Significant isn't meaningful

Despite meeting the primary endpoints in two Phase III trials, last week Frova frovatriptan was deemed not approvable to prevent menstrual migraine. In yet another sign that FDA is moving the goalposts on product approvals, Vernalis plc and partner Endo Pharmaceuticals Holdings Inc. said the agency questioned whether the benefit was "clinically meaningful."

The trial protocols did not prespecify the magnitude of a treatment difference that might be deemed "clinically meaningful," according to Stephen Silberstein, principal investigator on the first pivotal study and director of the headache center in the department of neurology at Thomas Jefferson University Hospital...