IncobotulinumtoxinA (Xeomin) is a botulinum toxin type A preparation free of complexing proteins, i.e. free of proteins other than the active toxin. Injected into the muscle, IncobotulinumtoxinA (Xeomin) causes local weakening. Botulinum toxin type A is widely used for aesthetic treatment of facial lines. This study investigated the efficacy and safety of IncobotulinumtoxinA (Xeomin) in the treatment of glabellar frown lines compared to placebo. The study consisted of a Main Period and an Open-Label Extension [OLEX] Period of 120 days each.