FDA’s approval of Bristol-Myers Squibb Co.'s metastatic melanoma immunotherapy Yervoy (ipilimumab) was granted only after looking outside the BLA for assurance that the biologic’s effect was robust and validated. Faced with an application for a second-line indication and a single study showing a survival benefit, but with only modest effects on secondary endpoints, the agency insisted on preliminary overall survival data from an ongoing first-line study to assure itself that approval was warranted.The...