The study ARPH-CL-03 is a multicenter, randomized, double-blind, three parallel group design with moderate to severe migraine patients to assess the ability of daily administration of AST-726 at one of two doses to reduce the number of headache days in a 4 week period more than in patients that receive a placebo. AST-726 and the placebo will be self-administered by intranasal spray daily for 12 weeks. Among other efficacy and safety assessments, patients will have be asked to collect information on a daily migraine diary.