The Use Of Non-human Primates In Medical Research

THE USE OF NON-HUMAN PRIMATES IN MEDICAL RESEARCH∗

Though not well known to the general public, the University of British Columbia (UBC) uses non-human primates in a variety of research projects. In a January, 2008 article in the UBYSSEY, the student newspaper wrote, “Most notable perhaps, has been the continued use at UBC of non-human primates in neurological experiments.Recently, the rhesus macaque, an Asian species, has been used extensively in Parkinson’s disease research. The monkeys are typically subjected to brain damage which models the degenerative disease and then treated with various methaphetamine and electroconvulsive shock therapies.”

But does research on non-human primates really work? Has using these animals actually contributed to medical advancements? A closer look at research on nonhuman primates shows such research is ineffective, misleading, and harms not only the animals but people too:

Drug testing – The major experimental use of primates is for safety testing of medicines. Yet primates’ track record at predicting drugs’ dangerous side effects is abysmal. Many drugs that were safe for primates have gone on to injure or kill people.

• Six young men nearly died at the Northwick Park Hospital in 2006 when they were given a new drug because it had been ‘proven safe’ in monkeys at high doses.

• Arthritis drug Vioxx, withdrawn in 2004, killed up to 140,000 people – the biggest drug disaster in history – after being ‘proved safe’ in monkeys.

• Hormone replacement therapy (HRT), given to millions of women on the basis of research in monkeys, has been found to increase rather than decrease the risk of heart disease and stroke, as well as breast and ovarian cancer. HRT (labeled ‘the new thalidomide’ by the German Commission on the Safety of Medicines) caused 20,000 cases of breast cancer in Britain in one decade plus 1,300 cases of ovarian cancer since 1991, according to The Lancet, the world’s leading general medical journal and specialty journals in Oncology, Neurology and Infectious Diseases.

• Isoprenaline killed 3,500 young British asthmatics in the 1960s. Retrospective attempts to induce similar effects in primates and other animals failed.

Brain research – The second major use of primates is for brain research. Yet, the most dramatic differences between humans and other primates are in the brain.

• Human brains can now be studied non-invasively using remarkable high-tech scanners. These enable the conscious brain to be observed while engaged in a variety of cognitive tasks of which monkeys are not even capable.

• Alzheimer’s – Using primates has failed to inform the medical community about Alzheimer’s disease pathology. Plaques and tangles in the brain are the hallmark of Alzheimer’s disease in humans, but not in monkeys. Human and in vitro studies produced the genetic, biochemical, and lifestyle information and hypotheses that are elucidating the disease. An Alzheimer’s “vaccine”—AN-1792—was well tolerated in monkeys, but caused strokes and inflammation of the central nervous system in humans.

• Parkinson’s – Fundamental differences in the symptoms and pathology of Parkinson’s disease exist between primates and humans. Major breakthroughs arose through epidemiology, clinical studies, genetic research, human tissue studies, and autopsies.

• Stroke – Primates have artificially modeled strokes for decades, despite critical physiological differences. Significant species and strain-specific differences exist. Hundreds of drugs for stroke have been developed and tested in primates and other animals, yet all of them have failed and even harmed patients in trials.

Infectious disease research – Even chimpanzees, our closest living relative, are immune to the human AIDS virus, Hepatitis B and C, malaria and many other serious human pathogens. It is futile to study infections in animals that do not contract them in any similar way.

• The US government redirected $10 million of AIDS research funding away from chimpanzee studies after concluding they are a “deficient model.”

• Eighty AIDS vaccines have failed in human trials following success in primates.

• In the French blood scandal in the 1980s, thousands of people contracted HIV through contaminated blood – given to patients because it was safe in chimps.

• The polio vaccine was delayed for decades by “the erroneous conception of the nature of the human disease based on misleading experimental models of the disease in monkeys” according to Albert Sabin MD, the vaccine’s inventor.

What a difference some genes make
Non-human primate experiments confound medical research because of fundamental genetic and biochemical differences between humans and non-human primates:

• Human genes confer greater susceptibility to age-related neurodegenerative diseases such as Alzheimer’s and Parkinson’s.

• In chimpanzees, 20 out of 333 genes implicated in human cancer are different; 560 genes show differences that can affect the immune system; 169 genes in the cerebral cortex are expressed differently; and in the prefrontal cortex, 965 genes are expressed in humans but not chimps, and 344 in chimps but not humans. Of genes commonly expressed in the two species, 20 percent have a different expression profile, of which 52 genes are linked to neurological diseases.

• Eighty percent of proteins are different to some degree in chimpanzees compared with humans.

Putting an end to research on non-human primates will help animals and people
Ending non-human primate research would benefit human medicine by halting the flow of unreliable data from it, and by diverting research funds to more appropriate and promising methods. These include batteries of human-based tests that provide reliable and relevant information on which to base further research and translate laboratory findings to the clinic: microarrays and other DNA technologies; proteomics and metabolomics; mathematical and computer modelling; epidemiology; human clinical research; myriad in vitro molecular biological techniques; microfluidics devices; scanning technologies, microdosing – technologies that have demonstrably contributed to human medicine.


∗Information compiled from the Safer Medicines Campaign and Physicians Committee for Responsible Medicine. For
more information go to: http://www.curedisease.net/index.shtml and http://pcrm.org/