Drug used to treat clots can protect against cobra venom damage

Discover how a drug called tinzaparin could revolutionize snakebite treatment by reducing venom damage in cells.

Orange-red in colour and native to Tanzania, the Naja pallida — the red spitting cobra — is a formidable, 1.2-metre-long foe. When threatened, it raises its hood and hisses loudly. If this display doesn’t deter its predator, it opens its mouth. Muscles around the snake’s venom glands squeeze, releasing jets of venom onto the eyes, nose, and mouth of the threat. As the victim’s face sears in pain, the cobra takes the opportunity to lunge forward and bite, delivering a massive quantity of venom into the victim’s body.

The venom attacks cells in the body and damages the nervous system. For most of the cobra’s regular victims — toads, frogs, birds, and other snakes — the only fate is death. A lucky human might be spared but with a permanent disability.

Encounters with venomous snakes kill about 1.4 lakh people every year, especially in the tropical regions of Africa and Asia. Despite this alarming number, the treatment for snakebites has remained archaic.

Based on the work of French scientists in the late 1800s, antivenom is made today by injecting domestic animals like horses and sheep with small amounts of snake venom. This kicks the animal’s immune system into action, producing antibodies to neutralise the venom. Researchers extract these antibodies from the animal’s blood and transport them in cold storage to hospitals, where they are injected into the bodies of snakebite victims.

Difficulties in production, storage, transportation, and administration aside, antivenoms are also expensive and can have severe side effects in humans; some of them could be fatal.

That may soon change. In a July 2024 study published in the journal Science Translational Medicine, a team of Australian, British, Canadian, and Costa Rican scientists have reported that tinzaparin, a drug commonly used to prevent blood clots, significantly reduces damage to cells due to spitting cobra venom. The team also found the drug could reduce skin damage in mice injected with the venom.

According to a press release, the scientists have filed for a patent and may start human clinical trials soon.