Efficacy and Safety of PrabotulinumtoxinA for the Treatment of Glabellar Lines in Adult Subjects: Results From 2 Identical Phase III Studies

PrabotulinumtoxinA is a 900-kDa botulinum toxin Type A produced by Clostridium botulinum. OBJECTIVE: To investigate the efficacy and safety of prabotulinumtoxinA for the treatment of glabellar lines. MATERIALS AND METHODS: Adult subjects (n = 330 in EV-001; n = 324 in EV-002) with moderate to severe glabellar lines at maximum frown on the 4-point Glabellar Line Scale (GLS; 0 = no lines, 1 = mild, 2 = moderate, and 3 = severe) were enrolled in 1 of 2 identical 150-day, double-blind, placebo-controlled, single-dose, Phase III studies. Subjects were randomized 3:1 to receive 20-U prabotulinumtoxinA or placebo. The primary efficacy end point was the proportion of responders on Day 30 where the investigator and subject independently agreed that a ≥2-point improvement had occurred on the GLS at maximum frown from Day 0. Adverse events (AEs) were evaluated throughout the study. RESULTS: Responder rates in the prabotulinumtoxinA and placebo groups were 67.5% and 1.2% in EV-001 and 70.4% and 1.3% in EV-002; absolute differences between groups were 66.3% and 69.1% in EV-001 and EV-002, respectively (both p < .001). No serious AE in either study was assessed as study drug related. CONCLUSION: In these studies, a single dose of 20-U prabotulinumtoxinA was safe and effective for the treatment of glabellar lines.