Some heart doctors are raising concerns about a new class of heart drugs that include Pradaxa. Recently, a number of doctors interviewed by Reuters said they were hesitant to prescribe Pradaxa, as well as another blood thinner called Xarelto, because of concerns regarding the risk of stroke, serious bleeding and blood clots, particularly in patients with poor kidney function.
Pradaxa was approved by the U.S. Food & Drug Administration (FDA) in October 2010 to prevent strokes in patients with an irregular heartbeat called atrial fibrillation. Xarelto was approved last November for atrial fibrillation. Both were meant to be alternatives to decades-old warfarin, which requries regular blood monitoring or frequent doctor follow-up. Makers of the drugs also say there was far less evidence in trials of brain bleeding with Pradaxa and Xarelto compared to warfarin.
But Pradaxa or Xarelto do have other issues. Doctors interviewed by Reuters said that patients using either drug should undergo testing ahead of time make sure their kidneys are functioning well. They also said patients should be educated about the drugs’ potential dangers and be seen by doctors periodically, especially after a switch is made from warfarin.
Like any blood thinner, Pradaxa and Xarelto can cause serious internal bleeding. But unlike warfarin, there is no known antidote for either Pradaxa or Xarelto bleeding. According to Reuters report, that has some doctors concerned.
“What really compounds the matter is the lack of a specific antidote to reverse life-threatening bleeding” from the drugs, Dr. Sanjay Kaul, a cardiologist at Cedars-Sinai Medical Center in Los Angeles, told Reuters. Kaul said he’s heard from about a dozen doctors about Pradaxa bleeding, most of which involved cases where the patients’ kidneys weren’t tested prior to starting the drug. Weak kidneys allow Pradaxa to build to unsafe levels in the bloodstream.
“The good news is you now have an alternative to warfarin,” said Dr. Alan Jacobson, director of anti-coagulation services at the Veterans Administration (VA) healthcare system in Loma Linda, California. “The bad news is you can kill a patient as easily with the new drug as you could with the old drug” if it is not handled properly.
As we’ve reportedly previously, a number of concerning cases have been reported involving Pradaxa patients who died from serious internal bleeding following a minor trauma, such as a fall that resulted in a bump to the head. The FDA launched a review of Pradaxa in December over reports of bleeding-related side effects, while regulators in Europe and Japan have directed Boehringer Ingelheim to strengthen warnings for the drug.
Most recently, European regulators asked Boehringer Ingelheim, the manufacturer of the Pradaxa, to update the drug’s label with additional information regarding its bleeding side effects. As we reported, the European Medicines Agency (EMA) wanted the label to include more specific information regarding when Pradaxa must not be used, as well as advice on managing patients and reversing the anticoagulant effect if Pradaxa bleeding occurs. The request followed one the EMA had made in November, when it asked Boehringer Ingelheim to add more information about bleeding to Pradaxa’s label, including a caution that it be prescribed at lower doses to older patients and those with kidney problems.