Antitoxin therapy for botulinum intoxication

Botulinum toxin is the most toxic substance known to mankind. It is involve d in infant botulism, classical food-borne botulism, wound botulism, and is a threat in biological warfare or bioterrorism. The only successful drug c urrently available to treat botulinum intoxication is equine antitoxin, and there is potential for much improvement of this product. This review discu sses the factors that could be changed to improve the safety and efficacy o f botulinum antitoxins. The host species could be changed from horses to ot her animals such as sheep or goats, in order to lower the immunogenicity of the antiserum. The choice of immunogen is extremely important in improving : the potency of the product. Fractionation of the antitoxin and affinity p urification are two further ways in which the safety and potency of the pro duct could be increased. The current botulinum antitoxin assay has a lethal endpoint, and several more humane assays for antitoxin are discussed. The dosing level for botulinum antitoxin is excessively high when the amount of toxin involved in intoxication is so small. Optimising the dosage of antit oxin would further improve the safety of the product. The therapeutic windo w of the current product is also discussed, along with potential mechanisms of increasing the therapeutic window. (C) 2001 Lippincott Williams & Wilki ns.