January 3rd, 2014
FDA Plans New Safety Assessment of Dabigatran (Pradaxa)
Larry Husten, PHD
Since the approval of dabigatran (Pradaxa, Boehringer Ingelheim) in Europe in 2008 and in the U.S. in 2010 there have been persistent and lingering concerns about the drug’s safety. Now the FDA plans to perform a large new assessment of the drug compared to warfarin.
On December 30 the FDA posted a request for public comment on a proposed protocol of the study, which it describes as “a one-time assessment of selected safety outcomes in adults with atrial fibrillation who are new users of dabigatran or warfarin.” The study will “assess systematically the rates of bleeding and thromboembolic outcomes associated with the use of dabigatran and warfarin for patients with atrial fibrillation using data from the FDA Mini-Sentinel Distributed Database (MSDD).”
The Mini-Sentinel project is a part of the FDA’s Sentinel active surveillance system. Mini-Sentinel, according to the FDA, uses pre-existing electronic healthcare data from multiple sources. The Mini-Sentinel database, the FDA notes, “is not so ‘mini’,” as it includes 17 data partners and uses data from nearly 100 million patients.
At this point there is no plan to assess the safety of the new oral anticoagulants that received approval after dabigatran — rivaroxaban (Xarelto, Johnson & Johnson) and Eliquis (Pfizer and BristolMysers Squibb).
A knowledgeable source said that the major purpose of the study will be to identify groups of patients who are at high risk for major bleeding events with dabigatran. Somewhat paradoxically, this might help bolster the drug, as it will then also identify groups more likely to benefit from treatment. On the other hand, the fact that similar studies are not being undertaken with the other new oral anticoagulants may well reinforce concerns about dabigatran.