Animal venoms have recently become a hot commodity in the medical field for therapeutic use because of their overall potency and molecular specificity. Increasing research related to the human immune and nervous systems have brought this technology to the forefront. The first venom-derived drug (for hypertension) was approved by the FDA about 30 years ago and only a couple others since then have been approved. One of the most recent drugs that is in development right now comes from the sun anemone, Stichodactyla helianthus, that lives in coral reefs of the Caribbean Sea.
In the many toxins that these anemones release, one was found that inhibits the T lymphocyte potassium channel which is involved in the human immune response. This particular toxin, called ShK, is a candidate for autoimmune therapeutics. This toxin can not be used in it’s native form however, because in addition to blocking the T lymphocyte potassium channel it also blocks another potassium channel associated with neurons. After making almost 400 synthetic derivatives of the ShK toxin, a version was finally settled on that contains one additional amino acid to make sure that the neuronal potassium channel is not blocked. This derivative is known as ShK-186 and has been used in rodent models for the treatment of multiple sclerosis. In December of last year, the first humans trials were conducted on healthy volunteers by a Seattle-based biotechnology company. Although the results from this initial trial have yet to be released to the public, one of the physiologists working with the compound stated that the team was “very happy with the results.” He also added that second phase human trials were due to begin in April of this year. This breakthrough in the use of venom-derived drugs is exciting because it holds such promise and may be used for the treatment of a wide range of autoimmune diseases in the near future.