An antivenom for scorpion sting is currently in the final phase of human studies in Mexico.
No antivenom specifically for scorpion stings is available.
The experimental antivenom named Anascorp, which contains a Centruroides immune F (ab) 2, is developed by Rare Disease Therapeutics, Inc.
Anascorp, an F (ab) 2 antibody, is being developed for the treatment of scorpion envenomation from the Centruroides scorpions. Centruroides sculpturatus is the only scorpion species with vertebrate neurotoxins whose natural range includes the United States.
When Anascorp was given to young children stung by bark scorpions in a small clinical trial in US, it was found that most of those given the investigational drug recovered within two hours. While those children who were given a placebo had symptoms that lasted four hours or more and required heavy sedation and hospitalization.
At present the safety and efficacy of Anascorp is being evaluated in an open label, multi-center, phase III trial.
Patients who arrive at the emergency clinic presenting with scorpion sting symptoms will be evaluated for treatment with Anascorp.
Approximately 100 patients could be enrolled in the study per year. Three vials of Anascorp will be administered in a total volume of 50 mL, intravenous over not less than 10 minutes or as permitted by IV access.
Twenty four hours and fourteen days after Anascorp treatment, all patients will be monitored for signs and symptoms of adverse events, including acute hypersensitivity reactions (anaphylactic and/or anaphylactoid reactions) and delayed serum sickness.
Centruroides scorpion is found in southeastern California, Arizona, Nevada, southern Utah, and southwestern New Mexico. It is also found throughout the Baja California Peninsula and western Sonora, Ensenada, B.C in México. A typical “bark” or “crevice” scorpion, C. sculpturatus is commonly encountered under rocks, logs, the bark of trees, and other surface objects.
Centruroides scorpion envenomation produces a pattern of neurotoxicity with a spectrum of severity ranging from the trivial to life threatening. Severe envenomation, more common in small children, may involve neuromotor hyperactivity, pulmonary edema, and ventilatory compromise occasionally resulting in death. Scorpions sting is estimated to afflict up to 10,000 people annually (of which 2,000 are small children).
Rare Disease Therapeutics, Inc. (RDT) is located in Nashville, Tennessee, USA. Rare Disease Therapeutics, Inc. is currently developing Orphan products, acquiring Orphan products through strategic alliances, and distributing Orphan products throughout the Americas. RDT works closely with the FDA Office of Orphan Product Development, National Organization for Rare Disorders, the National Institutes of Health, large international pharmaceutical companies, and patient advocacy groups to identify the unmet needs of patients with rare diseases and potential products to meet these needs.