RimabotulinumtoxinB Effects on Pain Associated with Cervical Dystonia: Results of Placebo and Comparator-Controlled Studies

Response rate (RR) and mean improvement (MI) in the pain subscale of the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS-PS) from two placebo-controlled studies and one comparator-controlled study were evaluated to examine the effect of rimabotulinumtoxinB (BoNT-B) on cervical dystonia (CD) pain. Subjects receiving either of two doses of BoNT-B in the AN072-301 trial had an RR of 66% and 58% compared with 23% for placebo (p < .05). Subjects receiving BoNT-B in the AN072-302 trial had an RR of 49% compared with 19% for placebo (p < .05). Subjects receiving BoNT-B in the AN072-402 comparator-controlled trial had a significantly higher RR than those treated with BoNT-A (59% vs. 36%; p < .05). Additionally, subjects treated with BoNT-B in these placebo-controlled trials had significantly larger MIs than those treated with placebo (4.3 and 3.7 vs. 0.5 for AN072-301 and 3.6 vs. 0.1 for AN072-302; p < .05). Subjects treated with BoNT-B in the comparator-controlled trial demonstrated a numerically larger MI than those treated with BoNT-A (2.6 vs. 1.8; p = .1651). These results support the consideration of BoNT-B as an effective first-line botulinum toxin treatment for patients with CD who list pain as a primary complaint.