27 Oct Animals as Medical Research (Vivisection)
A commonly used phrase in the medical research and pharmaceutical industries is that animal testing is an “unfortunate necessity”. This widely accepted phrase is simply incorrect. While animal testing is certainly “unfortunate”, it is by no means a “necessity” for improving human health. In fact, animal testing for medical research, also known as vivisection, could actually be detrimental to humans.
Non-human animals are NOT good models for human disease
“They are so ingrained in trying to cure mice that they forget we are trying to cure humans”. – Dr. Ronald W. Davis, genomics expert, Stanford University.
The most fundamental biological principle as to why animal testing does not work is, quite simply, animals are not smaller versions of humans. Animals, though genetically very similar, have distinct physiological differences to humans that make it impossible to draw links between the two.
The fact is this; animals do not develop human diseases. And the complex mechanisms by which human diseases occur cannot be replicated in animals. This is why so many animal models are cured of diseases with treatments that do not work in humans.
This effect becomes even more pronounced when an animal is in a stressed environment, such as a laboratory. In these environments, animal physiology changes, and the way they respond to disease is different to how they would respond in a natural environment. If, even in the best circumstances, animal models cannot translate to humans, how could they in an environment where they cannot even translate to the rest of their species?1
“Ask the experimenters why they experiment on animals, and the answer is: ‘Because the animals are like us.’ Ask the experimenters why it is morally OK to experiment on animals, and the answer is: ‘Because the animals are not like us.’ Animal experimentation rests on a logical contradiction.” – Dr. Charles R. Magel.
Did you know that 92% of drugs that pass pre-clinical testing (of which vivisection makes up a large part) then go on to fail in humans, either because they are ineffective or unsafe?2 More recent studies indicate this number could be closer to 96%.3 Imagine if a surgery that was recommended by national guidelines had a failure rate of 90%. There would, rightly so, be outrage. Yet this is the failure rate associated with the current recommended methods of drug development. These odds would be unacceptable in any other facet of medicine, so why is animal testing any different?
“Animal studies are done for legal reasons and not for scientific reasons. The predictive value of such studies for man is meaningless.” – Dr James D. Gallagher, Director of Medical Research, Lederle Laboratories.
Toxicology is a field of medical science that investigates how toxic or carcinogenic chemicals are to humans. It is based on the assumption that the physiology of non-human animals is sufficiently similar to human physiology to produce results that are replicable between species. There is now a large, and still growing, body of evidence to suggest this is not the case.4 For example, an animal bioassay is considered the gold standard for identifying cancer-causing chemicals. This bioassay involves mice and rats to be exposed to maximally tolerated doses of chemicals for two years and costs millions of dollars for each assay. It also has a positive predictive value of 20%.5 This means that only 20% of chemicals that are identified as definite or probable carcinogens in rodents actually are in humans. Again, imagine a surgery with an 80% chance of failure. Would you accept those odds?
Similar results have occurred when other methods of toxicology have been analysed, simply because translating physiological results from one species to another is scientifically flawed.6-8
HARMS TO HUMANS
“We have cured mice of cancer for decades–and it simply didn’t work in humans.” – Dr. Richard Klausner, director of the National Cancer Institute 1995-2001.
There is no shortage of examples of cases in which vivisection has caused direct harms to humans. The TGN1412 disaster in 2006 is one such example. TGN1412 was an experimental therapy being trialled for use in autoimmune conditions, designed to dampen down the immune system. In it’s pre-clinical phase it had been tested in mice, rats, rabbits, and even certain strains of monkeys specifically chosen because of the similar way to humans TGN1412 acts in the body, at doses of 400 times the amount you would give to humans. Despite this thorough pre-clinical testing, within minutes of this compound being administered in the human volunteers, severe side effects were observed. The compound acted in the opposite way to what was observed in animals, and instead amplified the immune response. All volunteers went to hospital in severe pain, one had dramatic head swelling, and several ended up with permanent organ damage.9
Possibly even scarier than the direct harms caused to humans by vivisection are the indirect harms. If so many cures have been found for diseases in animals that do not work in humans, it then logically follows that there would be many cures that would work in humans but do not work in animals. Unfortunately, with the setup of the system at the moment, these potential cures would have been discarded at the pre-clinical phase and their potential for cure in humans unexplored. There have already been examples of anti-cancer drugs (tamoxifen, Gleevec) that caused liver toxicity in rats but were persevered with due to promising results in human cell cultures and are now huge parts of cancer therapy.
