Anvenom Approved by FDA For Treatment Of Scorpion Stings

Bark Scorpion of Arizona, photo courtesy of Musides at en.wikipedia, CC BY-SA 3.0The Food and Drug Administration (FDA) recently approved an antivenom product, Anascorp­ for the treatment of scorpion stings. From an Associated Press report, the FDA "says it will permit the use of Anascorp to treat stings by Centruroides scorpions, which live mostly in Arizona." The Centruroides scorpion of greatest concern in the U.S. is the bark scorpion, Centruroides exilicauda.

My friend and scorpion expert, Dr. Jeffrey Suchard, has added the following (paraphrased) information to his chapter on scorpion envenomation, which will appear in the forthcoming 6^th edition of the textbook Wilderness Medicine:

Although no manufacturer in the U.S. is currently producing any scorpion antivenom, research has been conducted in Mexico using a horse host and venom from other Centruroides species. Anascorp, Centruroides (Scorpion) Immune F(ab’)2 (Equine) Injection, manufactured by Instituto Bioclon, S.A. de C.V., of Tlalpan, Mexico, D.F., was approved as an orphan drug by the U.S. Food and Drug Administration on August 3, 2011, based upon safety and efficacy data collected on 1534 patients in a study coordinated by investigators from the University of Arizona.

This antivenom is to be marketed to healthcare facilities in areas where Centruroides sculpturatus is found, which includes Arizona, and portions of Clark County, Nevada and New Mexico.”

In the study mentioned, patients who received antivenom for scorpion sting had much-improved clinical courses (faster relief from clinical symptoms) than did persons treated with placebo. Because a scorpion sting can be such a distressful event, this is very good news for persons envenomed (stung) by scorpions who will have access to the antivenom.

This is additional quoted information from Leslie Boyer, director of the University of Arizona’s VIPER (Venom Immunochemistry, Pharmacology and Emergency Response) Institute and lead investigator on the clinical trials: "It's the first time a drug was developed fully in Latin America and subsequently approved by the FDA. It is the first-ever scorpion antivenom proved effective under controlled clinical trials, and the first-ever antivenom with so few allergic reactions.”