Xeomin in the treatment of cervical dystonia

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.

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.

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.