Pradaxa Side Effects Prompt Kidney Test Warning in EuropeOct 28, 2011 | Parker Waichman LLP
Regulators in Europe have reached an agreement with the maker of Pradaxa to add new warnings to the drug advising that certain patients undergo kidney testing before beginning the anti-clotting medication.
Because Pradaxa is excreted through the kidneys, impaired kidney function could lead to abnormally high levels of the drug in circulation, leading to excessive risk of bleeding. Boehringer Ingelheim agreed that renal function testing was necessary prior to the commencement of Pradaxa therapy under an agreement with the European Union's top drug regulator, the European Medicines Agency. The company will also notify doctors that patients older than 75 and those with renal impairment should undergo kidney checks every year.
"While on treatment, renal function should be assessed in clinical situations where a decline in renal function is suspected (e.g. hypovolemia, dehydration, and with certain co-medications)," a statement from the EMA said. "In patients older than 75 or with renal impairment, renal function should be assessed at least yearly whilst on treatment. Given Pradaxa is mainly excreted renally, the treatment should not be prescribed to patients with severe renal impairment (creatinine clearance less than 30 ml/min)."
This isn't the first time Pradaxa has caused safety concerns. 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. As of a month ago, CARM had been alerted to four deaths; however, it said none were caused by Pradaxa.
In Japan, Boehringer Ingelheim was ordered 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. According to Reuters, five of those patients died.
According to a report issued by the Institute for Safe Medication Practices (ISMP), since its October 2010, Pradaxa has been named in more U.S. Food & Drug Administration (FDA) Adverse Event Reports than more than 98% of the medications the group monitors.
The ISMP report also found Pradaxa is already being used off-label. It was approved to prevent stroke in people with atrial fibrillation, but only a third of prescriptions written for it have been for such patients. It seems doctors are adopting Pradaxa as a more general use blood thinner.