Abelacimab effectively prevents postoperative venous thromboembolism: NEJM

There is very limited evidence for the exact role of factor XI in the pathogenesis of postoperative venous thromboembolism. Abelacimab is a monoclonal antibody that binds to factor XI and locks it in the zymogen conformation.

A study was conducted by Verhamme P et. al to investigate the exact role of Abelacimab that inhibits Factor XI in prevention of venous thromboembolism.

The researchers performed an open-labeled, parallel-group trial, wherein they randomly assigned 412 patients who were undergoing total knee arthroplasty to receive one of three regimens of abelacimab:

· 30 mg administered postoperatively in a single intravenous dose

· 75 mg administered postoperatively in a single intravenous dose

· 150 mg administered postoperatively in a single intravenous dose

or to receive 40 mg of enoxaparin administered subcutaneously once daily.

The primary efficacy outcome was venous thromboembolism, detected by compulsory venography of the leg involved in the operation or objective confirmation of symptomatic events.

The principal safety outcome was a composite of major or clinically relevant nonmajor bleeding up to 30 days after surgery.

The results of the study are as follows:

· Venous thromboembolism occurred in 13 of 102 patients (13%) in the 30-mg abelacimab group, 5 of 99 patients (5%) in the 75-mg abelacimab group, and 4 of 98 patients (4%) in the 150-mg abelacimab group, as compared with 22 of 101 patients (22%) in the enoxaparin group.

· The 30-mg abelacimab regimen was noninferior to enoxaparin, and the 75-mg and 150-mg abelacimab regimens were superior to enoxaparin.

· Bleeding occurred in 2%, 2%, and none of the patients in the 30-mg, 75-mg, and 150-mg abelacimab groups, respectively, and in none of the patients in the enoxaparin group.

The researchers concluded that factor XI is crucial for the development of postoperative venous thromboembolism. And with a single intravenous dose of abelacimab Factor XI was inhibited in patients who underwent total knee arthroplasty and it was ultimately effective for the prevention of venous thromboembolism as well as was associated with a low risk of bleeding.

Reference:

A study titled, "Abelacimab for Prevention of Venous Thromboembolism" by Verhamme P et. al published in the new England journal of medicine.

DOI: 10.1056/NEJMoa2105872