Category: Dystonia: Clinical Trials and Therapy
Objective: The efficacy of incobotulinumtoxinA, a botulinum neurotoxin type A free from complexing proteins, was investigated in a randomized, placebo-controlled, prospective, Phase III study in toxin-naïve subjects with benign essential blepharospasm (BEB) (NCT01896895). We report a sub-analysis of the flexible re-injection interval that was employed in this study to mirror clinical practice.
Background: Blepharospasm is a focal dystonia characterized by involuntary eye closure due to excessive contractions of the eyelid muscles. Botulinum neurotoxin type A (BoNT-A) injections are an approved treatment for BEB.
Method: Treatment-naïve subjects (18–80 years) with bilateral BEB and Jankovic Rating Scale severity subscore ≥2 were enrolled in Greece, Malaysia, and Sri Lanka. In the
double-blind main period, subjects were randomized (1:1:1) to single intramuscular injections of incobotulinumtoxinA 25 U (12.5 U/eye), 50 U (25 U/eye), or placebo. During a subsequent observation period of 6–20 weeks, the patient’s subjective assessment of onset and waning of effect was recorded.
Results: Overall, 61 subjects were randomized (mean 55.0 years; 59.0% female) and included in this analysis. Data are reported as median (first quartile, third quartile). The treatment interval was longer with incobotulinumtoxinA 50 U (20 [6.1, 20.6] weeks) and 25 U (11 [6.1, 19.6] weeks) compared with placebo (6 [0, 19.2] weeks). Time to onset was shorter with incobotulinumtoxinA 50 U (5.0 [3.0, 10.0] days) and 25 U (7.0 [4.0, 22.0] days) compared with placebo (14.0 [4.0, 42.5] days). Time to waning was similar between treatment groups (incobotulinumtoxinA 50 U: 12.0 [8.0, 17.9] weeks; 25 U: 11.0 [3.0, 18.0] weeks; placebo: 11.5 [5.0, 18.2] weeks).
Conclusion: IncobotulinumtoxinA had a sustained duration of effect in toxin-naïve subjects with BEB, with a median treatment interval of 20 weeks and time to waning of 12 weeks
with 50 U.
To cite this abstract in AMA style:
F. Pagan, A. Dekundy, M. Althaus, A. Scheschonka, J. Jankovic, D. Mitsikostas. Duration of Effect of IncobotulinumtoxinA for the Treatment of Blepharospasm in Botulinum Toxin-naïve Subjects: Results from a Phase III Study [abstract]. Mov Disord. 2020; 35 (suppl 1). https://www.mdsabstracts.org/abstract/duration-of-effect-of-incobotulinumtoxina-for-the-treatment-of-blepharospasm-in-botulinum-toxin-naive-subjects-results-from-a-phase-iii-study/. Accessed June 15, 2025.« Back to MDS Virtual Congress 2020
MDS Abstracts - https://www.mdsabstracts.org/abstract/duration-of-effect-of-incobotulinumtoxina-for-the-treatment-of-blepharospasm-in-botulinum-toxin-naive-subjects-results-from-a-phase-iii-study/