[Initial experiences with clinical use of botulinum toxin type B]

Recently, botulinum toxin type B (BT-B) was introduced for treatment of cervical dystonia (CD). We wish to report on experience with BT-B derived from registration studies and from our own preliminary clinical experience. Botulinum toxin type B can be used successfully in CD patients with antibody-induced failure of botulinum toxin type A therapy (antibody patients). In our own 15 antibody patients, 11835 +/- 2,039 mouse units of BT-B (NeuroBloc) reduced the Toronto Western spasmodic torticollis rating scale (TWSTRS) score from 20.5 +/- 3.6 to 13.1 +/- 5.4. BT-B can also be used successfully in CD patients not previously exposed to BT-A or BT-B (de novo patients). In our own nine de novo patients, 10436 +/- 3,320 mouse units of BT-B reduced the TWSTRS score from 18.4 +/- 5.4 to 9.2 +/- 4.8. Altogether, dryness of the mouth occurred in 21 CD patients (severe 10, moderate 7, mild 4), accommodation difficulties in seven, conjunctival irritation in five, reduced sweating in four, swallowing difficulties in three, heartburn in three, constipation in three, bladder voiding difficulties in two, and dryness of nasal mucosa, head instability, and thrush in one each. BT-B produces substantially more systemic autonomic side effects than BT-A. It can be considered the therapy of choice in antibody patients. For de novo patients and for BT-A-treated CD patients, BT-B cannot be recommended currently.