By James Mitchell Crow – 2 May 2012
Snake venom has a place in several ancient medical traditions. As early as the 1930s western pharmacists began testing cobra venom as a treatment for conditions ranging from asthma to multiple sclerosis (Expert Opinion on Biological Therapy, vol 11, p 1469). But in recent years, modern techniques from mass spectrometry to high-throughput lab-on-a-chip bioassays have made life easier. Chemists can pick out and identify the specific venom components with beneficial effects, eliminating some unpleasant side effects and making the whole process safer.
One such component is now showing promise for treating multiple sclerosis. Quite what triggers MS remains unknown. What is clear, though, is that the body’s immune system begins to attack the insulating sheath that protects nerve cells, causing damage that can progressively impair sensory and cognitive function and movement. Bringing the immune system back into balance has proved very difficult, but a venom peptide called cobratoxin might hold the answer.
Last year, Florida-based firm ReceptoPharm had a patent approved for a version of cobratoxin chemically modified to remove its toxicity (US patent 8,034,777). The company claims that its modified peptide halted the development of MS in 90 per cent of laboratory rats with the rodent equivalent of MS. The peptide seems to stimulate the release of a messenger molecule called interleukin-27, which puts the brakes on an overactive immune response, bringing immune activity back down toward normal levels. ReceptoPharm is planning clinical trials to assess the compound’s efficacy in humans. Meanwhile, a related venomous molecule