The botulinum toxins in the treatment of cervical dystonia.

The use of botulinum toxin to treat cervical dystonia (CD) has dramatically improved the quality of life of patients with this disabling, often painful disease. Two forms of toxins, botulinum toxin type A (BTX-A) and botulinum toxin type B (BTX-B), have each been studied in large multicenter trials in subjects with CD. A study of BTX-A demonstrated improvement of 5.15 to 10.65 degrees in head position using the Cervical Dystonia Severity Scale (CDSS) in those treated with BTX-A (trade name BOTOX) compared with placebo. A study in patients who continued to respond to BTX-A and a similarly designed study in patients who were resistant to BTX-A demonstrated statistical improvement in the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) in those treated with BTX-B (evaluated as NeuroBloc) compared with placebo. The potential availability of both forms of toxin will allow physicians to offer further treatment options to patients with CD.