Daiichi Sankyo's atrial fibrillation-treating edoxaban posted promising results in Phase III, matching the stroke-prevention prowess of warfarin with a better safety profile, but the drug may struggle to carve out market share in a cluttered space. Daiichi plans to file for approval early next year, and, with the FDA's blessing, edoxaban would compete with Johnson & Johnson ($JNJ) and Bayer's Xarelto, Bristol-Myers Squibb ($BMY) and Pfizer's ($PFE) Eliquis, and Boehringer Ingelheim's Pradaxa, not to mention the still-popular and ever-cheap warfarin. Article