Researchers from Indian Institutes of Technology , Delhi have developed, in collaboration with San Jose University in the US, an antivenom using an artificially designed peptide that effectively neutralises the poison of several snakes, including the four common in India — Indian cobra, common krait, Russell’s viper and saw-scaled viper.
The antivenom currently in use is a serum derived from horses immunised with snake venom. It is used against all four venomous snakes and costs around Rs 500 per vial. With the new anti-venom, IIT Delhi is aiming for a cost of $1 (about Rs 70) per dose. In India, an estimated 2.8 million people are bitten by snakes and 46,900 die of snakebite every year.
“This is a polyvalent anti-venom, which will be effective against a bunch of snake bites, unlike the ones currently available that are effective against only the big four. We have already shown its efficacy in two of the four snakes in mice model and the other two are underway,” said professor Anurag Rathore, department of chemical engineering in IIT Delhi.
The polyvalency of the single molecule will lower reactions to the other venoms present in the serum. “If the single molecule negates the effect of multiple venoms, it is a very important discovery. The serums in the market contain traces of all four venoms and carry the inherent possibility of reaction to venoms other than the one against which it is needed,” said Dr YK Gupta, former head of the department of pharmacology, All India Institute of Medical Sciences, which runs the National Poison Centre.
The peptide-based treatment will also remove the risk of an allergic reaction to horse serum.
Another advantage is its stability. “Serums are not very heat-stable and need to be stored in the correct cold-chain conditions for them to work. This makes transport and storage a problem in semi-urban and rural areas, where most of the snake bites occur,” said Rathore.
The maintenance of cold storage also drives up the cost of delivery. “The peptide-based treatment will most likely be in a powdered form, which is more stable than the serum and does not need cold storage. It can be mixed with saline at the point of administration. This, coupled with the method of production using DNA modified E coli bacteria, will result in the final product costing just one-tenth of the current anti-venoms,” he said.
“The availability of anti-venoms at the village or primary healthcare centre level is a problem because, at best, serums have a shelf life of eight months, leading to wastage. There are, of course, lyfolised antivenoms that have a shelf life of two to three years, but they are more expensive,” said Dr Gupta.
Courtesy: Anonna Dutt, The Hindustan Times