Efficacy and safety of incobotulinumtoxinA (NT 201, Xeomin) in the treatment of blepharospasm-a randomized trial

Abstract

IncobotulinumtoxinA (NT 201, Xeomin) is a highly purified botulinum neurotoxin type A formulation, free from complexing proteins. A randomized, placebo-controlled, double-blind trial of efficacy and safety compared incobotulinumtoxinA (up to 50 U per eye) to placebo administered in a single treatment session to patients with blepharospasm. All patients had documented satisfactory response to 2 previous treatments with botulinum neurotoxin type A other than incobotulinumtoxinA and had Jankovic Rating Scale severity subscores ≥ 2. Patients (n = 109) were randomized in a 2:1 ratio to incobotulinumtoxinA or placebo and followed up to 20 weeks; 94% completed the study. A significant difference was observed in the primary efficacy variable (change in Jankovic Rating Scale severity subscore rated by an independent rater 6 weeks following treatment), favoring incobotulinumtoxinA by 1.0 point (95% CI [0.5-1.4]; P < .001). Functional impairment, as measured by the Blepharospasm Disability Index, improved by 0.5 points (95% CI [0.2-0.7]; P = .002) compared with placebo. There was a strong correlation between the 2 scale scores. In addition, all secondary outcome measures favored incobotulinumtoxinA. Patients rated the mean therapeutic effect of incobotulinumtoxinA significantly better than placebo (P < .001). Adverse events were reported in 70.3% of incobotulinumtoxinA patients and 58.8% of placebo patients. Eyelid ptosis (18.9% vs 5.9%), dry eye (18.9% vs 11.8%), and dry mouth (14.9% vs 2.9%) occurred most frequently. Tolerability was rated good/very good by 91.9% of incobotulinumtoxinA versus in 85.2% of placebo patients. In conclusion, incobotulinumtoxinA was well tolerated and was associated with statistically significant and clinically relevant reductions in blepharospasm severity and functional impairment.