Xeomin® in the treatment of cervical dystonia

BACKGROUND AND PURPOSE: Botulinum toxin type A (BoNT/A) is a highly effective and well-tolerated treatment for focal dystonias. The BoNT/A in Botox and Dysport is part of a high-molecular-weight complex that contains hemagglutinins and other non-toxic proteins, whilst Xeomin is a highly purified BoNT/A free of such complexing proteins. In the largest controlled study of BoNT/A published to date (Neurology 2005; 64: 1949), it was demonstrated that Xeomin is non-inferior to Botox and has 1:1 efficacy in the treatment of cervical dystonia. A possible limitation of continued BoNT/A treatment is antibody development. Based on its physiochemical properties and toxicological evidence, Xeomin is expected to have a reduced incidence of non-responders after long-term treatment compared with other marketed BoNT/A products. METHODS AND RESULTS: In our ongoing open-label study, 100 patients suffering from cervical dystonia are continuously treated with Xeomin; 50 patients were treated de novo, the remaining patients had been previously treated with Botox, Dysport or NeuroBloc/Myobloc. All patients showed negative results in antibody testing at the beginning of Xeomin treatment. During continuous treatment with Xeomin up to 2 years, patients continued to respond well to Xeomin treatment. CONCLUSION: The treatment was well tolerated and no patient has developed neutralizing antibodies as measured using the sensitive mouse hemidiaphragma assay within these first 2 years.