title: A randomized, double-masked, crossover comparison of the efficacy and safety of botulinum toxin type A produced from the original bulk toxin source and current bulk toxin source for the treatment of cervical dystonia.
abstract: In 1997, the US FDA approved a new bulk toxin source (now referred to as current) for the manufacture of botulinum toxin type A (BTX-A). The current BTX-A preparation has a lower neurotoxin complex protein load than the original BTX-A preparation, which may reduce antigenic potential. The present double-masked, multicenter study compared the efficacy and safety of BTX-A (BOTOX) produced from both original and current bulk toxin sources for the treatment of cervical dystonia. Patients (N = 133) were injected with BTX-A produced from original and current bulk toxin sources using a crossover design. Adverse events were assessed at each visit. Efficacy was assessed at 2 and 6 weeks post-injection using the severity and pain-disability subscales of the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). Mean BTX-A doses were comparable (original: 155 U, current: 156 U). Both BTX-A preparations produced similar, statistically significant reductions in TWSTRS severity and pain-disability scores at weeks 2 and 6 post-injection. The original and current BTX-A preparations showed no significant differences in adverse events, including both treatment-related (34%, 31%) and treatment-unrelated (27%, 32%), respectively. BTX-A produced from the original and current bulk toxin sources showed comparable efficacy and safety in the treatment of cervical dystonia; both significantly reduced dystonia severity and pain.
authors.affiliation: Neurologische Universitatsklinik, Würzburg, Germany. naumann@mail.uni-wuerzburg.de
authors.forename: M
authors.initials: M
authors.lastname: Naumann
authors.forename: A
authors.initials: A
authors.lastname: Yakovleff
authors.forename: F
authors.initials: F
authors.lastname: Durif
mesh_terms: D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000009:adverse effects* / Q000138:chemical synthesis*; D018592:Cross-Over Studies; D004185:Disability Evaluation; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004361:Drug Tolerance / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000138:chemical synthesis*; D010146:Pain / Q000188:drug therapy / Q000503:physiopathology; D010147:Pain Measurement; D020127:Recovery of Function / Q000187:drug effects / Q000502:physiology; D014103:Torticollis / Q000188:drug therapy* / Q000503:physiopathology; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A