Factor XI inhibitors and atrial fibrillation: imminent breakthrough or false start?

Area of Science:

• Cardiology
• Pharmacology
• Thrombosis Research

Background:

• Atrial fibrillation (AF) increases thrombo-embolic event risk, necessitating anticoagulant therapy.
• Current anticoagulants (VKAs, DOACs) carry bleeding risks.
• Factor XI (FXI) inhibitors offer a potential alternative with reduced bleeding risk and maintained efficacy.

Purpose of the Study:

• To evaluate the emerging role of FXI inhibitors in managing AF-related thrombo-embolic events.
• To assess the safety and efficacy profile of novel FXI inhibitors like abelacimab, asundexian, and milvexian.

Main Methods:

• Review of ongoing and completed clinical trials investigating FXI inhibitors in AF patients.
• Analysis of preliminary safety and efficacy data from trials such as AZALEA-TIMI 71 and OCEANIC-AF.

Main Results:

• Abelacimab demonstrated reduced major bleeding versus rivaroxaban in a prematurely terminated Phase 2 trial.
• Asundexian was discontinued due to inferiority compared to apixaban in a Phase 3 study.
• Preliminary efficacy data for FXI inhibitors in AF is not yet convincing.

Conclusions:

• FXI inhibitors represent a potential therapeutic advancement for AF, offering a potentially safer anticoagulant option.
• Further robust clinical trial data from studies like LILAC-TIMI 76 and LIBREXIA-AF are essential.
• The definitive clinical role of FXI inhibitors in AF treatment requires additional evidence to confirm both safety and efficacy.