Botulism Antitoxin Effects on Paralysis Induced by Botulinum Neurotoxins in the EDB Muscle

Botulism is a rare disease; however Botulinum toxins (neurotoxins) may be used as biological weapon especially in the form of aerosol. Botulism is caused by neurotoxins that are produced by the obligate anaerobic, gram-positive, spore-forming bacterium Clostridium botulinum (1). C. botulinum produces 8 serologically distinct neurotoxins identified as serotypes A, B, C1, C2, D, E, F, and G (2). Therapy for botulism includes supportive care and passive immunization with antitoxin. Antitoxin should be administered to patients with neurologic signs of botulism as soon as possible after clinical diagnosis (3). Botulism antitoxin is prepared from plasma obtained from horses that have been immunized with a specific subtype of botulism toxoid and toxin. The BT-002 is an exploratory pharmacodynamic study that is being performed to evaluate the effect of Botulism Antitoxins in preventing paralysis of extensor digitorum brevis muscle following BOTOX®/ MYOBLOC® administration. This study will compare bivalent and heptavalent products to a placebo. Safety data will be collected. NP-018 (heptavalent equine-derived botulinum antitoxin) is prepared from plasma obtained from horses that have been immunized with a specific subtype of botulinum toxoid and toxin. Each individual horse is immunized against a single botulinum toxin subtype. Plasma is pooled from horses that have been immunized with the same botulinum toxin subtype. For each antitoxin serotype (A-G), a despeciated product will be produced by pepsin digestion of the IgG monomer in the equine plasma, yielding predominantly F(ab')2 fragment. Following the formulation, the seven antitoxin serotypes will be blended into a heptavalent product and filled into single-use vials. ' This research study will be conducted in two stages - Stage A and Stage B. If enrolled in the Stage A of the study, the subject will have an equal chance of getting either bivalent botulism antitoxin or placebo. If enrolled in Stage B of the study, the subject will have an equal chance of getting heptavalent botulism antitoxin (NP-018) or placebo. The subject will be receiving injections of Botox and Myobloc on the next day after the antitoxin administration in the left and right foot respectively. The subject's participation in this study will be for maximum of 57 days.