Would drugs be safe for us without animal tests?


Would drugs be safe for us without first being tested on animals?


Actually, drugs would be safer than they are now if the animal testing phase was eliminated. Many studies have shown that animals predict correctly for humans only 5-25% of the time: far worse than tossing a coin!

When researchers administer potentially useful substances to animals, they get plenty of feedback on the substances' effectiveness in the species tested. However, results nearly always differ dramatically between species, and there are no reliable methods of predicting a human reaction.

Substances that could save many human lives are not approved because they are harmful to animals. And substances that are therapeutic in animals get approved, later harming and sometimes killing humans.

More than 10, 000 people are killed every year in the UK by side effects of prescription medicines - now the fourth biggest killer in the western world. The US figure is over 100, 000. Arthritis painkiller Vioxx, withdrawn in 2004, caused up to 320, 000 heart attacks and strokes - as many as 140, 000 of them fatal. Animal testing failed to predict these tragedies, which could have been reduced or prevented altogether by modern, human-based tests using DNA chips, human tissues and micro-dose studies where volunteers are monitored with PET and other scanners.

British company Pharmagene uses human tissue exclusively, with the philosophy "a flood of new data on human genetics is making drug research in animals redundant. If you have information on human genes, what's the point in going back to animals?"

Many of our most popular drugs can be quite detrimantal to animals. So there is justifiable concern that animal tests are preventing us from acquiring much-needed medications, as Professor Cohn Dollery stated:

"... for the great majority of disease entities, the animal models either do not exist or are really very poor. [We risk] overlooking useful drugs because they do not give a response to the animal models commonly used."[2]

92% of new drugs fail in clinical trials, after they have passed all the safety tests in animals. Many drugs that reach the market are later withdrawn or relabelled because of serious side effects. Reliance on animal data allows companies to avoid the expense of bigger and better clinical trials.

If we don't use animals, what will we use?

This statement falsely assumes that animal experiments have been responsible for medical advances in the past. However, the real benchmarks of medical progress have relied on the following non-animal methodologies, as will future developments.

* In vitro (test tube) research has been instrumental in many of the great discoveries - of antibiotics, for example, and the structure of DNA, as well as all the vaccines we have today, including polio and meningitis.

* Epidemiology (population research) revealed that folic acid deficiency causes birth defects, that smoking causes lung cancer and that lead damages children's brains.

* Post-mortem studies are responsible for much of our modern medical knowledge - including the repair of congenital heart defects in babies.

* Genetic research has elucidated how certain genes are responsible for some diseases. DNA chips allow doctors to prescribe the right drug for specific patients, thus reducing serious side effects of chemotherapy, for example.

* Clinical studies of patients have given us most of our current treatments and cures - including our treatments of lazy eye and the knowledge that HIV transmission from mother to baby can be prevented.

* Human tissue is vital in the study of human disease and drug testing - animal tissues differ in crucial ways.

* Computer modelling is now very sophisticated, with virtual human organs and virtual metabolism programmes which predict drug effects in humans far more accurately than animals can.

* Advances in technology are largely responsible for the high standard of medical care we receive today, including MRI and PET scanners, ultrasound, laser surgery, cochlear implants, laparascopic surgery, artificial organs, pacemakers and even surgery to correct spina bifida in the womb.

* Human stem cells have already treated children with leukaemia and promise to deliver great benefits in the future.

Technically humans are animals, so what's the big difference?

Whereas all animal cells have properties in common - a nucleus, mitochondria and so on - we now know that even smaller idiosyncrasies distinguish the way the cells of different species react to food, environment and medicines. Failed animal experimentation has irrevocably proven that tiny differences can prevent disease in one species or enable it in another. The smallest biological differences between humans and animals lead to lethal errors when applying animal data to humans. White blood cell surface receptors, for example, leave humans uniquely vulnerable to AIDS. Even the animal experimenters' bible, The Handbook of Laboratory Animal Science, states:

"It is impossible to give reliable general rules for the validity of extrapolation from one species to another. [This] can often only be verified after the first trials in the target species [humans]. Extrapolation from animal models. . . will always remain a matter of hindsight."[3]

What about the argument that animal experimentation is indispensable as our only model of intact metabolic systems?

