The RE-LY study that led to the FDA’s approval of dabigatran compared two different regimens of the drug — 110 or 150 mg twice daily — against warfarin. Both were noninferior to warfarin, so why didn’t the FDA approve both, giving clinicians and patients a choice?

Writing in the New England Journal of Medicine, FDA scientists explain that the 110-mg dose, while superior to both warfarin and the 150-mg dose in reducing risk for major bleeding, carried a greater risk for stroke. The higher bleeding risk with the 150-mg dose, in the FDA’s judgment, was acceptable, given “that the irreversible effects of strokes and systemic emboli have greater clinical significance than nonfatal bleeding.”

In addition, patients who suffered a bleeding event while on the higher dose were unlikely to suffer another, even when they continued taking the medication at the higher dose.

Source: NEJM perspective