CHICAGO--(BUSINESS WIRE)--Clinical results from a Phase II study presented for the first time at the American Headache Society (AHS) annual meeting showed that MK-0974, an investigational oral calcitonin gene-related peptide (CGRP) receptor antagonist, significantly improved migraine pain relief two hours after dosing compared to placebo, and the relief was sustained through 24 hours. MK-0974 was generally well tolerated in the study. Responses specific to other measures, such as migraine-associated symptoms, functional disability and use of additional rescue medications also were reported. MK-0974 is Merck’s investigational medicine in Phase III clinical development for the acute treatment of migraine in adults and, if approved, may be the first in a new class of migraine treatments since the approval of the first triptan drug in 1991.