Session Information
Date: Thursday, June 8, 2017
Session Title: Clinical Trials and Therapy in Movement Disorders
Session Time: 1:15pm-2:45pm
Location: Exhibit Hall C
Objective: To determine the efficacy and safety of a 500 U/2 mL dilution of aboBoNT-A as compared to placebo in patients with cervical dystonia (CD).
Background: CD is characterized by involuntary cervical muscle contractions leading to sustained and painful head and neck postures. AbobotulinumtoxinA (aboBoNT-A) is an acetylcholine release inhibitor and a neuromuscular blocking agent indicated for the treatment of adults with CD. US prescribing information for aboBoNT-A previously indicated only a dilution of 500 U/1 mL for the treatment of CD. The indication for a 2 mL dilution would support flexible dosing and give clinicians more freedom in their treatment approach towards their patients.
Methods: We conducted a 12-week, phase 3b multicenter, randomized, double-blind, placebo-controlled trial (NCT01753310). In this study, adult patients with a primary diagnosis of cervical dystonia were randomized (2:1) to receive either aboBoNT-A or placebo. Botulinum neurotoxin (BoNT) naïve patients in the aboBoNT-A group received 500 U/2 mL in ≥2 affected neck muscles. AboBoNT-A patients who had previously received BoNT treatment (non-naïve) received 250 – 500 U/2 mL (2.5:1 aboBoNT-A: previous onabotulinumtoxinA dose) into muscles injected during prior treatments. The primary endpoint was change from baseline to Week 4 in the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) total score.
Results: AA total of 134 (aboBoNT-A, n=89; placebo, n=45) patients were randomized (intent-to-treat population). Of these, 129 patients (aboBoNT-A, n=84; placebo, n=45) completed the Week 4 primary endpoint evaluation (modified intent-to-treat population). When compared to placebo, aboBoNT-A patients experienced significantly greater changes from baseline in TWSTRS total score at Week 4 (-2.5 vs -10.8, P<0.001; based upon the modified intent to treat population). Adverse events (AEs) occurred in 41% and 22% of aboBoNT-A and placebo patients, respectively. Dysphagia was reported in 9% of treated patients. Other AEs observed in treated patients were muscle weakness, neck pain, and headache.
Conclusions: This study indicates a 2 mL dilution of aboBoNT-A was significantly more effective when compared to placebo. No unexpected AEs were observed relative to previous studies that used the 1 mL dilution volume.
Previously Presented at Toxins, 18-21 Jan 2017
To cite this abstract in AMA style:
M. Lew, D. Snyder. Efficacy and Safety of a 2 mL Dilution of AbobotulinumtoxinA Compared With Placebo in Adult Patients With Cervical Dystonia [abstract]. Mov Disord. 2017; 32 (suppl 2). https://www.mdsabstracts.org/abstract/efficacy-and-safety-of-a-2-ml-dilution-of-abobotulinumtoxina-compared-with-placebo-in-adult-patients-with-cervical-dystonia/. Accessed May 24, 2025.« Back to 2017 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/efficacy-and-safety-of-a-2-ml-dilution-of-abobotulinumtoxina-compared-with-placebo-in-adult-patients-with-cervical-dystonia/