First Major Trial Win for Contemporary DOACs in Lower-Risk Afib

A recent clinical trial, SINGLE-AF, has demonstrated that direct oral anticoagulants (DOACs) may offer a clinical benefit for lower-risk patients with atrial fibrillation (Afib) who have one thromboembolic risk factor. The study, led by Boyoung Joung of Yonsei University College of Medicine in Seoul, South Korea, was presented at the European Society of Cardiology meeting in Munich, Germany.

Compared to no anticoagulation, DOAC therapy reduced the risk of composite cardiovascular events at 24 months by 31% (0.5% vs 1.5%). However, the number of primary endpoint events was very low, with a stroke incidence of just 0.6% without anticoagulation and 0.15% with DOACs, potentially leading to an overestimation of the true benefit. Other endpoints such as systemic embolism and major bleeding were also similar between the two groups.

DOACs are currently the first-line therapy for patients with Afib who have two or more risk factors for stroke, but are limited in lower-risk patients due to their increased risk of gastrointestinal bleeding. While the SINGLE-AF trial does not provide a rigorous enough basis for changing U.S. guidelines, it does suggest that DOAC therapy may be encouraged for intermediate-risk patients with Afib and a single risk factor for stroke.

Further research into new anticoagulants, such as asundexian and factor XI inhibitors, may offer safer options for the intermediate-risk Afib population. As treatment options continue to evolve, there is potential for emerging therapies in the future.