Pradaxa is a prescription drug blood-thinning medicine used to reduce the risk of stroke and blood clots in people with atrial fibrillation (AF) not caused by a heart valve problem.
The problem with Pradaxa risks is that the FDA is evaluating post-marketing reports of serious bleeding in patients taking Pradaxa. Bleeding that may lead to serious or fatal results is a well-known complication of blood thinners. The Pradaxa drug label contains a warning about significant and sometimes fatal bleeding.
Pradaxa is eliminated by the kidneys, so kidney function should be reviewed prior to treatment to determine the appropriate dose. Kidney function should be reassessed during treatment and the dose should be adjusted following recommendations in the label.
For patients with non-valvular AF, the main alternative to Pradaxa is warfarin (Coumadin). Because warfarin has been marketed for more than 50 years and is well-known to cause bleeding, patients and healthcare professionals are not likely to report bleeding in association with warfarin.
FDA is working with Boehringer Ingelheim, the Pradaxa maker, to analyze the post-market reports for evidence of inappropriate dosing, use of interacting drugs, or other clinical factors that could lead to bleeding.
Pradaxa clinical trial issues
More than 18,000 patients participated in a clinical trial comparing Pradaxa and Coumadin. Major bleeding events occurred at similar rates with both drugs.
In the clinical trial, patients taking Pradaxa had fewer strokes than those who took Coumadin.On October 19, 2010, the FDA approved Pradaxa 75 mg and 150 mg capsules for the prevention of stroke and blood clots in patients with abnormal heart rhythm or AF. Pradaxa is made by Boehringer Ingelheim Pharmaceuticals Inc. of Ridgefield, Conn.
As with other approved blood thinner drugs, bleeding, including life-threatening and fatal bleeding, was among the most common adverse reactions reported by patients treated with Pradaxa. Gastrointestinal symptoms, including stomach pain, nausea, heartburn, and bloating were also reported.
A report of about 50 cases of fatal bleeding worldwide associated with the drug surfaced in November 2011. On December 7, 2011, slightly more than one year later of approving Pradaxa— the FDA announced that despite post marketing reports of severe bleeding – patients should continue to take Pradaxa.
However, during the clinical trial, 110 mg and 150 mg capsules were tested not 75 mg. How can one dose be tested in a Pradaxa clinical trial and another dose released into the pharmaceutical marketplace without testing? Is that ethical?
In an article published by the New England Journal of Medicine, AF patients taking 150 mg twice a day of Pradaxa had lower rates of hemorrhagic stroke and ischemic stroke than patients taking Coumadin.