Abstract
Purpose:
To compare the effective dose and treatment interval for onabotulinumtoxinA (Botox) and incobotulinumtoxinA (Xeomin) among patients with blepharospasm (BEB) and hemifacial spasm (HFS).
Methods:
Retrospective review of BEB and HFS patients treated with onabotulinumtoxinA and incobotulinumtoxinA. From 2003 to 2011, patients were treated with onabotulinumtoxinA. IncobotulinumtoxinA was used from 2011 onward. Patients were re-injected when symptoms worsened. Patients were required to receive at least two injections with onabotulinumtoxinA and at least three with incobotulinumtoxinA (at least two treatment intervals for each toxin) over a minimum treatment duration of 90 weeks. Effective dose was determined as the minimum dose which controlled symptoms. We compared onabotulinumtoxinA and incobotulinumtoxinA with regard to average effective dose and treatment interval across all patients. We also performed intra-patient analyses and compared effective dose and average treatment intervals (onabotulinumtoxinA v. incobotulinumtoxinA) for each patient.
Results:
Twenty-six patients were included: 15 with BEB, nine with HFS, and two with secondary blepharospasm. From 2003 to 2011, we administered 323 treatments with onabotulinumtoxinA. From 2011 onward, we administered 150 treatments with incobotulinumtoxinA. There was no significant difference between the two toxins with regard to average effective dose (33.1 units for onabotulinumtoxinA v. 34.5 units for incobotulinumtoxinA, p=0.6864). Average treatment interval was also not significantly different (17.4 weeks for onabotulinumtoxinA v. 16.7 weeks for incobotulinumtoxinA, p=0.2749). In individual patient analyses, 18 patients (69%) required no change in dose when switching from onabotulinumtoxinA to incobotulinumtoxinA. Of the remaining eight patients, five had an increase in dose with incobotulinumtoxinA (average increase of 9.6 units more); three patients required a lower dose of incobotulinumtoxinA (4 units less on average). 23 of the 26 patients (96%) showed no significant difference with regard to average interval between onabotulinumtoxinA injections compared to their average interval with incobotulinumtoxinA.
Conclusions:
OnabotulinumtoxinA and incobotulinumtoxinA appear to demonstrate similar dosing parameters and have similar durations of effect in patients with BEB and HFS.
Keywords: 526 eyelid •
561 injection