Typically, botulinum toxin injections for blepharospasm or cervical dystonia (CD) are administered at approximately 3-month intervals, reflecting concerns that shorter intervals might increase the risk of adverse events (AEs) and development of neutralizing antibodies. These post-hoc analyses investigated flexible incobotulinumtoxinA (Xeomin®) injection intervals (6-20 weeks) in patients with blepharospasm or CD. Patients received up to 6 injections at intervals ≥ 6 weeks, as determined by physician assessment upon patient request. The blepharospasm study permitted flexible doses (≤ 50 U/eye). The CD study employed fixed dosing using incobotulinumtoxinA 120 U, 240 U, or placebo for the first treatment followed by subsequent randomization to 120 U or 240 U for the extension period. Standard safety assessments were performed. Intervals <12 weeks were employed in 207 of 461 (44.9%) treatment cycles for blepharospasm and in 369 of 821 (44.9%) treatment cycles for CD. The most frequent AEs were eyelid ptosis and dry eyes in patients treated for blepharospasm, and dysphagia and neck pain in patients with CD. AE frequency and severity were similar for intervals <12 weeks and ≥ 12 weeks in both studies. In conclusion, repeated incobotulinumtoxinA injections employing flexible intervals (6-20 weeks) per patients' needs were well tolerated. No additional safety concerns were observed with <12-week intervals compared with ≥ 12-week intervals.
Keywords: Blepharospasm; Botulinum toxin; Cervical dystonia; IncobotulinumtoxinA; Patient satisfaction; Xeomin®.
Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.