Can CYP2C19 genotyping improve antiplatelet therapy efficacy in real-life practice? Recent advances.

Clopidogrel remains the most widely used P2Y12 receptor inhibitor worldwide and is often used in combination with aspirin for secondary prevention in patients with arterial disease. The drug is associated with a wide response variability with one on three patients exhibiting little or no inhibition of adenosine diphosphate-induced platelet aggregation. It is a prodrug that is mainly metabolized by hepatic cytochrome P450 (CYP) 2C19. Patients who carry a CYP2C19 loss-of-function (LoF) allele have reduced metabolism of clopidogrel that is associated with reduced platelet inhibition compared to non-carriers that is associated with increased risk for thrombotic event occurrences, particularly, stent thrombosis. The United States Food and Drug Administration (US FDA) issued a black box warning in the clopidogrel label highlighting the importance of presence of CYP2C19 LOF allele during the insufficient metabolism of clopidogrel and availability of other potent P2Y12 inhibitor for the treatment in CYP2C19 poor metabolizers. Clinical trials have conclusively demonstrated greater anti-ischemic benefits of prasugrel/ticagrelor in the treatment of patients carrying the CYP2C19 LoF allele. However, uniform use of these more potent P2Y12 inhibitors has been associated with greater bleeding and cost, and lower adherence. The latter information provides a strong rationale for personalizing P2Y12 inhibitor therapy based on the laboratory determination of CYP2C19 genotype. However, cardiologists have been slow to take up pharmacogenetic testing possibly due to lack of provider and patient education, clear cardiology guidelines and, and lack of positive results from adequately sized randomized clinical trials. However, current evidence strongly supports genotyping of patients who are candidates for clopidogrel. Physicians should strongly consider performing genetic tests to identify LoF carriers and treat these patients with more pharmacodynamically predictable P2Y12 inhibitors than clopidogrel.

P2Y12 Inhibitor Monotherapy After Short-Term Dual Antiplatelet Therapy in Acute Coronary Syndrome.

Recent studies have shown similar safety and efficacy of short-term dual antiplatelet therapy (DAPT) followed by P2Y12 inhibitor (P2Y12i) monotherapy when compared with standard DAPT. However, the optimal DAPT duration and regimen in acute coronary syndrome (ACS) patients who underwent percutaneous coronary intervention is still unclear. Online databases were searched for randomized controlled trials evaluating P2Y12i monotherapy after short DAPT (≤3 months) versus standard DAPT (≥12 months) in ACS patients. The outcomes of interest were all-cause death, cardiovascular death, myocardial infarction, stent thrombosis, target-vessel revascularization, and major bleeding. Random-effects model was used to calculate pooled odds ratios (OR) and 95% confidence intervals (CI). Six randomized controlled trials with a total of 23,884 patients (n = 11,904 P2Y12i monotherapy, n = 11,980 standard DAPT) were included. Compared with standard DAPT, P2Y12i monotherapy after short DAPT was associated with similar odds of all-cause death (OR 0.86, 95% CI 0.65 to 1.12, p = 0.26) and cardiovascular death (OR 0.75, 95% CI 0.43 to 1.29, p = 0.29) at 1 year. Similarly, there were no significant differences in rates of myocardial infarction (OR 1.09, 0.83 to 1.43, p = 0.53), stent thrombosis (OR 1.09, 95% CI 0.71 to 1.67, p = 0.70) and target-vessel revascularization (OR 0.81, 95% CI 0.65 to 1.01, p = 0.07) between the P2Y12i monotherapy and standard DAPT arms. The P2Y12i monotherapy group had significantly lower major bleeding (OR 0.49, 95% CI 0.38 to 0.64, p < 0.001) when compared with standard DAPT. In conclusion, in patients with ACS who underwent percutaneous coronary intervention, P2Y12i monotherapy after short DAPT significantly reduces bleeding without increasing ischemic risk when compared with standard DAPT therapy.

Safety and efficacy of glucagon-like peptide-1 receptor agonists on cardiovascular events in overweight or obese non-diabetic patients.

BACKGROUND: Randomized controlled trials (RCTs) have shown variable cardiovascular (CV) outcomes in overweight or obese patients without diabetes mellitus (DM) who are treated with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) vs. placebo. We conducted a meta-analysis of the available studies. METHODS: Online databases were searched for RCTs comparing GLP-1 RA to placebo in overweight or obese non-diabetic patients. The clinical endpoints of interest were major adverse CV events (MACE), CV death, all cause death, myocardial infarction (MI), stroke, revascularization, total adverse events and their subtypes. Pooled odds ratios (OR) and 95 % confidence intervals (CI) were calculated using a random-effects model. RESULTS: A total of 10 RCTs with 29,325 patients (n = 16,900 GLP-1 RA, n = 12,425 placebo) were included. The mean age was 48 years and 34 % of patients were men. As compared with placebo, the GLP-1 RA group was associated with significant reduction of MACE (OR 0.79, 95 % CI 0.71-0.89, p < 0.0001), all cause death (OR 0.80, 95 % CI 0.70-0.92, p = 0.002), MI (OR 0.72, 95 % CI 0.61-0.85, p = 0.0001) and revascularization (OR 0.76, 95 % CI 0.67-0.86, p < 0.0001), without any differences in CV death or stroke. Total adverse events, gastrointestinal and gallbladder-related disorders were higher in the GLP-1 RA group, with a similar rate of renal adverse events, malignant neoplasms and acute pancreatitis to placebo. CONCLUSION: In overweight or obese patients without DM, patients treated with GLP-1 RAs had significantly reduced MACE, all cause death, MI and revascularization when compared with placebo.