Synthetic antivenoms for snakebites: A slithering road!

Abstract

Since Adam and Eve, humankind has been equally frightened and fascinated by snakes. The ancient Egyptians worshipped the cobra, which decorate sarcophagi and the famous mask of Tutankhamun. Even today, the snake is integral to the Staff of Asclepius, a symbol of medicine. To some extent, medicine has forgotten about the snake, however, bites from venomous snakes still pose a deadly impact on people in low-and middle-income countries. It is estimated that venomous snakes kill between 81,000 and 137,000 people every year, and maim around 400,000, which represents a huge impact both on families and social economics. Around 125 years ago, Calmette began to produce antivenom serum for snakebite victims. Since then, production methods have not changed significantly; then and now, antivenom is made by immunizing animals. Isolated antibodies can neutralize some of the most lethal toxins, thereby saving many lives. However, there is still a need for animals such as horses or sheep, as well as a snake farm, in order to acquire enough venom for immunization procedures. Animal-derived antibodies pose a threat, because they are foreign components injected into the human body, which can give rise to adverse immunogenic reactions. In a worst-case scenario this can lead to anaphylactic shock and death. Synthetic antivenom, is an interesting avenue, which could reduce or entirely remove the need for immunized animals and snake farms. Synthetic antivenoms could be made to high purity and eliminate many current challenges, such as batch-to-batch variations, high costs, limited shelf life and the need for 'cold-chain' transportation.