Animal experimentation: a sight for sore eyes
By Paul Breschuk
Features
Editor
March 29, 2011
 As evidenced in last week’s article, roughly nine out of 10 drugs that pass the animal tests fail in human trials. Not only do these failures prove the animal tests useless, they have also injured and killed volunteers of the human tests.
Occasionally, however, drug makers find a successful, correlating crossover of data from animal to human trials. But even in these circumstances, researchers have likened the process to an event of sheer chance.
Even in an acceptance speech for his famous pharmacology work, Dr. B. B. Brodie said it is “a matter of pure luck that animal experiments lead to clinically useful drugs.”
Are the lopsided odds of such a coin toss good enough for researchers to breed, house, and experiment on over 100 million animals every year? What is the real reason for its continued practice, given animal experimentation’s extreme lack of usefulness in drug development?
Dr. James Gallagher gave us the answer way back in 1964. When he was then Director of Medical research at Lederle Laboratories, he confessed that pharmaceutical companies had an unscientific preoccupation with animal studies. “Animal studies are done for legal reasons and not for scientific reasons,” said Dr. Gallagher.
As with most industries, protection from litigation is of prime importance. Animal drug experimentation, then, can be seen as a means for paying lip service to public safety agencies. Whether or not the experimentation is effective, it provides evidence that at least some safety measures were taken. It gets drugs onto the market, which is all that really matters for pharmaceutical companies.
The failure to correlate data from animal to human drug trials is suggestive of a fundamental incomparability between different sets of species. This, of course, contradicts what we have long been told about both the physiological similarities between mice and humans and its overall usefulness as an analytical model.
So is rodent experimentation even relevant to humans, beyond its helpfulness to drug companies as a safeguard against litigation? Surely, there have been cases where the animal model offered useful applications for humans. But if the two species were really comparable, we would have already found a cure for cancer.
Dr. Richard Klausner, director of the U.S. National Cancer Institute, once reiterated this point, saying, “the history of cancer research has been a history of curing cancer in the mouse.”
Animal use is claimed to be an essential component of cancer research, with scientists searching for both cancer-causing and cancer-curing chemicals. But after decades of successfully dealing with cancer in mice, nothing from their findings can be applied to humans.
Simply put, the great majority of human carcinogens pose no risk to animals. Experiments using the standard National Cancer Institute Protocol, for example, found that 12 of the 19 chemicals known to cause oral cancer in humans were actually safe for animals. In fact, none of the most potent carcinogens for humans have ever been shown to produce cancer in monkeys. Even cigarette smoke was proven safe for the lucky monkeys of an Oregon Health and Science University study.
And, of course, the reverse is also true. Out of 20 compounds that do not cause cancer in humans, 19 were found to cause cancer in animals.
Other diseases show a similar incomparability between animal and human physiology. Approximately 700 drugs for the treatment of strokes have been found to work safely in animals. But of the 150 drugs tried so in human trials, not a single one has been found to be safe or effective. Likewise, 30 AIDS vaccines have failed in human trials after successful tests with primates.
Thankfully, alternatives to animal experimentation have been showing an increasing usefulness. Advocacy groups such as FRAME (Fund for the Replacement of Animals in Medical Experiments) believe in a slow but steady shift toward alternative research methods.
“Our long-term goal is the total elimination of laboratory animal use through the development, validation, and acceptance of replacement alternative methods,” reads the FRAME website. “Until this goal is reached, we also support efforts to reduce the numbers of animals used through better science and better experimental design, and to refine procedures so that the suffering of any animals necessarily used is minimized.”
Using the three Rs (refinement, reduction, and replacement), FRAME realizes that a wholesale switch from animal experimentation cannot happen overnight. It will take a slow shift, with both animal and alternative experimentation occurring side by side.
Techniques now available for researches include computer modeling, cell culture, microdosing, proteomics, and brain research.
One of the most promising alternatives is the Hurel chip, a microchip-like wafer lined with skin, lung, liver, and heart cells. Researchers can test the mammalian reaction to drugs by inserting small doses into each chamber, charting how each different tissue react.
“The entire experiment can be done very quickly,” said Dr. Chandna, a senior researcher for PETA. “You do not have to wait for the animal system to slowly deal with the drug, waiting weeks to see what happens. This alternative is faster, cheaper, and is more effective.” And more importantly, it does no harm to animals.
With these options, in addition to growing public concerns about animal experimentation, many companies have reduced their use of animal experiments by as much as 80 to 90 per cent. Some have even completely eliminated the practice.
Animal rights groups such as PETA and the Human Society have also made an impact on how ethical standards are enforced in laboratories. In just the last month, the Physicians Committee for Responsible Medicine persuaded NASA to cancel its cruel and unnecessary monkey radiation experiments.
Dr. Chandna believes the real challenge is getting animal experimentation out of university campuses. Although progress is being made, it is a slower process.
“There is a whole culture in academia where people come up doing their graduate studies using animals. Their whole careers in academia are mapped out using certain animal models, and doing certain types of research. It is a harder divestment,” said Dr. Chanda.
But there is also another, broader trend of mistreatment that reaches far back in our history. For example, the Tuskegee syphilis experiment of 1932 to 1972, using African Americans as guinea pigs, stemmed from the racist belief that African Americans are not fully human. This was pushed to the extreme with the many horrific experiments conducted by NAZI doctors on concentration camp prisoners. These disturbing abuses of the Hippocratic Oath were all done in the name of science, for the supposed betterment of one section of humanity.
“It is a mentality of oppression. It is what has historically allowed us to oppress other beings,” said Dr. Chanda. “That mentality is something that all too easily comes to the fore. And it is a scary thing.”
|
