Botulinum Toxin: An Update on Pharmacology and Newer Products in Development

Since its introduction as a treatment for strabismus, botulinum toxin (BoNT) has had a phenomenal journey and is now recommended as first-line treatment for focal dystonia, despite short-term clinical benefits and the risks of adverse effects. To cater for the high demand across various medical specialties, at least six US Food and Drug Administration (FDA)-approved formulations of BoNT are currently available for diverse labelled indications. The toxo-pharmacological properties of these formulations are not uniform and thus should not be used interchangeably. Synthetic BoNTs and BoNTs from non-clostridial sources are not far from clinical use. Moreover, the study of mutations in naturally occurring toxins has led to modulation in the toxo-pharmacokinetic properties of BoNTs, including the duration and potency. We present an overview of the toxo-pharmacology of conventional and novel BoNT preparations, including those awaiting imminent translation from the laboratory to the clinic.

Automated summary

Botulinum toxin has evolved from a treatment for strabismus to the first-line treatment for focal dystonia, with at least six FDA-approved formulations available for diverse indications. These formulations have varying toxo-pharmacological properties and should not be used interchangeably. Synthetic and non-clostridial sources of BoNT are also nearing clinical use, and studies on mutations in natural toxins have led to modifications in the toxo-pharmacokinetic properties of BoNTs.