Search Results for: cyp2c

Proof-of-Concept for Bedside Rapid Genotyping Test of CYP2C19

A new point-of-care test can rapidly identify people with a common genetic variant associated with impaired clopidogrel function. The authors claim that this is the first study to demonstrate the feasibility of delivering a genetic test at bedside. In an article published online in the Lancet, Jason Roberts and colleagues report on a new point-of-care test that can…

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Meta-Analysis Examines Risk Associated with CYP2C19 Genotypes

There has been widespread debate and disagreement over the clinical significance of people with reduced function CYP2C19 genotypes who take clopidogrel. In an effort to shed light on the topic, Jessica Mega and colleagues analyzed data from 9685 patients enrolled in nine clinical trials. Some 26% of patients had 1 reduced-function allele, and 2% had 2…

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Zombie Lab Sues Former Execs, Owners, And Sales Force

–Yet more fallout from the catastrophic bankruptcy of HDL Lab The Zombie Lab case just got even messier. Last Friday the trustee for the bankrupt Health Diagnostic Laboratory (HDL) filed a massive lawsuit against the former executives, owners, sales force members, and others who profited from HDL. The 205-page lawsuit includes a detailed narrative of…

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Ticagrelor Joins Clopidogrel And Prasugrel In Updated NSTEMI Guidelines

Ticagrelor (Brilinta, AstraZeneca) gains equal standing with prasugrel (Effient, Lilly) and clopdiogrel in the newly released focused update of the ACCF/AHA guidelines for unstable angina and non-ST-elevation myocardial infarction (NSTEMI). The change had been widely anticipated since last year’s FDA approval of ticagrelor. “We have put it on equal footing with two other antiplatelet medications,…

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Failure of Another Trial Testing Guided Antiplatelet Therapy Prompts Debate

Updated, Saturday, April 7 Yet another trial has failed to prove the hypothesis that guided antiplatelet therapy with platelet function testing or genetic testing improves outcomes. Although there has been no public announcement so far, the TARGET-PCI (Thrombocyte Activity Reassessment and GEnoTyping for PCI) was suspended last October, according to the TARGET-PCI page on ClinicalTrials.Gov….

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Nissen and Topol Clash Over Genetics and Personalized Medicine

Steve Nissen and Eric Topol, former colleagues and collaborators, have staked out opposite positions on the future of medicine. Topol has been a leading advocate for genomics and personalized medicine, while Nissen has now publicly questioned whether the enthusiasm for these technologies has outpaced their value in medicine today. In an editorial in JAMA, Nissen writes…

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Clopidogrel Testing Comes Under Fire

The phenomenon of clopidogrel resistance has been much discussed, but no consensus has emerged about the best, or any, response to the problem. Now a review published in JAMA finds no clinically relevant relationship between the CYP2C19 genotype  and cardiovascular events. Michael Holmes and colleagues performed a meta-analysis of 32 studies involving CYP 2C19 genotyping and more than 42,000 patients. In…

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ELEVATE TIMI 56: One New Piece of the Clopidogrel Puzzle

Tripling the maintenance dose of clopidogrel in most but not all patients with a common genetic variation will lower platelet reactivity to levels achieved in patients without the variation, according to results of the ELEVATE TIMI 56 trial. The finding helps solve one piece of the clopidogrel puzzle, but does not provide a path to…

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Genetic and Clinical Factors Linked to Stent Thrombosis

French researchers have identified several genetic and clinical factors independently tied to early stent thrombosis. In a report published in the Journal of the American Medical Association, Guillaume Cayla and colleagues performed a case-control study comparing 123 patients with definite early stent thrombosis with 246 matched controls without stent thrombosis. The researchers found 3 genes…

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Updated Unstable Angina/NSTEMI Guidelines Released by ACC & AHA

