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Just How Useful Are Animal Studies To Human Health?:

Animal studies are of limited usefulness to human health because they are of poor quality and their results often conflict with human trials, argue researchers in a study online in the British Medical Journal.

Before clinical trials are carried out, the safety and effectiveness of new drugs are usually tested in animal models. Some believe, however, that the results from animal trials are not applicable to humans because of biological differences between the species.

So researchers compared treatment effects in animal models with human clinical trials.

They used systematic reviews (impartial summaries of evidence from many different studies) of human and animal trials to analyse the effects of six drugs for conditions such as head injury, stroke and osteoporosis.

Agreement between human and animal studies varied. For example, corticosteroids did not show any benefit for treating head injury in clinical trials but did show a benefit in animal models. Results also differed for the drug tirilazad to treat stroke – data from animal studies suggested a benefit but the clinical trials showed no benefit and possible harm.

Some results did agree. For instance, bisphosphonates increased bone mineral density in both clinical trials and animal studies, while corticosteroids reduced neonatal respiratory distress syndrome in animal studies and in clinical trials, although the data were sparse.

Animal studies are generally of poor quality and lack agreement with clinical trials, which limits their usefulness to human health, say the authors. This discordance may be due to bias, random error, or the failure of animal models to adequately represent clinical disease.

Systematic reviews could help translate research findings from animals to humans. They could also promote closer collaboration between the research communities and encourage an interative approach to improving the relevance of animal models to clinical trial design, they conclude.

First of all, it’s not just efficacy of drugs that is tested in animals but also – and more importantly – safety. If a drug kills all the mice, it will never be tested in humans in the first place.

How about animal studies in the research in basic biology: evolution, ecology, behavior, physiology, cell biology, developmental biology, genetics….? So what if those studies are never even done in humans. We are, after all, just one species out of millions, and a lousy lab animal to boot. Yet, those kinds of animal studies teach us basic biology that subsequently give us ideas for further studies of medical treatments.

Comments

  1. #1 quitter
    December 18, 2006

    Exactly right, this kind of crap always undersells or dismisses the importance of basic science with animal research. We’d never get anywhere in science without the basic stuff, and people think the only thing scientists do is immediately applicable to clinical medicine when that’s like the top 5% of the pyramid. Further, toxicities are going to overlap a huge percentage of the time. It’s rare, not impossible since I know of at least one study that showed an odd toxicity of a drug in humans long term but not in rodents, but still rare for a poison to be completely species-specific.

    I also was privy to a very interesting result this week, not published any time soon, having to do with some amazing work in organ transplantation in humans that has a real revolutionary potential. It was completely a result of working out the details in animal transplantation models. When you are in science long enough you start to see these things that started out as maybe just a cell culture result, or an interesting protein isolated from some species of animal that ultimately becomes some great drug target or biomarker. I worry that over-interpreting crap like this will seriously hamper really important basic science research because people just have no idea about how science builds from simple to complex.

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