Thursday February 5, 2015
The following was submitted to the Baltimore Sun as an op-ed in response to an op-ed by Frankie Trull president of the Foundation for Biomedical Research, located in Washington, DC. As it was rejected I am posting it here. References were not included as it was for a newspaper. The references are present in our articles and books.
Animal models belong in the 19th century
In her op-ed of January 30, “Look to animals to cure Ebola,” Frankie L Trull presented a picture of animal-based research that is a far cry from reality. While animals and humans share many anatomical and physiologic traits, very small differences make animals unreliable models for human response to drugs and disease. For example, humans die from HIV/AIDS while chimpanzees merely contract a cold-like illness. Research with chimpanzees and other nonhuman primates have misled scientists and resulted in human deaths in HIV vaccine trials. There is no effective vaccine against HIV/AIDS despite scores of successes in nonhuman primates. The advances against HIV/AIDS have come from human-based research.
Sharing 98% of our genes with chimpanzees is not sufficient in terms of relying on them to predict human response to drugs and disease. Monozygotic twins share essentially 100% of their genes yet one might develop a disease like schizophrenia while the other will not. If identical twins do not always respond the same way to drugs and disease, the notion that animals, be they 92% or 98% genetically similar, will be of predictive value for humans is absurd.
The Nuremberg Code and other guidelines for conducting ethical research do mandate animal-based research and testing. However, these rules were made before the discovery of the double helix of DNA and before science revealed the genetic differences between individuals of the same species, not to mention the greater genetic differences among species. Science has proven that using one species in hopes of predicting the response of a second to drugs and disease is futile. Animal models have a predictive value approximately equal to a coin toss in such matters. The ethical guideline need to modernized. I have addressed this in the medical journal BMC Medical Ethics.
History also supports this position. Animal models delayed the polio vaccine for decades because of small differences among species. Anesthesiologists avoided administering phenylephrine to women in labor based on dog studies only to learn decades later that phenylephrine is actually the drug of choice for treating low blood pressure in these circumstances. Again based on studies in dogs, the general anesthetic isoflurane was considered unsafe for patients with heart disease and was thus avoided when in fact it appears to have protective properties for the heart. Smoking and asbestos were deemed safe for humans based on studies in animals. Such examples are easily multiplied.
Currently, a vast majority of drugs that pass animal tests for safety and efficacy fail when given to humans. Occasionally an animal model will react the same as humans but this is meaningless since scientists have no way to know in advance which animal models is similar to humans in this single situation. Unless the animal model has a high predictive value—many drugs have been tested and the animal model responds the same as humans—such coincidence are of no value scientifically.
Finally, society has better options. Human-based research in the form of linking genes to disease and drug response is transforming the way medicine is practiced. Personalized medicine is not just hope for the future; it is the way medicine is being practiced today in many cases. Most physicians assert that advances in technology, which came about as a result of basic research in fields like chemistry and physics, have contributed more to the improvement of medical care than anything else in the last 50 years. Combining technology and human-based medical research has given us genes on a chip that will allow physicians to test a new drug on your genes. This is vastly different from testing drugs on animals and hoping for the best.
Because we have used animals for so long, many in society have trouble believing the practice is of so little value. But such is the history of science. Many practices and beliefs have been falsified by science. People of past generations had just as much trouble accepting a round earth or the fact that physicians should wash their hands before seeing patients as we have today of acknowledging that animal models should be assigned to the trash bin of history. In addition, today there is a large group of people whose incomes, careers and egos are centered on the outdated notion that animals are just funny-looking humans. Very large sums of money are involved and these people have their own lobbyists on Capitol Hill.
Knowledge is power. Familiarize yourself with all the relevant facts before believing what anyone says about this or any other topic.