Boehringer Ingelheim’s Pradaxa (dabigatran etexilate) has been known to increase the risk of bleeding, but recent reports indicate that this occurrence may be more frequent, and more severe than previously thought. The blood thinning drug was only approved within the past few years and has experienced a number of setbacks since its recent introduction. Reports of over 260 deaths last year led regulators to update safety regulations and launch investigations concerning Pradaxa. Most recently, a group of hematologists in New Zealand urge for better, more substantial information regarding Pradaxa among prescribers after citing serious bleeding risks associated with the drug.
Pradaxa is an anticoagulant meant to prevent the occurrence of blood clots and stroke, particularly in patients who experience an abnormal heart rhythm (atrial fibrillation). It works by directly inhibiting thrombin, a necessary clotting factor. Approved by the U.S. Food and Drug Administration (FDA) in 2010, the drug was expected to replace Coumadin (warfarin), an older anticoagulant that also happens to serve as a pesticide against rodents.
Problems with Pradaxa began last year, when cases of severe gastrointestinal and cerebral bleeding were reported. Safety concerns arose as early as February, when The Institute for Safe Medication Practices (ISMP), a U.S. non-profit organization, issued an alert after a chronic kidney patient experienced severe hemorrhaging while taking Pradaxa. Several months later, Japanese health regulators asked Boehringer to update its safety warning after reported cases of GI bleeding. Then, the EMA’s Committee for Medicinal Products for Human Use (CHMP) updated the drug’s safety warning to include contraindications in patients who had renal dysfunction and severe bleeding. Healthcare professionals were also informed to take extra precaution for elderly patients.
A major blow to the drug’s safety profile was the report of approximately 260 worldwide deaths in connection to Pradaxa. The events caused the FDA to launch a safety investigation of the drug in December. Weeks after the FDA announced the beginnings of its review, the ISMP released reports showing that over 500 cases of Pradaxa-linked bleeding were reported to the FDA during the first quarter of 2011. These hemorrhaging cases led to death, hospitalization and other severe consequences.
Now, more disparaging information mounts against Pradaxa. In a letter to the New England Journal of Medicine, a group of New Zealand hematologists push for greater measures and better education regarding the relatively new drug. The results of a two month review revealed 78 cases of bleeding associated with Pradaxa. Out of these cases, a dozen were a major hemorrhage with one case suspected of causing a patient’s death. The review was conducted by Paul Harper, MD, of Palmerston North Hospital in Palmerston North, New Zealand, and his colleagues. Harper and his team found that the bleeding cases were heavily affected by impaired renal health, the age of the patient and mistakes made by the physician prescribing the drug. Another major concern was the fact that there is no antidote for the induced bleeding, a point that was also made by Japanese regulators back in August. Dr. Harper emphasized that “The serious consequences of the lack of an effective reversal agent should not be underestimated,” cites Medpage
Today. He went on to say that “Prolonged bleeding increased morbidity and possibly contributed to the death of one patient.” The latest findings emphasize greater knowledge, and precaution, among Pradaxa prescribers.