetics, the science of using genetic markers to assess the risk-benefit profile of a particular pharmacotherapy, in everyday clinical practice has been hampered by the paucity of real-world clinical effectiveness data as well as the lack of an effective care delivery system providing access to tools and knowledge for making decisions based on pharmacogenetic information. Medco manages pharmacy benefits of 65 million individuals in the United States – a service that is enabled through the only fully electronically-wired health care environment in this country, the pharmacies. Therefore, the identification of patients that could benefit from the use of a pharmacogenetic test can take place in real-time and access to the test can be facilitated at the pharmacy level. We are utilizing this real-time, real-world environment to (1) conduct research that helps us understand the clinical and economical impact of the use of pharmacogenetic tests and (2) deploy commercial clinical programs of such tests have a proven benefit for patients. For example, in collaboration with the Mayo clinic, we have conducted a prospective observational cohort study assessing the effectiveness of genetic testing for CYP2C9 and VKORC1 for patients new to warfarin therapy and found a 28 percent reduction in hospitalization in the cohort that received information about their sensitivity to warfarin based on their genetic profile. We then implemented a clinical program, now subscribed to by >300 Medco clients covering approximately 15 million lives, and were able to show a significant increase in the uptake of this test in clinical practice (baseline uptake 0.5 percent vs. 15 percent in the program). This is the first time that a translation of a pharmacogenetic test into clinical practice, based on real-world clinical effectiveness data has been immediately and effectively implemented: today, thousands of patients are receiving access to this pharmacogenetic test which is fully managed and reimbursed. In addition to warfarin, we now have several other tests that are being managed under our expanded health care programs. However, given the increasing number and complexity of these tests as well as the increasing number of therapies that are competing with each other, the need for demonstrating value in a comparative manner is critical to assure the best possible effectiveness of both, test and drug. For example, prasugrel (Effient®) is a new drug competing with clopidogrel (Plavix®), dabigatran (Pradaxa®) is a new drug competing with warfarin: we launched a large comparative effectiveness study and set up a registry to address the question of how these new drugs compare, respectively. These and other examples from research and the translation of this research into the clinical practice will be presented.