FDA approves Praxbind, the first reversal agent for the anticoagulant Pradaxa

The U.S. Food and Drug Administration today granted accelerated approval to Praxbind (idarucizumab) for use in patients who are taking the anticoagulant Pradaxa (dabigatran) during emergency situations when there is a need to reverse Pradaxa’s blood-thinning effects.

The FDA approved Pradaxa in 2010 to prevent stroke and systemic blood clots in patients with atrial fibrillation, as well as for the treatment and prevention of deep venous thrombosis and pulmonary embolism. Praxbind is the first reversal agent approved specifically for Pradaxa and works by binding to the drug compound to neutralize its effect. Praxbind solution is for intravenous injection.

The safety and effectiveness of Praxbind were studied in three trials involving a total of 283 healthy volunteers taking Pradaxa (i.e., people who did not require an anticoagulant). In the healthy volunteers who were given Praxbind, there was an immediate reduction in the amount of Pradaxa in participants’ blood (measured as unbound dabigatran plasma concentration) that lasted for a period of at least 24 hours. In this study, the most common side effect from use of Praxbind was headache.

Another trial included 123 patients taking Pradaxa who received Praxbind due to uncontrolled bleeding or because they required emergency surgery. In this ongoing trial, based on laboratory testing, the anticoagulant effect of Pradaxa was fully reversed in 89 percent of patients within four hours of receiving Praxbind. In this patient trial, the most common side effects were low potassium (hypokalemia), confusion, constipation, fever and pneumonia.

Reversing the effect of Pradaxa exposes patients to the risk of blood clots and stroke from their underlying disease (such as atrial fibrillation). The Praxbind labeling recommends patients resume their anticoagulant therapy as soon as medically appropriate, as determined by their health care provider.

Praxbind is approved under the FDA’s accelerated approval program, which allows the agency to approve drugs for serious conditions that fill an unmet medical need based on an effect on a surrogate or an intermediate clinical endpoint that is reasonably likely to predict a clinical benefit to patients. The program is designed to provide patients with earlier access to promising new drugs, but the company will be required to submit additional clinical information after approval to confirm the drug’s clinical benefit.

Praxbind and Pradaxa are both marketed by Boehringer Ingelheim of Ridgefield, Connecticut.