This assertion suggests that in vitro research methodologies, though valuable, cannot predict what will happen in a whole living system, which is true. But history has proven that results in lab animals are even more inadequate - predicting results solely for the animal tested, not humans.

Given that metabolic processes differ greatly between species, information garnered in animal experiments has no predictive value and is wholly unscientific when applied to humans. Very often substances that have proven effective in animals demonstrate no curative value for humans, sometimes even causing harm.

By using in vitro research and new technology we can simulate the living intact human far better than a lab animal can. All drugs must eventually be tested on humans, and those humans are every bit the lab creatures that animals are. These "clinical phases" of drug testing, as they are called, submit human volunteers to what are at first very incremental dosages, monitor their reactions, and slowly increase dosage.

Clinical testing and subsequent non-animal methods, such as epidemiology and post-marketing drug surveillance, provide what lab animals cannot - 100% accurate measures of the human metabolic processes.

How can we know that medicines will not cause birth defects without testing them on animals?

The medical principle called Karnofsky's Law states that any substance can be teratogenic (cause birth defects) if given to the right species, at the right stage in development, and in the right dose. Common table salt or even water can be teratogenic to some species in certain circumstances! Therefore, science has already told us that any medication can cause birth defects in some creatures. [4]

In addition, agents that are teratogenic to some species may have little or no teratogenic affect in others.[5] Of 1, 200 chemicals that caused birth defects in animals, only 30 were proven to affect humans. [6] As the book, Chemically Induced Birth Defects records:

"In approximately 10 strains of rats, 15 strains of mice, 11 breeds of rabbits, 2 breeds of dogs, 3 strains of hamsters, 8 species of primates and in other such varied species as cats, armadillos, guinea pigs, swine and ferrets in which thalidomide has been tested, teratogenic effects have been induced only occasionally."[7]

Rats, popular lab animals, have been shown to get birth defects from almost every chemical that causes birth defects in humans. But they also get birth defects from hundreds of drugs that are safely used by humans! If chemicals that harm rat offspring do not cause birth defects in humans, the animal tests are meaningless and non-predictive.

So what is teratogenicity-testing in animals good for and why does it continue? As obstetrics professor Dr. D. F. Hawkins points out:

"The great majority of perinatel toxicological studies seems to be intended to convey medical and legal protection to the pharmaceutical houses and political protection to the official regulatory bodies, rather than produce information that might be of value in human therapeutics."[8]

As Karnofsky's Law postulates, researchers can eventually inflict birth defects on a species with substances that are teratogenic in humans. But to what purpose? Non-predictive animal experiments are of no human value. They only deplete valuable research funding that might otherwise be of true medical value.

Didn't the polio vaccine come from animal experimentation?

Animal experimentation actually delayed this much-needed vaccine throughout the first half of the 20th century.

When polio first appeared around 1835, it rapidly paralysed and killed its victims. In 1908, a virus was suspected and scientists began working on a vaccine. Note: In developing vaccines, it's crucial to determine how the infection enters the body. Luckily, pathologists discovered the polio virus in human intestines as early as 1912, suggesting entrance through the digestive tract.

Meanwhile, researchers successfully infected monkeys with polio. But because monkeys contract polio nasally rather than orally, this "triumph" only postponed the development of an effective vaccine for decades. Incredibly, the scientists working on the vaccine chose to ignore the human digestive data in favour of the monkey data!

It is true that a "vaccine" was derived from animal experimentation. But manufactured from monkey tissue, this "cure" resulted in six human deaths and 12 cases of paralysis.[9] It was abandoned. Further animal experimentation led to the development of a nasal treatment, which only caused permanent olfactory damage to the children tested. [10-11]

In 1941, Dr. Albert Sabin studied human autopsies to finally disprove the nasal theory. He found the virus confined to the gastrointestinal tract, as had been documented nearly 30 years earlier.

