A New Blood Thinner Receives FDA Approval for Venous Blockage – Venous Thromboembolism

On 23 June 2017, the United States Food and Drug Administration FDA approved betrixaban (trade name Bevyxxa) for adults hospitalized with acute illness who are at risk of thromboembolic complications (blood vessel blockage) because of moderately or severely restricted mobility and have other venous thromboembolism risk factors.

Betrixaban is an oral factor Xa inhibitor. FDA approved it under priority review, a method used for drugs that may provide important treatment advances or address conditions without adequate treatment.

What Is Venous Thromboembolism (VTE)?

Venous blockage, medically called venous thromboembolism, is a leading cause of death and disability worldwide. Patients hospitalized for serious conditions such as heart failure, stroke, cancer, infection and lung disease are vulnerable to it. In cancer patients in particular, vascular blockage is common both because of the disease itself and as a treatment adverse effect. This condition may not always produce clinically detectable signs and symptoms, and unfortunately even its first symptoms can be fatal. Preventive treatment (prophylaxis) is therefore important.

Approval is based on a randomized, double-blind, multinational study in patients hospitalized with acute illness and risk factors for venous blockage, comparing treatments to prevent the condition: long-term betrixaban (35 to 42 days) versus short-term enoxaparin (6 to 14 days), using data from the phase 3 APEX clinical trial.

In the study, 7513 patients received preventive, or prophylactic, anticoagulant treatment. Patients in the betrixaban arm received an oral loading dose of 160 mg on the first day, followed for 35 to 42 days by daily betrixaban 80 mg, and for 6 to 14 days a once-daily placebo injection. Patients in the enoxaparin arm received, for 6 to 14 days, once-daily subcutaneous enoxaparin 40 mg, and for 35 to 42 days a once-daily oral placebo.

Drug efficacy was measured using a composite outcome including asymptomatic (causing no complaints) or symptomatic (causing complaints and signs) deep vein thrombosis, nonfatal pulmonary embolism or death associated with venous blockage.

In conclusion, fewer adverse events were reported in betrixaban patients (% 4.4) than in enoxaparin patients (% 6).

The most common betrixaban adverse effects (≥% 5) were reported to involve bleeding. Overall, at least one adverse reaction occurred in %54 of betrixaban patients and %52 of enoxaparin patients. Serious adverse event frequency was similar in the betrixaban (%18) and enoxaparin (% 17) arms.

Bleeding leading to treatment discontinuation, relative to all bleeding, occurred in % 2.4 of the betrixaban arm and %1.2 of the enoxaparin arm. Major bleeding rates were % 0.67 and % 0.57, respectively. The recommended betrixaban regimen starts on the first day with a loading dose of 160 mg, followed at the same time daily for 35-42 days by 80 mg taken with food.

Oral administration makes betrixaban convenient for patients. We will share developments if it also receives approval in our country.