Long-term safety, efficacy, dosing, and development of resistance with botulinum toxin type B in cervical dystonia

✍ Scribed by Brian Berman; Lauren Seeberger; Rajeev Kumar

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 64 KB
• Volume: 20
• Category: Article
• ISSN: 0885-3185
• DOI: 10.1002/mds.20290

✦ Synopsis

Abstract

Short‐term studies of cervical dystonia (CD) have demonstrated botulinum toxin type B (Bot B) to be safe and efficacious at doses of 5,000 to 10,000 units, but few long‐term studies have been published and the safety and efficacy of higher doses has not been established. Additionally, there are few studies describing the development of resistance to Bot B in those with and without prior resistance to botulinum toxin type A (Bot A). We reviewed our experience with 24 patients treated with Bot B for up to 64 months. Patients were treated with Bot B for 26.2 ± 20.4 months (range, 3–64 months) with a mean treatment dose of 14,828 ± 6,824 units (range, 2,500–28,000 units). At last follow‐up, 12 patients demonstrated ongoing benefit, 8 patients had become secondarily resistant, and 4 patients were primary nonresponders possibly due to the severity and nature of their CD. Nine of the 12 continued responders and 7 of the 8 secondary nonresponders to Bot B had prior probable or definite clinical resistance to Bot A. No severe adverse events related to Bot B were seen. Treatment of patients with severe CD who continue to show a beneficial response to Bot B injections commonly requires doses of 15,000 units and rarely greater than 20,000 units. Patients may continue to respond for up to 64 months. Prior Bot A resistance may be a risk factor for the development of resistance to Bot B; nevertheless, Bot B can be a useful long‐term alternative in some Bot A‐resistant CD patients. © 2004 Movement Disorder Society