Sabin later denounced the monkey model blunder:

"... prevention was long delayed by the erroneous conception of the nature of the human disease based on misleading experimental models of the disease in monkeys."[12]

Finally, in 1949, Nobel Prize winner John Enders paved the way for a vaccine by growing the virus in tissue cultures.[13] Though the vaccine could have been produced from human tissue, convention prevailed and manufacturers opted to use monkey tissue instead. Containing the live virus, the animal-based vaccine infected 204 people with polio and resulted in 11 documented deaths. It also resulted in at least one virus (SV4O) jumping the species barrier and infecting humans.

Because of that, the polio vaccine is now grown in human diploid-cell culture rather than animal tissue.

Didn't penicillin come from animal experimentation?

Actually, it's a fact that animal tests significantly sidetracked development of this important drug. In 1929, Alexander Fleming observed penicillin as it killed bacteria in a Petri dish. Intrigued, he administered the compound to bacteria-infected rabbits, hoping it would do the same thing.

"And it almost didn't come at all."

Unfortunately, penicillin was ineffective against the rabbit's infection. Disappointed, Fleming set the drug aside for a decade, as the rabbits had "proved" the drug was useless as a systemic medication.

Years later, he administered the drug in desperation to a dying patient, for whom all other treatments were ineffectual. The penicillin performed a miracle, and the rest is history.

Fleming might have thrown penicillin away had he done his initial tests on guinea pigs or hamsters, as it would have killed those species. Fleming later admitted that misleading results from animal testing almost prevented discovery of the entire field of antibiotics.

Weren't lab animals responsible for the discovery of diabetes and development of insulin?

Pro-animal experiment contingencies always cite the development of insulin as support for continued animal testing, asserting that insulin harvested from slaughterhouses saved the lives of many diabetics. This is true. But the use of animals in the search for the cause of diabetes has been overwhelmingly counterproductive.

Diabetes affects in excess of 125 million people worldwide and is a leading cause of blindness, amputation, kidney failure and premature death. Physicians in the late 18th century first linked the disease with characteristic changes in the pancreas seen at autopsy. As this was difficult to reproduce in animals, many scientists disputed the pancreas' role in the disease. When they removed the pancreas from dogs, cats, and pigs, the animals became diabetic. But their symptoms led researchers to conjecture that diabetes was a liver disease, throwing diabetes research off track for decades. In 1922, outraged scientists spoke out against the animal experiments that many were claiming had proven the existence of insulin:

"The production of insulin originated in a wrongly conceived, wrongly conducted, and wrongly interpreted series of [animal] experiments."[14]

They pointed out that human autopsy had in fact shown the pancreas to be the vital organ in diabetes, and that in vitro research had isolated insulin - not animal experiments.

Scientists later modified the in vitro process they had used to isolate insulin, successfully mass-producing pig and cattle insulin reaped in slaughterhouses. This animal-derived insulin indeed saved lives, but not without complications. It also created allergic reactions and exposed patients to serious health risks. Had they recognised these dangers, scientists would have hastened to develop human insulin.

Insulin is only a treatment for diabetes, not a cure. The exact biochemical process through which insulin regulates blood sugar is yet to be discovered. If the funds devoted to studies had gone to human research, would we still have this plague?

RESULT: Lab animal tests threw diabetes research off track for decades.

How will we combat AIDS without animal experimentation?