Another indirect harm of vivisection is the misplacement of research funds. As anyone in the medical research world would know, funding has never been harder to find than it is now. In the US, the National Institute of Health spends half its funding on animal experimentation. Most of these experiments will not have a dramatic impact on human health, for the reasons stated above. Surely this funding can be funneled into more resource-efficient areas in order to have the best outcomes for human health.
Another resource that is being misplaced with vivisection is time. All research takes time, but animal experimentation often takes many, many years for any conclusions to be drawn, whether they be positive or negative. In the meantime, people are suffering from diseases that may not (in fact, most likely not) even benefit from the results of the research in the first place.1
HARMS TO ANIMALS
“It [referring to dog labs] did more to damage my identity as a physician than anything else. I learned nothing physiological. I learned that life is cheap, and that misery can be ignored.” – Dr. Murray Cohen, MD.
Talk to most researchers who use animals in Australia and they will tell you about the stringent ethical guidelines they have to adhere to, the 20-page ethics approval they first have to complete before they can even touch an animal, the 3R’s (replacement, reduction and refinement) that they quote as if by doing so no animals are harmed. But even the most passionate supporters of vivisection cannot deny that it is not in the best interests of the animal. This is why they label vivisection not just as a necessity (though of course this too is false), but also as an unfortunate one.
Who is animal experimentation?
They are Britches, the baby monkey who was taken from his mother and had his eyes sown shut at birth to investigate maternal deprivation and childhood blindness in a study methodology that provides little clinically useful information.
They are the lambs shaken to death to replicate child abuse when the results of the study could have, and already had been, deduced from the examination of human cases.
They are the cats whose spinal cords have been crushed as a model for spinal cord injury, and the rats and mice whose brains are literally picked apart to create a model for dementia, a disease which only exists in humans and is unlikely to be cured in animals.
They are the dogs who have never known love or companionship but are still so trusting that they lick the same hands that poison them.
115 million animals are used in research worldwide every year. They are kept in miserable conditions, subjected to horrible procedures and suffer every single day of their lives. Supporters of vivisection seem to believe that we have to choose between human and animal well-being in order to achieve medical progress. Luckily the reality is far simpler than that, and what is best for the animals is also what is best for humans.10
“We sacrificed daily from one to three dogs, besides rabbits and other animals, and after four years experience, I am of the opinion that not one of these experiments on animals was justified or necessary.” – Dr. George Hogan.
If animal experimentation is abolished, those millions of dollars currently being spent on the industry can be put towards promising alternatives that are increasingly being used. “Alternative” in medicine is a dangerous word due to its pseudo-scientific connotations, but these alternatives to vivisection are based on real science and certainly better science than the fundamentally flawed concepts upon which vivisection is based.
Some of these alternatives are already being used in conjunction with animal testing. The issue with continuing this practice is that human-based tests and animal-based tests frequently result in different conclusions. When this happens there is no way of knowing which results are accurate, and more often than not the results from the animal testing are deemed to be correct for reasons that are more historical than scientifically justifiable.
In vitro experiments, informally known as “test tube” experiments, are experiments in which the reactions of cells to stimuli are observed. When human-based cells are used in toxicology, for example, they have been proven to be far more accurate at detecting toxic chemicals than animal-based tests (83% accuracy vs. 59% accuracy).11, 12 Even despite there being many more similar findings 13, 14, in vitro testing is still criticized by the scientific community because it does not represent a whole body system, whereas animal experiments do. While in vitro testing can be simplistic, this argument can only be valid if there is already a method of accurately replicating whole human body systems. But, as explained above, the fact is that whole animal body systems simply do not reflect whole human body systems.
