Pradaxa Warnings Updated in Canada for Those With Kidney Problems

Canadian health officials have added new label warnings to the blood thinner Pradaxa, known there as Pradax, indicating the risk of bleeding events may be increased among individuals with kidney problems. 

The new Pradaxa warnings were announced by Health Canada on March 16, indicating that all patients should have their renal function assessed before starting Pradaxa, and that doctors should routinely assess any changes in renal function while on the treatment, especially among patients over 75 years old.

Health Canada also indicated that use of Pradaxa was not recommended for individuals with significant rheumatic valvular heart disease, especially mitral stenosis, or patients with prosthetic heart valves, as the safety and efficacy of Pradaxa has not been studied among those individuals.

Pradaxa (dabigatran) is a relatively new blood thinner, which was introduced by Boehringer Ingelheim as a superior alternative to Coumadin (warfarin) for prevention of strokes among individuals with atrial fibrillations.

The new warnings in Canada come as concerns about the risk of serious and potentially fatal bleeding events from Pradaxa increases among the medical community in the United States and several other countries. Since the medication was introduced in the U.S. in October 2010, hundreds of deaths have been reported among Pradaxa users who experienced internal bleeding or hemorrhages that doctors were unable to stop.

Although Pradaxa has been promoted as a superior alternative to Coumadin (warfarin), because it requires less monitoring, the medication lacks a method for doctors to control bleeding problems that do occur.  Among users of the older, cheaper drug Coumadin, bleeding events can be addressed by giving the patient a dose of Vitamin K.

According to a report released by the Institute for Safe Medication Practices in January 2012, more instances of Pradaxa hemorrhages 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 events were reported, compared to 176 cases reported with warfarin/Coumadin, which was second on the list.

Health Canada indicates that the new warnings for Pradaxa are based on post-marketing reports of serious bleeding events among elderly patients given Pradaxa, especially those with severe kidney problems, for whom it is now contraindicated. The level of impairment can be determined by calculating the patient’s creatinine clearance (CrCl). A CrCL of less than 30 mL/min is considered severe kidney impairment.

In December 2011, the FDA announced that it was evaluating post-marketing reports on the Pradaxa bleeding events to determine if there is anything abnormal about the side effects of Pradaxa, and whether the anticoagulant may pose an unreasonable risk for certain consumers.

A number of individuals throughout the United States are now pursuing a Pradaxa lawsuit after experience severe bleeding problems. The lawsuits allege that Boehringer Ingelheim failed to adequately research the side effects of their medication. When it became apparent that the risk of bleeding events were causing a number of serious injuries throughout the United States, the drug maker should have provided stronger warnings or issued a Pradaxa recall, according to many of the complaints filed.