If approved by the regulatory authorities, AMG 334 is expected to prove tough competition to other migraine drugs such as Novartis's (NVS) Lopressor, Pfizer's (PFE) Corgard, and GlaxoSmithKline's (GSK) Imigran. (For more on Amgen's migraine research programs, please refer to " Amgen's Research Pipeline in Neuroscience and Inflammation .")