The study objective was to investigate the safety and efficacy of incobotulinumtoxinA (Xeomin) during repeat dose treatment of glabellar frown lines. 801 subjects with moderate to severe glabellar frown lines at maximum frown who completed participation in one of the studies in this program, i.e., MRZ 60201-0520/1, MRZ 60201-0527/1, MRZ 60201-0724/1, or MRZ 60201-0741/1 were eligible to participate in this repeat-dose study.