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Animal studies 'of limited use'
Mice are commonly used for research into human conditions Tests of drugs on animals are not reliable in all cases, a study warns.
The British Medical Journal research looked at studies in six areas and found animal studies agreed with human trials in just three.
The high-profile London drug trial which left six men ill was carried out after animal studies showed the drug TGN1412 was effective.
This study, led by Professor Ian Roberts, suggests animal studies should be used, but not for all drug research.
At the moment there is too much emotion and not much science
Professor Ian Roberts
Six men suffered serious organ failure early this year after taking part in a trial of the TGN1412 drug made by TeGenero.
In this study, a team from the London School of Hygiene and Tropical Medicine reviewed evidence from a wide range of human and animal trials looking at six areas of treatment.
They were using corticosteroids to treat head injuries and respiratory illnesses in babies, antifibrinolytics to treat bleeding, thrombolysis and tirilazad for stroke and bisphosphonates for osteoporosis.
But there was no consistent agreement between the animal and human studies.
Corticosteroids did not show any benefit for treating head injury in clinical trials but had done so in animal models.
Different results were also seen for tirilazad. Data from animal studies suggested a benefit but the human trials showed no benefit, and possible harm.
However, 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.
'Hysterical'
Professor Roberts said: "This is all about the predictive value of animal experiments.
"The debate over this issue is really quite hysterical. At the moment, there is too much emotion and not much science.
"Anti-vivisectionists say animal testing is of no use at all, and those who do them say we would have no safe and effective treatments if we didn't."
He said his investigations showed some animal studies were poorly carried out, involving too few animals and that they could be affected by design or publication bias.
Professor Roberts said animal experiments could be designed to better reflect human experience, and that there would be some areas of drug research where animal testing was relevant, and some where it was not.
"It could be that, as with the TeGenero drugs, because of the mechanism and the action, animal tests don't tell you very much about safety in humans; but others where having the right model in animals would help."
This is a step in the right direction in terms of public debate. Parliament determined that it is important to reduce the number of animal experiments, and it's clear that there's division amongst scientists as to how useful they actually are under what circumstances, with opinions falling right along the spectrum. But the public debate has been somewhat less than nuanced. I'm not convinced that animal experiments are the way to go, but an intelligent, nuanced public debate has to be better than the slanging match going on at the moment with the polar opposite camps simply calling each other names. If we want people to be convinced that modern technology makes animal experimentation obsolete, a nuanced public debate has to be in our favour.