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Scientists have long known that venom from the southern copperhead, native to the Eastern U.S. and Mexico, contains a powerful clot buster. In the mid-1990s, a team led by biochemist Francis Markland, of the University of Southern California, discovered that the venom may also fight cancer.
The venom contains a protein, contortrostatin, that retards the growth and metastasis of tumors. Markland's team has found that injections of contortrostatin not only prevent the spread of ovarian and breast tumors in mice but also shrink them as much as 75%. The group hopes to start clinical trials of contortrostatin in about two years.
Cone Snail
The tropical oceans harbor more than 500 species of cone snails, predatory creatures that stab their prey with harpoons loaded with a paralytic poison. Long prized by shell collectors, they are being scrutinized by drug hunters for potential treatments for neurological and neuromuscular disorders.
Each species of cone snail produces a unique venom that contains between 50 and 200 pharmacologically active peptides known as conotoxins. The most advanced conotoxin-derived drug in development is Elan Corp.'s Ziconotide, a nonaddictive treatment for severe chronic pain that is awaiting FDA approval. Cognetix, based in Salt Lake City, Utah, recently started clinical trials on a possible epilepsy treatment. Also in the works: potential therapies for schizophrenia, stroke and Parkinson's and Alzheimer's diseases.
Terciopelo Snake (Fer-de-Lance)
Pit-viper venoms--particularly those from the genus Bothrops, of which the Central American terciopelo snake is a member--contain compounds that closely resemble substances used by white blood cells to fend off bacterial infections. Some of these substances work by damaging or disrupting lipids within the bacterial cell wall. A decade ago, microbiologists Edgardo Moreno, of Costa Rica's National University, and Bruno Lomonte, of the University of Costa Rica, realized that a muscle-destroying toxin in terciopelo venom behaved the same way.
The two scientists have since isolated at least 10 microbe-fighting myotoxins from various viper venoms and synthesized nontoxic versions of them in the lab. They are talking to drug companies about doing additional research in animals and, eventually, people. If those studies pan out, Moreno says, viper-venom antibiotics could be put in everything from mouthwashes to contact lenses to fight salmonella, cholera, staph and strep.
Giant Israeli Scorpion
Chlorotoxin, a substance in the venom of the giant Israeli scorpion, a 5-in.-long species known as the "death stalker," may offer hope for the 25,000 Americans each year who have glioma, an incurable, rapidly spreading form of brain cancer. Surgery provides only a temporary respite, and the few experimental therapies extend a patient's life span only weeks.