RimabotulinumtoxinB: An Update

Abstract

BACKGROUND Botulinum type-A toxin is a well established aesthetic and medical treatment. While the usage of type-B toxin is less common, there is a growing interest in using type-B toxin, especially in those who are treatment resistant. OBJECTIVE To evaluate the primary FDA-approved clinical applications of rimabotulinumtoxinB, along with established and emerging off-label clinical indications. MATERIAL AND METHODS Articles were reviewed from PubMed database and Food and Drug Adminstration guidelines. RESULTS Facial rhytids tend to use a higher conversion ratio between type A and type B toxin, due to type B toxin's weaker affinity to muscles and higher affinity for sweat glands. Specially, a 1:100 to 1:50 ratio was utilized for glabellar rhytids, a 1:25 to 1:50 ratio for periocular rhytids, a 1:50 to 1:66.6 ratio for cervical dystonia, a 1:20 to 1:50 ratio for hyperhidrosis, and a 1:25 to 30 ratio for sialorrhea. CONCLUSION Type B toxin has demonstrated its safety and efficacy in treating facial rhytids, cervical dystonia, sialorrhea and hyperhidrosis, with potential for novel applications under investigation. Regardless of injection location and clinical applications, dry mouth and dysphagia remained the most common side effects. Across all indications, type B toxin appeared to have a faster onset of action, a dose-dependent clinical duration, and a dose-dependent adverse effect profile.