Xeomin® was proven effective in two randomized, double-blind, multicenter, placebo-controlled clinical trials of 547 healthy, adult patients. The average age of patients in the study was 46 years. Patients received 20 Units of Xeomin® and were classified as responders if they had a 2-grade improvement on a 4-point scale as assessed by the physician and patient. Using these criteria, treatment success was higher with Xeomin® than placebo on Day 30 in both studies (60% and 48% vs. 0% for placebo in both studies). Based on these trials, Xeomin® received FDA approval for use in glabellar lines in 2011.