FDA puts Boehringer's Pradaxa under review

Boehringer Ingelheim's new blood thinner Pradaxa is now in the FDA's crosshairs. The U.S. regulator is reviewing reports of serious bleeding in patients using Pradaxa, the first drug approved in a generation of alternatives to the anticoagulant therapy warfarin. The FDA said patients should continue using the drug for now, and Pradaxa offers "an important health benefit when used as directed."

The FDA's safety review comes on the heels of a warning from European regulators issued in November. The European Medicines Agency cited 256 cases of fatal bleeding, saying doctors should be cautious when prescribing Pradaxa. Patients suspected of poor kidney function should be tested before they use the drug, Boehringer advised at EMA's behest, because too much of the drug could build up in a patient's bloodstream if not properly cleared by the kidneys.

The FDA says it's looking at the reports of serious bleeding to determine whether cases are cropping up more frequently than would be expected, PharmaTimes reports. Comparing bleeding events in Pradaxa patients with those in warfarin patients is difficult, however, because warfarin is known to cause bleeding--and bleeding in warfarin patients can be quickly reversed with an antidote. So, warfarin-related bleeding is less likely to be reported, the FDA said.

As PharmaTimes reports, Boehringer said 1.1 million Pradaxa prescriptions were dispensed from October 2010 to August, and 371,000 patients received the drug from U.S. pharmacies. "The clinical effectiveness and favorable safety profile of Pradaxa is positive and remains unchanged," the company said.

- see the FDA statement
- get more from Reuters
- read the PharmaTimes piece