title: A double blind, randomised, parallel group study to investigate the dose equivalence of Dysport and Botox in the treatment of cervical dystonia.
abstract: OBJECTIVE
  This study was designed to establish whether a ratio of three units of Dysport is equivalent to one unit of Botox for the treatment of cervical dystonia.
  
  
  METHODS
  Patients with predominantly rotational cervical dystonia, and a minimum of four previous Botox treatments, were randomised to receive either the clinically indicated dose of Botox or three times that dose in Dysport units. Study botulinum toxin was administered in a double blind fashion, to one or more clinically indicated muscles, at one or more sites per muscle. Patients returned for assessment two, four, eight, and 12 weeks after treatment.
  
  
  RESULTS
  A total of 73 patients (Dysport, 38; Botox, 35) were entered. The Dysport group received a mean (SD) dose of 477 (131) (range 240-720) Dysport units, and the Botox group received a mean (SD) dose of 152 (45) (range 70-240) Botox units. The mean (SEM) post-treatment Tsui scores for the Dysport group (4.8 (0.3)) and the Botox group (5.0 (0.3)) were not statistically different (p=0.66). The study had 91% power to detect a clinically significant difference of two points. Both groups showed substantial improvement in Tsui score by week 2 (mean (SD); Dysport, 46 (28)%; Botox, 37 (28)%), with a peak effect at week 4 (mean (SD); Dysport, 49 (29)%; Botox, 44 (28)%). A similar response profile was seen for other assessments of efficacy. The duration of effect, assessed by time to retreatment, was also similar (mean (SD); Dysport, 83.9 (13.6) days; Botox, 80.7 (14.4) days; p=0.85). During the study 22 of 38 (58%) Dysport patients reported 39 adverse events, and 24 of 35 (69%) Botox patients reported 56 adverse events (p=0.35). A global assessment of efficacy and safety considered that 29 of 38 (76%) Dysport patients and 23 of 35 (66%) Botox patients were treatment successes (p=0.32).
  
  
  CONCLUSIONS
  Patients with predominantly rotational cervical dystonia treated with the clinically indicated dose of Botox or three times that dose in Dysport units show similar improvements and do not have significantly different safety profiles.
authors.affiliation: Department of Neurology, Karolinska Hospital, Stockholm, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Odergren
authors.forename: H
authors.initials: H
authors.lastname: Hjaltason
authors.forename: S
authors.initials: S
authors.lastname: Kaakkola
authors.forename: G
authors.initials: G
authors.lastname: Solders
authors.forename: J
authors.initials: J
authors.lastname: Hanko
authors.forename: C
authors.initials: C
authors.lastname: Fehling
authors.forename: R J
authors.initials: RJ
authors.lastname: Marttila
authors.forename: H
authors.initials: H
authors.lastname: Lundh
authors.forename: S
authors.initials: S
authors.lastname: Gedin
authors.forename: I
authors.initials: I
authors.lastname: Westergren
authors.forename: A
authors.initials: A
authors.lastname: Richardson
authors.forename: C
authors.initials: C
authors.lastname: Dott
authors.forename: H
authors.initials: H
authors.lastname: Cohen
mesh_terms: D000328:Adult; D000368:Aged; D019274:Botulinum Toxins, Type A / Q000737:chemistry* / Q000493:pharmacokinetics / Q000600:supply & distribution / Q000627:therapeutic use*; D004311:Double-Blind Method; D004421:Dystonia / Q000150:complications / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D010147:Pain Measurement; D012720:Severity of Illness Index; D013810:Therapeutic Equivalency; D014103:Torticollis / Q000150:complications / Q000188:drug therapy*
chemical_list: D019274:Botulinum Toxins, Type A