Category: Dystonia: Clinical Trials and Therapy
Objective: The aim of this meta-analysis of pivotal studies was to evaluate the efficacy of abobotulinumtoxinA (AboBoNT-A) in reducing pain in patients with cervical dystonia (CD).
Background: Pain is a prominent, disabling feature of CD impacting on quality of life, and is one of the most common reasons for a CD patient to present for treatment with botulinum toxin A (BoNT-A) injections.
Method: We present meta-analyses of patient-level data from four randomized, placebo-controlled studies (Truong et al 2005 & 2010, NCT01261611, NCT01753310) of AboBoNT-A 500U and three associated open-label extension studies. All studies assessed pain using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) pain subscale. The difference between AboBoNT-A and placebo was assessed with an ANCOVA with treatment as fixed effect, baseline values as covariates and subject as random effect.
Results: In the randomized controlled studies, baseline TWSTRS pain scores were 10.5 ±4.0 in the AboBoNT-A group (n=340) and 10.8 ±4.3 in the placebo group (n=203). Treatment with AboBoNT-A significantly reduced Week 4 pain scores by (mean ±SE) -3.2 ±0.2 points in the AboBoNT-A group vs -1.0 ±0.3 points in the placebo group; the treatment difference of -2.2 ±0.4 points vs placebo was statistically significant (p<0.0001). Statistical significance versus placebo was maintained at Week 12 (treatment difference of -1.3 ±0.4 points vs placebo; p=0.0006). In the open-label studies, reductions in Week 4 and Week 12 pain scores were maintained with repeat treatment with AboBoNT-A ensuring relatively consistent symptom control for patients across multiple cycles [Figure].
Conclusion: Treatment with AboBoNT-A significantly reduced pain in CD vs placebo, 4 weeks post-injection and benefits persisted for at least 12 weeks. Pain relief was maintained over time with multiple injection cycles.
To cite this abstract in AMA style:
R. Rosales, L. Cuffe, B. Regnault, R. Trosch. Pain in cervical dystonia: A meta-analysis of outcomes following treatment with abobotulinumtoxinA in randomized, controlled clinical studies [abstract]. Mov Disord. 2021; 36 (suppl 1). https://www.mdsabstracts.org/abstract/pain-in-cervical-dystonia-a-meta-analysis-of-outcomes-following-treatment-with-abobotulinumtoxina-in-randomized-controlled-clinical-studies/. Accessed September 7, 2024.« Back to MDS Virtual Congress 2021
MDS Abstracts - https://www.mdsabstracts.org/abstract/pain-in-cervical-dystonia-a-meta-analysis-of-outcomes-following-treatment-with-abobotulinumtoxina-in-randomized-controlled-clinical-studies/