Over the last 20 years, billions have been spent fruitlessly trying to infect animals with AIDS. Given the inability to produce an adequate animal model, it is foolish to assume that animal experimentation will lead us to a cure. Many in the AIDS community - with their lives on the line - actively demonstrate against animal experiments as a waste of precious time and money.[15]

Blood from those infected with HIV remains our most illuminating research material to date. Humans who do not progress from HIV to AIDS offer excellent insight to possible ways of countermanding the disease. [16]

Through epidemiology and in vitro research, scientists have already isolated the human gene believed responsible for their immunity.[17] Though proponents of animal testing claim AZT and other preventative medications for AIDS were developed through animal research, existing human data and computers were in fact responsible. [18]

AIDS kills humans at the cellular level, so that is where it needs to be studied. Mindlessly investing valuable research funding in animal experiments only keeps AIDS patients ill.[19-22]

Aidsvax was tested on 8, 000 high-risk volunteers because it protected chimpanzees from HIV infection. Unfortunately for the volunteers, it afforded them no protection whatsoever.

If not with animals, how can we ever hope to cure cancer?

Cancer has now overtaken heart disease as the number one killer in the UK. One major reason we have not yet stemmed mortality from cancer is this: animal cancer is not the same as human cancer.

Cancer is not one disease. It is many. In humans, there are over 200 different forms of cancer afflicting different organs, tissues, and cells. Though comparable animal organs, tissues, and cells may become cancerous, the cancers are never identical to human carcinomas.

Given substances are not necessarily carcinogenic to all species. Studies show that 46% of chemicals found to be carcinogenic in rats were not carcinogenic in mice. [23] If species as closely related as mice to rats do not even contract cancer similarly, it's not surprising that 19 out of 20 compounds that are safe for humans caused cancer in animals. [24]

The US National Cancer Institute treated mice growing 48 different "human" cancers with a dozen different drugs proven successful in humans, and in 30 of the cases, the drugs were useless in mice. Almost two-thirds of the mouse models were wrong. Animal experimentation is not scientific because it is not predictive.

The US National Cancer Institute also undertook a 25 year screening programme, testing 40, 000 plant species on animals for anti-tumour activity. Out of the outrageously expensive research, many positive results surfaced in animal models, but not a single benefit emerged for humans. As a result, the NCI now uses human cancer cells for cytotoxic screening.[25]

Dr. Richard Klausner, as director of the US National Cancer Institute, plainly states:

"The history of cancer research has been a history of curing cancer in the mouse... We have cured mice of cancer for decades - and it simply didn't work in humans."

Didn't all Nobel Prize winners in Medicine and Physiology experiment on animals?

Yes, most did. But it doesn't follow that the discoveries would not have occurred without animals. It only means that the market for lab animals was thriving and accessible.

From the second half of the 19th century onward, experimenting on animals became part of all medical curricula. Therefore researchers were obliged to perform animal experiments to earn their degrees.

In the instances wherein animals were used for the Nobel Prize-winning results, they were not necessary. Though animal tissue research was the convention, human tissue was available and more viable - as many Nobel Prize winners have since remarked.

The discovery of the DNA double helix, arguably the 20th Century's most important medical breakthrough, would have been impossible without the non-animal methods of technology and in vitro research.

Don't all doctors support the concept of animal experimentation?

We commissioned a survey of 500 General Practitioners, conducted by global market research organisation TNS Healthcare in 2004. The results revealed a staggering level of distrust in results obtained from animal experiments:

* 82% were concerned that animal data can be misleading when applied to humans

* only 21% would have more confidence in animal tests for new drugs than in a battery of human-based safety tests

* 83% would support an independent scientific evaluation of the clinical relevance of animal experimentation

Clearly, a silent majority of doctors today are aware that animal tests are not the safety net the public and the medical profession are frequently assured they are by the government and the pharmaceutical industry.

A paper published in the British Medical Journal on 28th February 2004 asked "Where is the evidence that animal research benefits humans?" If such evidence cannot be found, the practice should cease. Patients will benefit because they will no longer be damaged by misleading data, and also because the resources currently pouring into animal research will be freed for clinical research.

Today, medicine is much more evidence-based and it is time to weigh the real harm from animal experiments against the alleged benefits. An independent, transparent evaluation of the scientific value of animal experiments is long overdue. Incredibly, the government "has not commissioned or evaluated any formal research on the efficacy of animal experiments and has no plans to do so" (Home Office, April 2004).

