Botulinumtoxin Typ B: Möglichkeiten und Grenzen der klinischen Anwendungen

Recently, NeuroBloc((R)) was registered in the European Union as a new botulinum toxin drug for the treatment of cervical dystonia. NeuroBloc((R)) is a ready to use solution of botulinum toxin type B (BT-B) blocking the acetylcholin transport protein VAMP in the nerve terminal. This differentiates it from conventional preparations using botulinum toxin type A (BT-A). For treatment of cervical dystonia the efficacy of NeuroBloc((R)) is similar that of BT-A preparations. However, peripheral systemic anticholinergic side effects, not seen with BT-A, are frequent. Hence, the relationship between motor and autonomic effects of NeuroBloc((R)) is clearly different from that of BT-A preparations. NeuroBloc((R)) can be successfully used in patients with cervical dystonia and antibody-induced BT-A therapy failure, Whether formation of BT-B antibodies occurs after prolonged NeuroBloc((R)) application in those patients is not known yet. NeuroBloc((R)) can also be used successfully in de novo patients with cervical dystonia and in patients with cervical dystonia undergoing successful BT-A-therapy. Crossover studies will have to provide a conversion factor between BT-A and Neurobloc((R)) dosages. Therapeutic use for these indications can only be recommended after establishing that the therapeutic advantages of NeuroBloc((R)) over BT-A preparations outweigh its increased side effect frequency.