When it comes to pharmaceuticals, testing on animals is a terrible but necessary evil. Life-saving drugs continue to be developed every year, but to reach the market they are subjected to rigorous safety testing to ensure they pose no safety risk to humans. Our current best way of doing this is by testing them in animal models – be it mice, rabbits, or primates. 

But what if there was a way we could ensure drugs were safe for human consumption, but harm no animals in the process? 

Researchers from Hebrew University of Jerusalem, Israel, believe it’s possible – and they’ve already demonstrated it by producing a promising cancer therapy without testing on a single animal. Using a chip with human tissue on it, the researchers believe they can demonstrate safety and efficacy while bypassing the traditional animal testing stage, and have now submitted their new drug to the US Food and Drug Administration for approval. Their results were published in the journal Science Translational Medicine.

The therapy itself aims at combatting the buildup of fat in the livers of patients that take certain drugs, specifically anti-cancer drugs such as cisplatin and the immunosuppressive drug cyclosporin. These drugs induce nephrotoxicity, which accounts for around 14 to 26 percent of impaired kidney function in people being treated for acute kidney injury. When looking at a prospective cohort study, the researchers found that people receiving cisplatin or cyclosporin in combination with another drug, empagliflozin, showed significant improvement in kidney function. They suggest that empagliflozin could be used as a tool alongside these important drugs to limit the damage they may have on the kidney and other organs. 

However, the therapy they have created is not necessarily the star of the show. What was so remarkable about this study is the fact the researchers may have created a viable and safe therapy without any animal testing whatsoever. Using a biological chip, the researchers uncovered the mechanism of empagliflozin in helping against nephrotoxicity and validated the drug's efficacy.

“To our knowledge this is the first time a drug is taking this step without animal testing, and the reason is that we have eliminated this need by using our ‘human on a chip’ technology,” Professor Yaakov Nahmias, lead author, told The Times of Israel. 

"This is the first demonstration that we can use such technology to circumvent animal experiments, and this could lead to faster, safer and more effective drug development. Getting a drug to the point of clinical trials normally takes four to six years, hundreds of animals and costs millions of dollars."

“We’ve done it in eight months, without a single animal, and at a fraction of the cost.” 

To mimic how the drugs would interact in humans, they used human kidney spheroids – a spherical cell culture – embedding microsensors to analyze the metabolism of the tissue. This biological "chip" allowed them to test their therapy and get real-time results without the use of animal models.  

With this being the first drug to go through to approval without animal testing, if successful, this study could be a breakthrough in reducing the number of animals used in labs. With various technologies that simulate drug interactions leaping to the foreground recently – including organoids, computer simulations, and more – it may be very possible that the future of animal-free drug testing is closer than we think.