IncobotulinimtoxinA (Xeomin) for the treatment of adductor laryngeal dystonia: A prospective, open-label clinical trial

Abstract

ObjectivesDemonstrate an understanding of incobotulinumtoxinA efficacy in the treatment of adductor spasmodic dysphonia (SD). Understand that incobotulinumtoxinA can successfully be used as an alternative to onabotulinumtoxinA and for secondary non-responders. MethodsWe conducted a prospective open-label trial from 2016 until 2019 regarding the use of incobotulinimtoxinA for the treatment of adductor spasmodic dysphonia. Exclusion criteria included pregnant/nursing women, botulinum toxin for other indications, known allergy, neuromuscular or systemic diseases, use of aminoglycoside antibiotics, substance abuse, litigation regarding prior therapy, or other confounding conditions. Sixty-four injection sessions with completed with sixteen patients who were enrolled in the study and underwent EMG-guided incobotulinumtoxinA injections to the thyroarytenoid (TA) muscle using a hollow monopolar Teflon-coated needle via a trans-cricothyroid membrane approach. Dosages to each TA muscle were recorded and patients completed a Voice Handicap Index-10 (VHI-10), a validated worksheet regarding their perceived percent of normal function (PNF) following treatment, and a side effect profile. Outcomes were analyzed using the paired t-test. ResultsFor primary transitioners to incobotulinimtoxinA, VHI-10 scores and best percent normal function did not significantly change. For non-responders, VHI-10 decreased from 32.5 on Botox to 19.5 on incobotulinimtoxinA and best PNF increased from 37.6 to 90 %, which was statistically significant. Transient side effects included breathiness. ConclusionsOur study demonstrates that incobotulinimtoxinA may be used successfully for adductor SD either as first line treatment or in secondary non-responders to onabotulinumtoxinA.