The case against animal experimentation is strong as we have both ethics and science on our side!

Animal testing fails over 90% of the time.

‍Below, you can find scientific evidence that backs this claim.

Animal tests are often conducted to try and prevent dangerous or ineffective new drugs from reaching human trials. We can see how well this is working by looking at the overall failure rates. I.e., the rate at which a potential drug shows promising results in animal tests but then fails in human trials.

‍Spoiler alert: it isn't working well.

Studies and reports that highlight this shocking failure rate:

1. A review of the U.S. Food and Drug Administration (FDA) figures reported a 96% failure rate despite efforts to make animal studies more effective.¹

2. A 2014 review concluded that more than 90% of new drugs that seem to be safe and efficacious in animal tests are not effective in human trials and do not make it to clinical use. This review also states:

‍“Given the large amount of animal research being undertaken, some findings will extrapolate to humans just by chance.”²

3. In 2019, Nature Reviews reported an average failure rate of 93% to 94% for new substances.³

4. A pharmaceutical analysis company reported an average failure rate of 90.4% to 92.1%. For cancer research, this was as high 96.4%.⁴

5. A 2018 analysis of the shortfalls in drug development found that the results from legislation-mandated animal tests in the early stages of drug development were hindering the cost-effectiveness of research. Leading to a 90% failure rate for new drugs entering human trials. The authors deemed animal tests as misleading, noting these drugs “have little chance of being safe and effective for humans and, in fact, have a high chance of being harmful”.⁵

6. The US National Center for Advancing Translational Sciences states the following on its website:⁶

"About 90% of the promising therapeutic candidates that enter clinical trials fail because the 2-D cell cultures and animal models — the current drug development approaches for safety and efficacy — don’t capture the complexity of human tissues and don’t translate well into predicting people’s response to candidate therapies.”

7. A review of data from 2000-2015 reported failure rates of different data sets⁷, including:

• An average failure rate of 94.3% from their own analysis.
• A failure rate between 81% and 90.4% based on literature.

8. A large meta-analysis investigated 101 original drug research articles that used animal models, published from 1979 to 1983. Of these, only about half even resulted in further published research within 20 years, and only five drugs were licensed for human use (equaling a failure rate of 95.1%). Only one of the 101 has shown an extensive clinical advantage (equaling a failure rate of 99%).⁸

9. A 2015 study using the U.S. National Institutes of Health (NIH) drug database analysed 1,079 drugs, yielding a failure rate of 76% and 94% for compounds developed with and without biomarkers, respectively.⁹

10. Using public sources and commercial databases, researchers gathered data about late-stage clinical trials between 1998 and 2008 (meaning these drugs had already passed initial tests on healthy humans at lower doses). A total of 54% of drugs failed at these later stages, mostly due to inadequate efficiency (57% of the failures) and safety concerns (17% of the failures).¹⁰

11. In Alzheimer's disease research using animals resulted in:

• 99.6% of new medications developed in animals failed in humans between 2002 and 2012.¹¹‍
• Only two Alzheimer’s drugs have been approved since 2004 (based on a review from 2022)!¹²

12. Even on the website of an organisation vigorously defending animal-based research, we’ve found data proving this high failure rate! The data they cited was taken from a market research company, and the summed-up failure rate was 93.4%. They also state that of all the drugs passing the first clinical trials in humans, 86% will fail in later trials.¹³

13. Researchers at the University of Zurich, Switzerland, meta-analysed over 100 publications investigating the success of animal-to-human translation of therapies. They identified that only 5% of positive outcomes in animal testing result in regulatory approval.¹⁴

With such high failure rates being shown consistently across different areas of medical research, it’s clear that the current system is broken.

The good news - animal-free research is proving to be the superior option!

Here are some examples:

• Researchers found that animal tests were able to identify 75% of a set of 64 toxic substances, while a computer model (animal-free method!) could identify 89%.¹⁵‍
• Biological lab tests based on human skin predicted 70-76% of human results, compared to a mere 56% using the traditional rabbit experiment.¹⁶‍
• Liver-on-a-chip technology was able to identify 87% of liver-damaging drugs that had before passed animal testing, and the chip labeled all of the safe drugs correctly.¹⁷