The AHA and ACC have released a focused update of the 2007 guidelines for the management of unstable angina and NSTEMI. The guidelines incorporate new information from recent clinical trials, and deal with controversial topics such as the timing and role of invasive therapy, the choice of antiplatelet agents, and the use of platelet-function and…

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Study Finds No Evidence for Clopidogrel-Omeprazole Interaction

A large clinical trial has found no evidence that omeprazole interferes with the cardiovascular efficacy of clopidogrel. COGENT (Clopidogrel and the Optimization of Gastrointestinal Events Trial) randomized 3873 patients eligible for dual antiplatelet therapy to receive aspirin, clopidogrel, and either omeprazole or placebo. The COGENT investigators had planned to enroll 5000 patients, but the trial…

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ESC: genetic substudies of large trials question value of clopidogrel genotyping

Genetic substudies across a broad range of large clinical trials that used clopidogrel  raise questions about the clinical utility of clopidogrel genotyping. The substudies come from large and important trials like PLATO, TRITON-TIMI 38, CURE, and ACTIVE A….

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Topol vs Gurbel: experts split on routine genotyping for DAPT

Routine genotyping to guide dual-antiplatelet therapy (DAPT) seems like a great idea. After all, argue Damani and Topol in a Viewpoint in JACC, the arguments are overwhelming, and the consequences of not rushing to adopt the new technique are dire. They write that loss-of-function and gain-of-function variants of CYP2c19 are extremely common, and are “the root…

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Plavix label gets black box warning about poor metabolizers

The FDA announced today that it had added a boxed warning to the Plavix (clopidogrel) label, warning patients and doctors that the drug may be less effective in people who are unable to metabolize the drug and convert it to its active form. The FDA said that healthcare professionals “should consider use of other anti-platelet…

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FDA issues public health advisory on interaction between clopidogrel and omeprazole

Updated: The FDA has issued a public health advisory to highlight updated safety information regarding an interaction between clopidogrel (Plavix) and omeprazole. The label change, which was made on Friday, was reported first by CardioBrief yesterday. An FDA official explained that the label changes were based on data from a new study performed by the…

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New warnings added to Plavix (clopidogrel) label

Several new warnings have been added to the Plavix (clopidogrel) label. The new warnings are for reduced effectiveness due to impaired CYP2C19 function and for co-adminstration of the drug with omeprazole, which can reduce the pharmacologic activity of clopidogrel….

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Medco launches 14,000 patient head-to-head observational comparison of clopidogrel and prasugrel

Medco announced today that it is launching a large head-to-head prospective, observational study comparing clopidogrel (Plavix) and prasugrel (Effient) in more than 14,000 patients. The study, GeCCO (Genotype Guided Comparison of Clopidogrel and Prasugrel Outcomes Study), is designed to assess whether clopidogrel given to patients who are CYP2C19 extensive metabolizers is noninferior to prasugrel on the…

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JAMA: researchers identify genetic variation that hinders clopidogrel effectiveness

Researchers in Baltimore have identified a genetic variation that appears to have a powerful dampening effect on the antiplatelet efficacy of clopidogrel. Results of the study, along with an accompanying editorial by Deepak Bhatt, appear in JAMA….

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FDA approves prasugrel!

The FDA has approved prasugrel (Effient) to reduce the risk of MI in ACS patients undergoing PCI. Lilly had hoped to claim a broader indication for the drug. The drug’s labeling will include a boxed warning alerting physicians that the drug can cause significant, sometimes fatal, bleeding, according to the FDA press release. “The drug…

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Prasugrel not affected by common CYP genetic variations

Prasugrel efficacy does not appear to be susceptible to some common genetic variations, according to a new substudy of 1,466 patients enrolled in the TRITON-TIMI 38 study published in Circulation. Although both prasugrel and clopidogrel require cytochrome P450 enzymes for activation, the substudy found that prasugrel did not appear to be affected by a common…

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FDA announces ongoing safety review of clopidogrel

In an “early communication” posted on its website, the FDA announced today that it was examining the safety of clopidogrel….

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