An Open-Label, Sequential Dose-Escalation, Safety, and Tolerability Study of Rimabotulinumtoxinb in Subjects With Cervical Dystonia

ABSTRACT

Objectives: Evaluate the safety and efficacy of a sequential dose escalation of rimabotulinumtoxinB (BoNT-B) in cervical dystonia (CD) subjects. Methods: This multicenter, open-label, within-subject, sequential dose-escalation study (BoNT-B dosed at 10,000, 12,500, and 15,000 Units) evaluated subjects over each phase of treatment at preinjection and at periodic intervals postinjection. Adverse events, vital signs, and laboratory results were recorded. Efficacy measures included the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and three visual analog scales (VASs). Results: 119 out of 145 CD subjects received all three doses in sequence. Dry mouth and dysphagia were the most common adverse events, and both decreased in frequency by the final injection, despite the increasing doses of the escalation. TWSTRS-Total and subscale scores demonstrated significant improvements following all doses at the week 2, 4, 8, and 12 assessments, with the exception of disability and pain at week 12 with the lowest dose. All VAS scores demonstrated similar improvements following all doses. The mean number of weeks in each phase of the study was 12.1 weeks (10,000 Units), 12.9 weeks (12,500 Units), and 13.9 weeks (15,000 Units). Conclusion: BoNT-B was well tolerated and efficacious at 10,000, 12,500, and 15,000 Units in this within-subject, sequential dose-escalation study in CD subjects.

KEYWORDS: :

• botulinum toxin
• type B
• cervical dystonia
• Myobloc
• NeuroBloc
• rimabotulinumtoxinB