AT THE AHA SCIENTIFIC SESSIONS
ANAHEIM, CALIF. (FRONTLINE MEDICAL NEWS) – The benefit of dabigatran dual therapy versus warfarin triple therapy after percutaneous coronary intervention in patients with atrial fibrillation was consistent whether patients had drug-eluting or bare-metal stents, concomitant treatment with ticagrelor or clopidogrel, or acute coronary syndrome or stable disease as the indication for PCI, according to a subgroup analysis of the RE-DUAL PCI trial.
The trial, presented at the American Heart Association scientific sessions,randomized 2,725 patients to triple therapy with warfarin plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and aspirin – the triple therapy group – or dabigatran 110 mg or 150 mg twice daily plus clopidogrel or ticagrelor – the dual therapy groups ( N Engl J Med. 2017 Oct 19;377:1513-24 ).
After a mean follow-up 14 months, the incidence of the major or clinically relevant nonmajor bleeding was 15.4% in the 110-mg dual-therapy group (hazard ratio, 0.52; 95% CI, 0.42-0.63; P less than .001) and 20.2% in the 150-mg dual-therapy group (HR, 0.72; 95% CI, 0.58-0.88; P less than .001), versus about 26% with triple-therapy.
The incidence of the composite efficacy endpoint – death, unplanned revascularization, myocardial infarction, stroke, or systemic embolism – was 13.7% in the two dual-therapy groups versus 13.4% with triple-therapy (HR, 1.04; 95% CI, 0.84-1.29; P = .005).
The investigators found consistent results when they analyzed their prespecified subgroups.
Acute coronary syndrome (ACS) was the indication for PCI in about half the patients; the rest had stable coronary artery disease. The two groups were well balanced except ACS patients were more likely to be new to oral anticoagulation. Results were consistent with the main trial in terms of bleeding. There was a trend for more embolic events in ACS patients on dabigatran 110 mg, but it was not significant, said investigator Jonas Oldgren, MD of Uppsala (Sweden) University.
Drug-eluting stents were placed in 83% of patients; the rest had bare metal stents (BMS). The groups were well-balanced, except BMS patients were again more likely to be new to oral anticoagulation. Bleeding, thromboembolic events, and mortality were consistent with the main results regardless of the stent type, Most of the subjects were on clopidogrel, with just 12% on ticagrelor in both the dabigatran and warfarin groups. Ticagrelor patients were more likely to have ACS as their PCI indication and be new to oral anticoagulation. Ticagrelor patients were also more clinically complex, with a higher bleeding risk. Even so, they had relative bleeding risk reduction and efficacy results with dabigatran that were consistent with the overall finding, Dr. Oldgren said.
Patients were eligible for RE-DUAL PCI (Evaluation of Dual Therapy with Dabigatran vs. Triple Therapy with Warfarin in Patients with AF That Undergo a PCI with Stenting) if they had nonvalvular atrial fibrillation and a successful PCI within 120 hours. Those with bioprosthetic or mechanical heart valves, severe renal insufficiency, or other major comorbidities were excluded.
The trial was funded by Boehringer Ingelheim, the maker of dabigatran. Several investigators were employees. Dr. Oldgren is an adviser to Boehringer Ingelheim. Other authors reported financial ties to the company as well.