Reports of deaths and serious bleeding linked to the blood thinner, Pradaxa, continue to mount. According to a new report from the Institute for Safe Medicine Practices (ISMP), the U.S. Food & Drug Administration received 3,781 adverse event reports associated with Pradaxa in 2011, more than were associated with any other drug the agency monitors.
Pradaxa also led in reports of deaths (541), hemorrhage (2,367), kidney failure (291) and stroke (644), according to ISMP’s most recent QuarterWatch report. Pradaxa was also a suspect in 15 reports of liver injury made to the FDA.
Pradaxa was introduced in October 2010, and has become popular due to perceptions that it is it is easier to use than decades-old blood thinner warfarin. Pradaxa does not require frequent laboratory tests to adjust the dose—as does warfarin—and it has fewer drug interactions. However, while warfarin bleeding can be stopped with the administration of vitamin K, there is no readily available antidote for Pradaxa bleeding.
According to the QuarterWatch report, Pradaxa was s approved in one primary dose of 150 mg, which may b leading to excessive doses in the oldest patients, especially those with declining kidney function. As of January 2012, a new manufacturer recommendation now says physicians should “assess renal function during therapy as clinically indicated.” However, the ISMP said it was not clear whether this will lead to safer use, and it remains to be seen if Pradaxa can be managed safely without individualizing the dose.
The FDA launched a review of Pradaxa in December over reports of bleeding-related side effects, while regulators in Europe and Japan have also directed Boehringer Ingelheim to strengthen warnings for the Pradaxa. Most recently, European regulators asked Boehringer Ingelheim, the manufacturer of the Pradaxa, to update the drug’s label with additional information regarding its bleeding side effects. According to the European Medicines Agency (EMA), the new guidance will include more specific information on when Pradaxa must not be used, as well as advice on managing patients and reversing the anticoagulant effect if Pradaxa bleeding occurs.