Increased Pradaxa Bleeding Risk When Compared to Warfarin: Study

A new study suggests that side effects of Pradaxa, a relatively new blood thinner, may increase the risk of bleeding events even more than warfarin, the drug it was designed to replace. 

In a study published in the Journal of the American College of Cardiology, Kansas researchers tested the use of Pradaxa during radiofrequency ablation of atrial fibrillation and discovered more than double the number of bleeding problems with Pradaxa, when compared to those seen when warfarin was used.

The research comes as Pradaxa (dabigatran) is under increased scrutiny from federal health regulators amid a large number of post-marketing reports involving severe bleeding events and deaths reported with Pradaxa during the first year the blood thinner was available.

Pradaxa was introduced by Boehringer Ingelheim in October 2010, as an alternative to Coumadin (warfarin) for prevention of strokes among individuals with atrial fibrillation. The drug was heavily marketed as superior to warfarin, because it is easier to use and requires less monitoring. However, when serious bleeding events do occur, warfarin can be quickly counteracted by doses of Vitamin K, while there is no such quick fix for bleeding with Pradaxa.

Researchers from the University of Kansas Hospital and Medical Center conducted a multicenter, observational study to see if Pradaxa could be used as a blood thinner during atrial fibrillation ablation. The study involved 290 patients, half of whom were giving Pradaxa and the other half were given warfarin.

Pradaxa users experienced a much higher rate of bleeding problems and increased rates of thromboembolic complications, such as strokes and mini-strokes. The researchers discovered that, overall, 16% of Pradaxa users experienced bleeding complications and strokes, compared to only 6% of those given warfarin.

According to a report released by the Institute for Safe Medication Practices in January 2012, more instances of hemorrhages with Pradaxa were reported to the FDA’s Adverse Event Reporting System during the first quarter of 2011 than were reported in association with any other drug monitored by the group. At least 505 instances involving Pradaxa bleeding were reported, compared to 176 cases reported with warfarin, which was second on the list.

A number of individuals throughout the United States who have experienced severe bleeding problems are considering a potential Pradaxa lawsuit against Boehringer Ingelheim for failing to adequately research their medication or warn about the risk of internal bleeding.