European regulators have urged doctors to prescribe Pradaxa with caution, following roughly 260 reports of fatal bleeding among patients taking the blood thinner. Despite the Pradaxa bleeding deaths, the European Medicines Agency (EMA) said Friday that the efficacy of Pradaxa as demonstrated in clinical trials remained unchanged.
According to a report from TheHeart.org, there have been 260 reports of fatal bleeding among Pradaxa patients worldwide, including 21 in Europe. The events occurred between March 2008 and October 31, 2011, according to a spokesperson from Boehringer Ingelheim, the maker of Pradaxa. The spokesperson maintained that the number was in line with expectations for bleeding events based on the pivotal RE-LY trial, which was used to garner approval for Pradaxa in the U.S. and Europe.
â€œThe number of reports of bleedings in patients treated with Pradaxa has to be seen in the context of the rapidly increasing use of Pradaxa worldwide as a result of approval of a new indication (prevention of stroke and systemic embolism in adult patients with non-valvular atrial fibrillation) in several regions of the world and also the increased awareness about the drug, a factor that is known to lead to higher than usual reporting of side effects,” the EMA said in a statement issued yesterday.
The EMA said its Committee for Medicinal Products for Human Use (CHMP) is of the opinion that changes to the use of Pradaxa it recommended last month “adequately manage the risk of bleeding.” The EMA was referring to an advisory that cautioned European doctors to subject Pradaxa patients older than 75, as well as those with renal impairment, to annual kidney checks. Pradaxa is excreted through the kidneys, thus impaired kidney function could lead to abnormally high levels of the drug in circulation, leading to excessive risk of bleeding.
Pradaxa is used to prevent strokes in people with atrial fibrillation, and is one of a number of new anti-blood-clotting pills expected to replace warfarin. Unlike warfarin, Pradaxa is not associated with dangerous interactions with some foods. However, excessive bleeding from warfarin can be treated with vitamin K, while there is no antidote for this side effect when it occurs in Pradaxa patients. Pradaxa has been available in Europe since 2008, but was only approved by the U.S. Food & Drug Administration (FDA) in October 2010.
In August, regulators in Japan â€“ where the drug is sold as Prazaxa â€“ told Boehringer Ingelheim to issue a warning for Pradaxa and potentially fatal bleeding after 81 of the almost 64,000 mainly elderly patients taking it there suffered heavy bleeding. In New Zealand, 122 cases of side effects in Pradaxa patients have been reported to the Centre for Adverse Reactions Monitoring (CARM), of which two out of five involved bleeding.
In October, the Institute for Safe Medication Practices (ISMP) reported that since its U.S. approval last year, Pradaxa has been named in more U.S. Food & Drug Administration (FDA) adverse event reports than over 98% of the medications the group monitors. Pradaxa side effect reports outpaced most other drugs, including warfarin, with the majority involving serious bleeding or blood clots in the elderly, the ISMP said.