BOTULINUM TOXIN TYPE-B - A DOUBLE-BLIND, PLACEBO-CONTROLLED, SAFETY AND EFFICACY STUDY IN CERVICAL DYSTONIA

We enrolled and treated 122 patients with idiopathic cervical dystonia in a double-blind, placebo-controlled safety and efficacy study of bo tulinum toxin type B (BotB). Both A-responsive and A-resistant patient s were enrolled. Patients received intramuscular injections of either BotB (2,500 U, 5,000 U, or 10,000 U) or placebo. The primary outcome m easure of efficacy was the Toronto Western Spasmodic Torticollis Ratin g Scale (TWSTRS)-Total score at 4 weeks following study drug administr ation. Secondary measures of efficacy were TWSTRS-Severity, -Disabilit y, and -Pain subscale scores, and Analog Pain Assessment, Investigator Global Assessment, Patient Global Assessment, and Sickness Impact Pro file scores. Duration of effect was estimated with an intent-to-treat analysis of responders. Safety measures included clinical parameters, laboratory tests, and adverse events. The primary and most of the seco ndary analyses indicated a statistically significant treatment effect and a dose response. BotB is safe, well tolerated, and efficacious in the treatment of cervical dystonia at the doses tested.