AbobotulinumtoxinA for the Treatment of Moderate-to-Severe Glabellar Lines: A Randomized, Dose-Escalating, Double-Blind Study

Objective: To evaluate the efficacy and safety of AbobotulinumtoxinA (ABO) dose escalation in the correction of moderate-to-severe glabellar lines. Design: Phase 2, 36-week, multicenter, randomized, dose-ranging, double-blind, placebo-controlled study. Methods: Adults with moderate-to-severe glabellar lines received a single ABO treatment, dosed at 50, 75, 100, or 125 U, or placebo. Primary endpoint was week 4 composite ≥2-grade responder rate among those achieving a severity score of 0 (none) or 1 (mild) at maximum frown, evaluated using concurrent investigator and subject assessments. Secondary endpoints included ≥1-grade severity improvement, duration of effect, and reporting of treatment-emergent adverse events (TEAEs). Results: Overall, 399 subjects were included (88.2% were female). Week 4 composite ≥2-grade ABO responder rate was 80.0% (50 U), 88.8% (75 U), 90.0% (100 U) and 95.1% (125 U), versus 2.6% with placebo (P<0.001). Responder rate (≥1-grade) ranged between 53% (50 U) and 69% (125 U) at week 24 and between 18% (50 U) and 31% (125 U) at week 36. Median time (weeks) to return to baseline severity/worse, among those scoring 0 (none) or 1 (mild), was 32.3 (50 U), 34.3 (75 U), 36.0 (100 U) and 36.6 (125 U), versus 23.7 (placebo). ABO-related TEAEs were reported in 4% of subjects (80% were mild). No seroconversion to ABO neutralizing antibodies was seen. Conclusion: A single ABO treatment provided rapid and effective improvements in glabellar line severity at all doses. Higher doses tended to demonstrate elevated response rates and longer duration of effect. All ABO doses were well-tolerated with low TEAE incidence. J Drugs Dermatol. 2021;20(9):980-987. doi:10.36849/JDD.6263