11/19/2013 - Which antiplatelet medication is best after a coronary stent? The costly and potential life-or-death question lingers after most of the 600,000 angioplasties performed every year in the United States. The answer may lie in your genes, but professional cardiovascular societies and many working cardiologists question the U.S. Food and Drug Administration’s recent recommendation that patients undergo genetic testing before taking Plavix (clopidogrel bisulfate).
NorthShore University HealthSystem (NorthShore) is partnering with Mayo Clinic as the only site in Illinois participating in the Tailored Antiplatelet Therapy to Lessen Outcomes after Percutaneous Coronary Intervention (TAILOR-PCI) Study. The study examines whether prescribing heart medication based on a patient’s CYP2C19 genotype will help prevent heart attack, stroke, unstable angina, and cardiovascular death in patients who undergo percutaneous coronary intervention, commonly called angioplasty.
“This is an important study because it will allow us to collaborate with the Mayo Clinic in therapies that are patient centered by offering the greatest chances to benefit each one of our patients,” says Jorge Saucedo, MD, Division Head of Cardiology at NorthShore. “What we’re trying to do with TAILOR-PCI is to individualize the better antiplatelet therapy for patients with coronary stents based on their genotype. The future of medicine is that of giving each one of our patients the medications that work best for them based on their genotype and the TAILOR-PCI is one of the first studies in the cardiovascular arena to do so.”
Antiplatelet medication reduces the risk of heart attack, unstable angina, stroke, and cardiovascular death after stent placement by reducing the possibility of blood clots around the surgical site. Plavix, however, remains ineffective until the liver enzyme CYP2C19 metabolizes the drug into its active form. Some alternative medications, including Brilinta (ticagrelor), do not require activation through the same genetic pathway.
“The current standard of care after angioplasty is to prescribe clopidogrel for one year, regardless of a person’s individual genotype, even though we have known for several years that variation in the CYP2C19 gene may diminish the benefit from the drug,” says Naveen Pereira, M.D., a Mayo Clinic cardiologist and principal investigator of TAILOR-PCI. “What we don’t know — and why there is such confusion in the cardiovascular community — is how these genetic changes affect long-term clinical outcomes and whether we can decrease overall health care costs.”
Another additional benefit of the study will be creation of a coronary artery disease biobank containing DNA samples from the study’s 5,300 participants. Researchers at NorthShore and other participating sites can mine these samples and use genomic sequencing technologies to help further medicine’s understanding of the origins of and risk factors for coronary heart disease.
Heart disease is the number one killer of men and women in the United States, and up to one-third of patients currently taking Plavix (up to half of some Asian populations) have a genomic variant implicated in diminished drug response. Study teams at 15 hospitals in three countries have teamed up to enroll 5,300 patients into TAILOR-PCI and deliver results in three years. The Pharmacogenomics Program in the Center for Individualized Medicine administers this study.