New drug could stall deadly symptoms of rattlesnake bite
Officials said EMTs and hikers could carry the medication to help stall the spread of rattlesnake venom through the body
By Kara Carlson
Cronkite News via AP
TUCSON, Ariz. — As soon as a rattlesnake sinks its fangs into a victim, the venom starts traveling through the bloodstream. Within seconds, people can experience pain, swelling, bleeding and trouble breathing.
It's a race against time to get to a hospital, the only place that readily offers anti-venom. The longer it takes to get treatment, the higher the odds of long-term injury or death.
One University of Arizona doctor hopes to buy people more time before they get to the hospital.
Professor Vance Nielsen, the vice chair for research in the Department of Anesthesiology at the College of Medicine - Tucson, said his research could help stall the spread of rattlesnake venom through the body.
Nielsen is researching the potential of injecting a combination of carbon monoxide and iron in a rattlesnake bite area to slow the spread of venom. So far, he has made progress in rabbits, buying about an hour of time.
The idea is not to replace anti-venom, but extend the time patients have until they can get to the treatment.
Arizona has the highest rattlesnake bites per capita in the country. The Arizona Poison and Drug Information Center records 250 to 300 bites a year on average, but one official said that number is likely higher because people don't report all bites.
Keith Boesen, the center's director, said fatal rattlesnake bites are rare. Nationally, only about five bites a year lead to death, but survivors can have long-term injuries, such as loss of motion or strength.
There are 18 rattlesnake species in the United States. Boesen said 13 of those species call Arizona home — that's more types of rattlesnakes than in any other state.
"Because of this diversity, they live in different areas, so there's not really much of a rattlesnake-free zone in the state," Boesen said. "From the lowest point in the Grand Canyon to the highest mountaintop, there's probably a snake that can and does inhabit that area."
A rattlesnake's venom has more than 100 proteins that can cause damage near or around the bite site. It also can cause bleeding and neurological problems, Boesen said.
While anti-venom can stop the venom from spreading, it cannot heal any damage that has already resulted from the bite.
Nielsen's treatment creates blood clots that help slow the spread of venom by creating a barrier between the venom and blood.
Nielsen has tested it on rabbit blood, which coagulates similarly to humans. He also has had success with infected rabbits, but he has not tested effects past an hour. He plans to continue to test rabbits infected with venom.
If that's successful, he plans to move on to human clinical trials. However, developing a drug requires funding and company sponsorship. He anticipates the need for about $500,000 in funding for trials.
He said he's not yet sure how people will administer the treatment, but he believes a patch or injection would work best.
Nielsen said EMTs and hikers could carry the medication.
There's nothing on the market designed to help people between the bite and anti-venom, Boesen said. He added "wives' tale" treatments, such as sucking out venom, using ice or shocking the bite can actually make things worse.
"There's definitely a need for this technology to extend that life," said Rakhi Gibbons, associate director of biomedical and life sciences licensing for Tech Launch Arizona.
Tech Launch Arizona helps researchers obtain patents and connect with potential funders, and it's working with Nielsen.
It's crucial to patent work such as Nielsen's to guarantee research rights, gain a company's interest and develop a product.
Gibbons said they envision the product as an EpiPen-like injectable, and they're exploring the idea of veterinary options for pet owners.
"If we can add this product into their pipeline, that would go hand in hand with their particular anti-venom, it's a win-win for everyone," Gibbons said.
Even if it's picked up commercially, it may take years before the product hits the market, especially because it must meet U.S. Food and Drug Administration regulations.
"Typically, therapies in the biotech therapeutical world, they do have a long runway," Gibbons said. "For this therapy, we're at least seven to 10 years out."