TAILOR-PCI misses endpoint but still provides valuable insights

Although it missed its primary endpoint of a 50% reduction in cardiovascular (CV) events at 1 year, the TAILOR-PCI trial demonstrated a 34% reduction in CV events, alongside a statistically significant 40% reduction in the total number of events per patient receiving genetically-guided treatment versus patients receiving standard treatment [1].

TAILOR-PCI, presented by Prof. Naveen Pereira (Mayo Clinic, USA), is the largest trial to date to investigate the clinical utility of using genetic testing to detect the clopidogrel loss-of-function (LOF) genotype to guide antiplatelet therapy in patients undergoing percutaneous coronary intervention (PCI). The trial enrolled 5,302 patients who had had PCI with stenting. Patients received standard antiplatelet therapy with clopidogrel 75 mg/day without genetic testing or antiplatelet therapy prospectively guided by genotyping for the clopidogrel reduced-function CYP2C19 alleles. Of the tested patients, 35% was found to have the clopidogrel LOF variant. They received ticagrelor 90 mg daily, whereas patients without the LOF variant were treated with clopidogrel. The primary composite endpoint consisted of CV death, myocardial infarction, stroke, definite or probable stent thrombosis, and severe recurrent ischaemia.

After 1 year, 4% of patients receiving genetically guided treatment experienced a primary endpoint event versus 5.9% of patients who were treated conventionally (adjusted HR 0.66; 95% CI 0.43- 1.02; P=0.56), showing a neutral result for the primary endpoint. An exploratory analysis indicated that there was a lower rate of 40% associated with those who were genotyped (HR 0.60; 95% CI 0.41-0.89; P=0.011). Interestingly, the rate of adverse events was significantly reduced by 79% in the first 3 months of treatment among patients who received genetically-guided therapy compared with those who did not. Prof. Pereira pointed out that, as the risk of adverse events is highest immediately after PCI, the potential benefit of genetically-guided therapy has the largest impact in this particular period. The study might have been underpowered as a result of recent improvements in care, such as the use of drug-coated stents, which may have reduced the expected rates of adverse events. Further studies are planned, including a cost-effectiveness analysis of genetically-guided therapy based on long-term follow-up of these patients.

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   1. Pereira NL, et al. Abstract 402-12. ACC/WCC 28-30 March 2020.

Posted on 7 September, 20201 May, 2024