TOPIC: Benefits of Switching Dual Antiplatelet Therapy in Patients with ACS

Newer P2Y12 blockers are the front-line treatment and dual antiplatelet therapy is indicated for 1 year after acute coronary syndrome (ACS).

Both prasugrel and ticagrelor offer more ischemic benefit than clopidogrel during the initial phase; however, bleeding complications could increase in the long term. The objective of this study was to assess the safety and efficacy of switching dual antiplatelet therapy (DAPT) to a newer, “more powerful” combination including aspirin plus prasugrel or ticagrelor for the first month, followed by aspirin plus clopidogrel the next 11 months after ACS.

Patients enrolled presented ACS and had undergone angioplasty revascularization without ischemic or bleeding events within the first month after the ACS event.

They were randomized to switch DAPT (aspirin plus prasugrel or ticagrelor for 1 month, followed by aspirin plus clopidogrel the next 11 months) or continuation of their DAPT regimen (aspirin plus prasugrel or ticagrelor for 12 months). The primary endpoint was a composite of death, urgent revascularization, stroke, and ≥2 bleeding (as defined by the Bleeding Academic Research Consortium [BARC] classification) at 1 year. The secondary endpoint was similar but included all BARC or TIMI (Thrombolysis in Myocardial Infarction) bleeding categories.

A total 646 patients with ACS who had undergone angioplasty were randomized. The primary endpoint was 52% lower among patients who switched DAPT after 1 month than among those who maintained the “powerful” regimen for 1 year (13.4% for switch DAPT at 1 month vs. 26.3% for unchanged DAPT throughout the year; hazard ratio [HR]: 0.48; 95% CI: 0.34-0.68; p < 0,01).

No significant differences were reported on ischaemic endpoints, which were similar for both groups (9.3% vs. 11.5%, respectively; HR: 0.80; 95% CI: 0.50-1.29; p = 0.36), but, as expected, there was a 70% reduction in the rate of BARC ≥2 bleeding (4.0% vs. 14.9% at 1 year, respectively; HR: 0.30; 95% CI: 0.18-0.50; p < 0,01).

Conclusion

In patients admitted with acute coronary syndrome who required angioplasty and did not experience adverse events within 1 month, a switched DAPT from a powerful aspirin plus prasugrel or ticagrelor regimen to aspirin plus clopidogrel was superior to a whole year on aspirin plus prasugrel or ticagrelor, due to the significant reduction in bleeding events without an increase in ischemic events.

Original title: Benefit of Switched Dual Antiplatelet Therapy After Acute Coronary Syndrome: The TOPIC (Timing Of Platelet Inhibition after acute Coronary Syndrome) Randomized Study.

Presenter: Thomas Cuisset.

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