The US Food and Drug Administration (FDA) has granted Fast Track designation for Anthos Therapeutics’ fully human monoclonal antibody abelacimab to investigate it for preventing stroke and systemic embolism in atrial fibrillation (AF) patients.

The new dual-acting, once-monthly antibody abelacimab has been designed for inducing hemostasis-sparing anticoagulation through inhibition of Factor XI.

Targeting Factor XI’s active domain, the antibody shows dual inhibitory activity against Factor XI as well as its activated form, Factor XIa, with high selectivity and affinity.

The latest move marks the second Fast Track designation granted by FDA to abelacimab.

In July, the antibody received the Fast Track designation to treat cancer-associated thrombosis (CAT).

It has also become the first Factor XI inhibitor to commence subject enrolment in Phase III trials earlier this year.

Anthos Therapeutics chief medical officer Dan Bloomfield said: “Real-world evidence has shown that adherence to current therapies is less than ideal for many patients, including those with atrial fibrillation and cancer-associated thrombosisi. This non-adherence may be associated with an increased risk of stroke.

“With one in four people dying from thromboembolic events globally, the need to do better is urgent.

“As a company, we remain highly committed to working closely with the FDA to bring once monthly abelacimab to patients in need.”

The company stated that abelacimab gave intravenously (IV) suppressed Factor XI within one hour of the treatment and maintained near maximal inhibition for up to 30 days in a PK/PD study.

Additionally, a single IV abelacimab dose following a knee surgery showed an 80% reduction in venous thromboembolism rate compared to enoxaparin in a Phase II study.