Pradaxa Side Effects May Have Killed 50 in First Year

The blood thinner Pradaxa has been linked to about 50 deaths in its first year on the market, according to its manufacturer, Boehringer Ingelheim. 

The company announced this week that it is investigating the Pradaxa deaths, but said that the fatalities, mostly caused by bleeding complications, are in the expected range for the drug.

The numbers were released after an inquiry by Japanese officials, whose country has had 14 of those deaths among Pradaxa users.

Japan has called for additional label warnings on the drug, and in Europe doctors have been advised to test patients’ kidney functions to reduce chances of bleeding complications. The drug was approved for use in the U.K. on Tuesday.

Some researchers have recently questioned the validity of the drug’s pre-approval clinical trials, indicating that the drug should have never been approved because the trials were fundamentally flawed.

The drug is meant to be a replacement for warfarin and is supposedly easier to use and requires less monitoring, but warfarin can be quickly counteracted by doses of Vitamin K when a bleeding problem occurs. There is no such quick fix for a bleeding problem with Pradaxa. It is a problem shared by all of the newest generation of blood thinners, which also includes Xarelto, Eliquis and Lixiana.

Pradaxa (dabigatran) was only released in October 2010, but has received more consumer complaints to the FDA’s MedWatch adverse event reporting system than 98.7% of the other drugs on the market.

Some patients and doctors report that the drug sometimes has too much of an effect on clotting, leading to hemorrhages. Other reports indicate that at times it does not have enough of an effect, resulting in pulmonary embolism or deep vein thrombosis.

According to a report by the Institute of Safe Medication Practices (ISMP), the FDA received hundreds of complaints about problems from Pradaxa within weeks of its release. Most of the cases were bleeding problems in elderly users. Overall, the FDA received 307 complaints about Pradaxa side effects in the last quarter of 2010, compared to 202 complaints involving warfarin.