Animal research* is based on the assumption that animals respond in the same way as humans when exposed to certain substances, and that complex human illness and healing processes can be mimicked by “animal models”, that is animals who have been made ill.The evidence is mounting that this assumption is wrong (see selective list of references below). We can never be sure that the results from animal research will be applicable to humans.
More and more researchers are speaking out about the limitations of animal research. For example:
In 2011, a group of scientists wrote an open letter in the medical journal The Lancet, addressed to the UK prime minister and health secretary, expressing concern about the increase in adverse drug reactions and the fact that more than 90% of drugs fail in clinical trials. This is largely due to an over-reliance on animal research to predict drug behaviour in humans. The scientists wrote that “[m]any studies have shown that animal tests frequently fail to translate to the clinic, with estimates of their ability to predict effects on people as low as 37—50%, or no better than the toss of a coin”.
The National Institutes of Health (NIH) is part of the U.S. Department of Health and Human Services and the nation’s medical research agency. Elias Zerhouni, the NIH Director from 2002-2008, recently made the following statement about the usefulness of animal research:
We have moved away from studying human disease in humans, he lamented. “We all drank the Kool-Aid on that one, me included.” With the ability to knock in or knock out any gene in a mouse—which “can’t sue us,” Zerhouni quipped—researchers have over-relied on animal data. “The problem is that it hasn’t worked, and it’s time we stopped dancing around the problem…We need to refocus and adapt new methodologies for use in humans to understand disease biology in humans.
Animal research is scientifically outdated and alternatives are available. For example, the UK’s Dr Hadwen Trust observed that “[a]lternatives to animal experimentation are now available in virtually every field of medical research”.
Currently available alternatives to animal research include, for example:
- in vitro research (using tissue and cell cultures)
- human tissues
- a greater focus on prevention
- epidemiology (the study of human populations)
- computer modelling
- organ-on-a-chip models.
Approximately 7 million animals are used in research and teaching in Australia every year. What a waste of resources. How regrettable that this only distorts the research that seeks to find cures for human diseases such as cancer and Alzheimer’s. Could we have missed out on a vital cure for a disease because a drug was unsafe or ineffective in animals, but would have worked for humans?
Not counting the evidence for the futility of animal research, many people consider using animal in research to be unethical. But that’s for another post.
* I use the term “animal research” to mean using animals in research conducted to advance human health. This includes using animals as models for studying human biology and disease (basic research), and as test subjects for the development and testing of drugs and vaccines.
I have written about this topic in the Conversation: “Animal research provides a flawed model, so why not stop?” and on the Croakey blog: “Another challenge to the mouse model”.
(Some of the articles below are behind a pay wall. If you contact me I might be able to send you a copy for study purposes)
Couzin-Frankel, J. (2013). When mice mislead. Science, 342(6161), 922-925.
Goodman, J. R., Borch, C. A., & Cherry, E. (2012). Mounting opposition to vivisection. Contexts, 11(2), 68-69.
Knight, A. (2007). Systematic reviews of animal experiments demonstrate poor human clinical and toxicological utility. Alternatives To Laboratory Animals, 35, 641–659.
Leist, M., & Hartung, T. (2013). REPRINT: Inflammatory findings on species extrapolations: humans are definitely no 70-kg mice. ALTEX, 30(2), 227 – 230.
Perel, P., Roberts, I., Sena, E., Wheble, P., Briscoe, C., Sandercock, P., et al. (2006). Comparison of treatment effects between animal experiments and clinical trials: systematic review. British Medical Journal, 334(7586), 197.
Pound, P., Ebrahim, S., Sandercock, P., Bracken, M. B., & Roberts, I. (2004). Where is the evidence that animal research benefits humans? British Medical Journal, 328(7438), 514-517.
Seok, J., Warren, H. S., Cuenca, A. G., Mindrinos, M. N., Baker, H. V., Xu, W., et al. (2013). Genomic responses in mouse models poorly mimic human inflammatory diseases. Proceedings of the National Academy of Sciences.
Shanks, N., Greek, R., & Greek, J. (2009). Are animal models predictive for humans? Philosophy, Ethics, and Humanities in Medicine, 4(1), 2.
van der Worp, H. B., Howells, D. W., Sena, E. S., Porritt, M. J., Rewell, S., O’Collins, V., et al. (2010). Can animal models of disease reliably inform human studies? PLoS Medicine, 7(3), e1000245.