On October 19th, 2010 the FDA approved the drug Pradaxa (dabigatran) for prevention of stroke and blood clots in people with abnormal heart rhythm (atrial fibrillation). As compared to warfarin, Pradaxa does not require laboratory monitoring. In one study, people who took Pradaxa had fewer strokes than those who took warfarin. However, Pradaxa is still capable of causing serious bleeding, as is experienced with warfarin, although Pradaxa is less likely to cause intracranial hemorrhage but more gastrointestinal bleeding. Common side-effects seen with Pradaxa are gastrointestinal symptoms which are occur in about 1/3 of users, which includes dyspepsia (generalized stomach discomfort), stomach pain, nausea, heartburn, and bloating. Pradaxa will be available in 75 and 150mg capsules. Pradaxa has been used in Europe and Canada since 2008.
Of interest is that the RE-LY Trial compared various dosing regimens of Pradaxa to warfarin and the 150mg twice daily regimen was superior to warfarin, but also caused the same amount or rate of bleeding as warfarin. The 110mg twice daily regimen showed less bleeding than warfarin but was equally effective yet not superior to warfarin. All-cause mortality was the same in each group, Pradaxa vs. warfarin, and there was a higher rate of heart attacks in the Pradxaxa group (0.74% vs. 0.53%). So is this drug really superior and more advantageous to warfarin? One must also consider Pradaxa costs about ten times more than warfarin, even when we include the cost of routine monitoring as required with warfarin. We’ll need to dig further to see if there are data for the use of this drug in the older adult population such as the old-old adult over 80 (Note: In those >75y/o there was a higher rate of bleeding as compared to warfarin). We will also need more information on drug interactions, a big concern and area of risk with warfarin. For now, if you are well managed on warfarin with stable INRs and no evidence of bleeding, there is no reason to change to Pradaxa. The FDA link is below with the official press release.