Efficacy and safety of incobotulinumtoxinA (NT 201, XEOMIN®, botulinum neurotoxin type A, without accessory proteins) in patients with cervical dystonia.

OBJECTIVE

IncobotulinumtoxinA differs from available formulations in that it does not have accessory proteins. IncobotulinumtoxinA has previously shown non-inferiority to onabotulinumtoxinA for the treatment of CD with a 1:1 dosing regimen. The objective of this study was to compare the safety and efficacy of incobotulinumtoxinA (120 U, 240 U; Merz Pharmaceuticals) to placebo in subjects with cervical dystonia (CD).

METHODS

This was a prospective, double-blind, randomized, placebo-controlled, multicenter clinical trial in botulinum toxin-treated or toxin-naïve CD patients. The primary outcome measure was change from baseline to Week 4 on the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) Total score. Adverse events (AEs) also were evaluated.

RESULTS

Participants (N=233) were mostly women (66%), a mean of 52.8 years old, who had CD for a mean of 51.9 months. Of those, 39% were toxin-naïve. IncobotulinumtoxinA significantly improved TWSTRS-Total scores from baseline to Week 4 compared to placebo (placebo=-2.2; 120 U=-9.9, and 240 U=-10.9; 240 U vs. placebo p<0.001 and 120 U vs. placebo p<0.001). This effect persisted through to the end of the study. The most frequently reported AEs in the incobotulinumtoxinA groups were dysphagia, neck pain, and muscular weakness which were generally mild.

INTERPRETATION

IncobotulinumtoxinA (at doses of 120 U or 240 U) is a safe and effective treatment for CD in previously-treated as well as toxin-naïve subjects.