OnabotulinumToxinA Reduces Pharmacological Burden in Chronic Migraine Patients: A Two-Center Prospective Cohort Study. - Montisano, Danilo Antonio; Parisi, Alessandra; Raggi, Alberto; Altamura, Claudia; D'Onofrio, Luigi; Marcosano, Marilena; Fofi, Luisa; Marcassoli, Alessia; Vernieri, Fabrizio; Grazzi, Licia (Toxins, 2026)