When news broke that a group of grad students had produced lab-grown snake glands, , it was recognized as an interesting new approach. I and many others with decades of experience in the venom and antivenom industry understand the potential of such a novel approach. That is, a world in which venom proteins as medical agents or immunogens are produced in labs, rather than by the arduous process of extracting (what some erroneously call “milking”) venom (proteins) from snakes.
Yet in the understandable interest around this novel approach, we should not lose sight of why the antivenom production process is so arduous in the first place. In fact, in many ways this process is the product, for the unavoidable reality remains that delivering consistently high-quality antivenom takes significant time, effort, and investment.
Why producing quality antivenom is such a challenge – and how we do it
One of the major challenges in producing antivenom is that venom is not one thing, but rather a complex mixture of as many as 20 to 25 proteins – many of which are part of complex families of proteins. Some of these proteins are enzymes and peptides that damage cells and tissues, some affect how the blood clots, and others are neurotoxic, affecting the neuromuscular and peripheral nervous system. These protein components can vary from species to species, and even by the age or geography and habitat of the snake.
Therefore, the World Health Organization (WHO) guidelines state that the ideal and most effective antivenom should be derived from snakes that are representative of the snake population living in the area where the antivenom is being used.i
To account for geography and variation between species, effective therapies are made by extracting venom from a carefully selected sample of snakes local to where the antivenom will be used. The venom proteins of these snakes are then used to generate a broad range of antibodies capable of treating the range of envenomations that patients might suffer.
Our process, for instance, uses venom from four species of pit vipers native to the US to generate four sets of antibodies that are affinity purified and ultimately blended into a single antivenom. We periodically refresh this diverse colony of snakes to ensure our sample is representative of the snakes that hikers, bikers, gardeners and other outdoor enthusiasts might come across. This process is time, labor, and cost-intensive, but at present it is the only way to manufacture a product that can be relied on to treat all North American pit viper envenomation.
And so, while proteins from an artificial laboratory snake gland are undoubtedly an exciting academic research development, one artificial snake gland – of one snake – will not produce broadly effective antivenom on its own. It is only the first step. Preparing medicines for consumer use requires rigorous clinical testing, robust manufacturing processes, stringent quality controls, and an unfailing, often global, supply chain.
That said, we are always seeking new ways to innovate on our treatments, and we continue to follow these and other research developments closely.
In the meantime, we will continue putting in the time, resources, and effort required to produce our high quality antivenom.
i World Health Organization. WHO guidelines for the production, control and regulation of snake antivenom immunoglobulins. https://www.who.int/bloodproducts/AntivenomGLrevWHO_TRS_1004_web_Annex_5.pdf. Accessed March 9, 2020.