Scientists develop oral pill and lab-grown antivenom for snake bites

Scientists in Britain and Denmark are making progress on two new treatments for snake bites that could transform care for millions of people in poor rural areas. One approach is an oral pill that can be taken minutes after a bite, before a patient reaches hospital. The other is a lab-grown antivenom made from synthetic antibodies that works against 17 of the deadliest snakes in Africa.

More than 2 million venomous snake attacks are reported each year, causing around 140,000 deaths and leaving 400,000 survivors with permanent disabilities such as amputations, blindness and severe tissue damage. Most victims are farmers, women and children in rural Africa, South Asia and Latin America. India alone loses 58,000 people to snake bites every year. The World Health Organization classified snake bite as a neglected tropical disease in 2017 and set a target to halve deaths by 2030.

Current antivenom has not changed in over 100 years. It is made by injecting snake venom into large mammals like horses, then harvesting antibodies from their blood. This method is expensive, region-specific, and can cause severe allergic reactions, including anaphylaxis. Doctors are often hesitant to use it because of the risk of adverse reactions.

The team at the Liverpool School of Tropical Medicine is developing an oral pill made from existing drugs originally created for other diseases. The pill is designed to stop venom from causing tissue damage and internal bleeding. Because the drugs are already proven safe, the pill can be given outside a hospital at the point of bite. It is cheap, easy to store and easy to take. The researchers describe it as a synthetic chemical, similar to paracetamol, that works differently from traditional antivenom.

In Denmark, a separate team is growing antivenom in a laboratory. They inject venom into llamas and alpacas, which produce small antibodies called nanobodies. Scientists identify the best nanobodies, work out the DNA code, and insert it into specially grown cells to produce unlimited amounts of identical antibodies. This antivenom is given as an intravenous injection in hospital. In pre-clinical tests on mice, the mixture of antibodies worked better than existing antivenom, was more effective, and covered a broader range of snake species.

Both teams believe their work could save hundreds of thousands of lives. The Liverpool team is focused on a treatment that can be delivered at a local level, improving access for people far from hospitals. The Danish team aims to produce a safer, more consistent and cheaper antivenom that works across multiple snake species. The two approaches are complementary: the pill for immediate first aid, and the lab-grown antivenom for definitive hospital treatment.