Don't surgeons train on animals before operating on humans?

Many surgeons have done trial procedures on lab animals, but many others have admitted that working on animals confuses the issue. Common sense suggests that orthopaedic surgery on a dog, for example, will differ greatly from that on a human. Applying animal data to the human body is always unscientific. Here are some examples:

* Once ophthalmologists practiced radial keratotomy (corrective eye surgery) on rabbits, they later tried it out on humans. After blinding many individuals, doctors modified the procedure for the human eye. Had they originated their research on the human eye through in vitro or autopsy research, these tragedies would have been prevented.

* Extracranial-intracranial (EC-IC) bypass procedures for inoperable carotid artery disease were tested and perfected on dogs and rabbits. Once approved for humans, neurosurgeons performed thousands of EC-ICs before they discovered the operation caused death and strokes more often than it resulted in recovery.[27]

* Thousands of cats, dogs, pigs and primates have been sacrificed to find successful procedures for organ transplants. But despite the number of practice surgeries on animals, the first human operations fail.

By practicing procedures on non-humans, surgeons lead patients to believe their risk is minimal. Unfortunately, when a new method is introduced and tested on a human subject, projected results are no more than guesswork. By conducting the initial operations on human cadavers, doctors would reduce this risk and improve patient care.

How did animal experimentation become so established to begin with?

There have always existed abundant human bodies, tissue, and blood to augment our knowledge base. But when western Catholicism prevailed, papal decree forbade autopsy. In the second century AD, a Roman physician named Galen performed endless animal experiments and generated over 500 treatises on animal physiology.

Galen's false hypotheses - declaring that animals possess the same physiology as humans - helped dim the light throughout the Dark Ages, but the Renaissance offered a slight reprieve. When competitive intellectual inquiry overwhelmed Church injunctions, autopsies revealed animal-based inaccuracies and shed light on the true nature of human disease.

In the 1600's - 1800's, when so little was known about physiology, one could learn basic things from animals, because all mammals have things in common at the gross level: they all have hearts, lungs and livers, for example. Today, our studies are at the molecular level precisely where the differences between species are greatest. In the mid 19th century, Claude Bernard took up animal experimentation. His tremendous zeal and proliferation of data created a market for animal experimentation.

"From a history of misconceptions..."

In the 1930's, a disaster over ethylene glycol poisoning established animal testing as routine in drug development. The disaster of thalidomide, a drug for morning sickness that led to over 10, 000 babies with birth defects, spurred governments to mandate animal testing as a supposed guarantee of drug safety. Never mind that animal tests had failed to predict the thalidomide tragedy itself. [30]

Why does animal experimentation continue?

Many factors perpetuate animal experimentation, the most obvious of which is momentum. The tradition is so deeply ingrained that the whole system is based on it. Its fundamental acceptance has long allowed it to escape attention. Many doctors and scientists have now started to question it - as evidenced by our recent survey of GPs.

Another factor is that researchers are far removed from patient care and really believe that by experimenting on animals they are helping to cure human disease. Also, they attract grant money based on how many papers they publish in the scientific literature. It is much easier and faster to publish papers using animals than by doing human-based research.

There are many other reasons but by far the most important is money. Animal breeders and cage and equipment manufacturers are £ multi-billion industries. But the biggest beneficiary is the pharmaceutical industry. Animal tests help them speed new drugs to market and, most significantly, give them a legal defence against public allegations of inadequate safety testing.
Pharmaceutical companies have known for decades that animal testing is scientifically worthless but they use it to provide liability protection when their drugs kill or injure people. Juries are easily swayed by volumes of safety data from rats, mice, dogs and monkeys - even though it is meaningless for humans.

Sadly, nothing has really changed since Thalidomide. Vioxx (2004) was the biggest drug recall in history, leaving thousands of deaths in its wake. Richard Horton, editor of The Lancet, said: "This is a public health emergency which raises grievous questions about the adequacy of our regulatory system."


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