Characterizing high-risk enrollment criteria and impact on clinical outcomes in a large randomized clinical trial: Insights from the TWILIGHT trial

Background: The TWILIGHT trial showed that, among high-risk patients who underwent percutaneous coronary intervention (PCI) and were event-free at 3 months, ticagrelor monotherapy versus ticagrelor plus aspirin reduced bleeding without increasing ischemic events. Methods: This posthoc analysis describes the risk profiles and outcomes of patients enrolled in the TWILIGHT trial. The primary outcome was Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding, and the key secondary outcome was a composite of death, myocardial infarction, or stroke within 1 year after randomization. Results: The proportion of patients (n = 7,119) fulfilling ≤ 3, 4, 5, or ≥ 6 risk factors was 21.5%, 32.7%, 27.4%, and 18.4%, respectively. Troponin-positive acute coronary syndrome (ACS) was the most prevalent clinical criterion (64.9%), and multivessel disease (MVD) was the most prevalent angiographic criterion (66.5%). The most frequent intersection of criteria was the combination of troponin-positive ACS, atherosclerotic vascular disease, MVD, left main or proximal anterior descending lesion, and stent length > 30 mm. A stepwise increase in ischemic but not in bleeding risk was noted with an increasing number of high-risk criteria. Compared with ticagrelor plus aspirin, ticagrelor monotherapy reduced bleeding regardless of the number of risk factors (≤ 3-RF: 3.5% vs 5.8%, HR 0.59, 95% CI [0.38-0.93]; 4-RF: 3.7% vs 6.4%, HR 0.57, 95% CI [0.37-0.86]; 5-RF: 3.8% vs 8.6%, HR 0.44, 95% CI [0.29-0.66]; ≥ 6-RF: 5.3% vs 7.9%, HR 0.65, 95% CI [0.44-0.96]; p-interaction = .56) without significantly increasing the ischemic risk (≤ 3-RF: 1.6% vs 2.1%, HR 0.75, 95% CI [0.38-1.50]; 4-RF: 3.5% vs 2.2%, HR 1.58, 95% CI [0.91-2.75]; 5-RF: 4.1% vs 5.0%, HR 0.80, 95% CI [0.51-1.24]; ≥ 6-RF: 6.7% vs 6.9%, HR 0.98, 95% CI [0.67-1.43]; p-interaction = .22). Conclusions: In the TWILIGHT trial, the high-risk features correlated more strongly with ischemic than with bleeding risk. Nonetheless, the benefits of ticagrelor compared with ticagrelor plus aspirin were consistent, irrespective of the number of high-risk features. These findings are only applicable to patients who are event-free at 3 months after PCI. Clinical trial registration: The trial was registered with ClinicalTrials.gov, NCT02270242.