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.

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.

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.

Treatment with AboBoNT-A significantly reduced pain in CD vs placebo at 4 weeks post-injection, with benefits persisting for at least 12 weeks. Pain relief was maintained over time with multiple injection cycles.