Safety of NOAC instead of aspirin in ACS patients

Clinically significant bleeding with low-dose rivaroxaban versus aspirin, in addition to P2Y12 inhibition, in acute coronary syndromes (GEMINI-ACS-1): a double-blind, multicentre, randomised trial

Presented at ACC.17 by Magnus E Ohman

News - Mar. 18, 2017

Background

Dual antiplatelet therapy (DAPT) has been the cornerstone of the treatment of ACS and is recommended by guidelines for the post-ACS therapy. However, despite optimal DAPT, approximately 10% of ACS patients present with recurrent ischaemic events. The addition of certain anticoagulants to DAPT led to further reduction of ischaemic events in this setting, with a 3- to 4-fold increase in major bleedings. Studies including patients with an indication for full-dose oral anticoagulation undergoing PCI, suggested, however, that withholding aspirin was not associated with an increase in ischaemic events but with a lower risk of major bleedings.

In this study, the safety of a low dose of the oral anticoagulant rivaroxaban, a direct factor Xa inhibitor, was compared with aspirin, on top of a P2Y12 inhibitor, in 3037 post-ACS patients.

Main results

The median duration of treatment with blinded study drug was 291 days (IQR: 239–354) and the median duration of follow-up was 326 days (IQR: 284–383).
Premature treatment discontinuation occurred in 11% of patients treated with rivaroxaban vs. 13% of patients treated with aspirin. Early discontinuation of P2Y12 inhibitor therapy was 4.4% in the overall population.
49% of patients presented with STEMI, 40% with NSTEMI, and 11% with unstable angina. 87% of patients were treated with PCI for their index ACS before randomisation.
The primary endpoint of TIMI non-CABG clinically significant bleeding occurred in 5% of patients on rivaroxaban and 5% of patients on aspirin (HR: 1.09; 95% CI: 0.80–1.50; P=0.5840). The most common type of bleeding was TIMI bleeding requiring medical attention (4% in the rivaroxaban group and 4% in the aspirin group), with a low frequency of severe or major bleeding events using TIMI bleeding definitions.
Using the ISTH definition for major bleeding, a higher rate of bleeding was noted with rivaroxaban compared with aspirin (2% vs. 1%; P=0.0420), but there were no differences using GUSTO or BARC bleeding definitions, regardless of severity.
The frequency of the composite ischaemic endpoint of CV death, MI, stroke, or definite stent thrombosis was 5% in both groups (HR: 1.06; 95% CI: 0.77–1.46; P=0.7316).

Conclusion

A safety study of rivaroxaban versus aspirin, on top of P2Y12 therapy in ACS patients, showed that this dual antithrombotic regimen had a similar risk of clinically significant bleeding. These findings suggest that substituting aspirin with low-dose rivaroxaban is a safe therapeutic option in this setting.

Disclosures

Our coverage of ACC.17 is based on the information provided during the congress.

The accompanying article was published today in The Lancet