A similar concept to studying human cell cultures and expanding that to a whole body system is that of microdosing. Microdosing is used in drug development, where instead of studying the effects of the drug in animals, the drug is administered in tiny doses in human volunteers, and the cellular effects monitored. The dosage at which the drugs are administered are too low for toxic effects to occur at a system level, but large enough that effects on cells can be studied. Microdosing has been criticized for the same reasons as in vitro testing, but is also baseless for the same reasons too, especially as the methods used for replicating human systems in current drug development has a failure rate of 92-96%.
Similar to in vitro testing, studies are now being done on the effects of stimuli (mostly drugs) to specific human genes.15 The fact that this is possible at all is a credit to how far science has come, and continuing to use animal gene testing instead of transitioning to this current human gene technology is borderline scientifically negligent, and represents nothing more than a stubbornness to move with the times.
Possibly the most exciting development in alternatives to vivisection is organs-on-chips. These chips, the size of computer memory cards, are composed of human cells and designed to replicate human organs. If multiple organ systems can be replicated on chips, a whole body system can be developed to accurately predict human responses to drugs (for example).16 Organs-on-chips are often scorned by those who conduct animal experiments, but to anyone who has doubts please watch this video on the lung-on-a-chip the Wyss Institute at Harvard has designed and been able to achieve so far with it.
All these alternatives do not even touch on the other huge part of medical research separate to lab-based studies – clinical research. So much can be learned from simply observing a human population and the way they develop and respond to human diseases. This is a field of research called epidemiology, which has already been hugely influential in the understanding of public health and surrounding policy building that has developed from that.
Co-founder and Campaign Director, Animal Liberation Tasmania
- AKHTAR A. The Flaws and Human Harms of Animal Experimentation. Cambridge Quarterly of Healthcare Ethics. 2015; 24(04):[407-19 pp.].
- FDA. Innovation or Stagnation, Challenge and Opportunity on the Critical Path to New Medical Products Rockville. 2004.
- Pippin J. Animal research in medical sciences: Seeking a convergence of science, medicine, and animal law. South Texas Law Review. 2013; 54:[469-511 pp.].
- Schmidt C. Researchers Exploring Faster Alternatives to 2-Year Test for Carcinogenicity. Journal of the National Cancer Institute. 2006; 98(4):[228-30 pp.].
- Knight A, Bailey J, Balcombe J. Animal carcinogenicity studies: 1. Poor human predictivity. Alternatives to laboratory animals : ATLA. 2006; 34(1):[19-27 pp.].
- Heywood R. Target organ toxicity. Toxicology letters. 1981; 8(6):[349-58 pp.].
- Gori GB. The costly illusion of regulating unknowable risks. RTP. 2001; 34(3):[205-12 pp.].
- Fletcher AP. Drug safety tests and subsequent clinical experience. Journal of the Royal Society of Medicine. 1978; 71(9):[693-6 pp.].
- Bracken MB. Why animal studies are often poor predictors of human reactions to exposure. Journal of the Royal Society of Medicine. 2009;102(3):120-122.
- Oxford Centre for Animal Ethics. Normalising the Unthinkable: The Ethics of Using Animals in Research. 2015.
- Clemedson C, McFarlane-Abdulla M, FA A, al. e. MEIC evaluation of acute systemic toxicity. Part II. In vitro results from 68 toxicity assays used to test the first 30 reference chemicals and a comparative cytotoxicity analysis. ATLA. 1996; 24:[273-311 pp.].
- Clemedson C, Barile F, Chesne C, al. e. MEIC evaluation of acute systemic toxicity. Part VII. Prediction of human toxicity by results from testing of the first 30 reference chemicals with 27 further in vitro assay. ATLA. 2000; 28:[161-200 pp.].
- Voskoglou-Nomikos T, Pater JL, Seymour L. Clinical Predictive Value of the in Vitro Cell Line, Human Xenograft, and Mouse Allograft Preclinical Cancer Models. Clinical Cancer Research. 2003; 9(11):[4227-39 pp.].
- Mayor S. Researchers refine in vitro test that will reduce the risk of “first in humans” drug trials. BMJ. 2008; 337.
- Coghlan A. Pioneers cut out animal experiments. New Scientist. 1996.
- Bhatia S, Ingber D. Microfluidic organs-on-chips. Nature. 2014; 32(8):[760-72 pp.].