Horseshoe crab blood is a staple in the medical industry. It has a unique property that makes it perfect for testing medical materials for bacterial and viral contamination. But about 50,000 horseshoe crabs die every year in the blood harvesting process.
A synthetic alternative to horseshoe crab blood was patented 15 years ago. But pharmaceutical companies are only just starting to make the switch.
The synthetic alternative to horseshoe crab blood is called factor C. It was invented by Jeak Ling Ding, a Singaporean molecular biologist. A hospital fertilization department recruited Ding to solve a problem: Their embryos were not surviving. They suspected bacterial contamination may be the culprit.
Ding's first idea was to test the clinic's embryos for contamination using horseshoe crab blood. This type of test, known as an LAL test, is standard in the medical industry for checking all drugs and implanted medical devices — aka anything that will go into a human body. However, Ding found that the LAL embryo testing kits were too expensive: $1,000 a pop.
So, Ding set out to make her own synthetic version of horseshoe crab blood. After 15 years of trial and error, she finally succeeded.
Ding's synthetic alternative first became available in 2003, but pharmaceutical companies were not interested in making the switch from horseshoe crab blood. Why?
The first reason is that only one company — a Switzerland-based company called Lonza — was producing the alternative. Pharmaceutical companies didn't want to rely on a product that only had one producer, especially since the product is absolutely essential to their own production process.
The second reason has to do with FDA regulations. It wasn't until 2012 that the FDA officially released new testing guidelines that said pharmaceutical companies could use factor C. But the pharmaceutical companies would have to perform their own validation tests on factor C (basically testing to ensure factor C works just as well as LAL).
If the FDA does not accept a company's validation test, the drug they want to sell won't get approved. That's a risk no company wants to take.
In 2013, another company called Hyglos began producing factor C. This gives pharmaceutical companies more options and more reason to use the new alternative.
Another major development is that the European Pharmacopoeia officially deemed factor C an accepted bacterial-toxin test in 2016. This move may encourage the FDA to follow suit.
A third factor is that horseshoe crab populations have been declining in Asia.
Drug manufacturers in China may soon have to use the alternative, because certain protections for the species may be put in place.
Drug company Eli Lilly recently sent the FDA its first application for a drug that will be tested using factor C, and the company has also been lobbying to make factor C an approved quality test, with no validation required.
Horseshoe crabs may have a brighter future, where they are no longer unnecessarily exploited.