Research funded by drug companies is more likely to produce results that favour the sponsor鈥檚 product, reveals a new study.
Researchers analysed 30 previous reports examining pharmaceutical industry-backed research and found the conclusions of such research were four times more likely to be positive than research backed by other sponsors.
鈥淲hat we found was that in almost all cases there was a bias 鈥 a rather heavy bias 鈥 in favour [of a drug] when the study was industry funded,鈥 study leader Joel Lexchin told New 杏吧原创.
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The main reasons for this, say the team, may be that positive studies are more likely to be published than negative ones. Also, inappropriate comparison drugs may be used in these trials, skewing findings in favour of the tested product.
The new analysis is published in a special issue of the British Medical Journal, which focuses on the close relationship between doctors and the pharmaceutical industry.
Two to entangle
鈥淒octors, drug companies and most importantly patients would all benefit from greater distance,鈥 cautions BMJ editor Richard Smith. 鈥淚t does of course take two to entangle, and we hope that nobody will see this theme issue as anti-drug company.鈥
But Richard Ley, a spokesman for the Association of the British Pharmaceutical Industry, rejects the study鈥檚 findings. 鈥淭he average drug takes 10 to 12 years to develop and costs 拢350 million 鈥 even if you are the most selfish company in the world you can鈥檛 afford to risk the time and money [to produce biased results],鈥 he told New 杏吧原创.
The clinical trials are overseen from start to finish by independent ethics committees, says Ley, with final checks made by a country鈥檚 licensing authorities.
Quality scale
Lexchin, an expert in pharmaceutical policy, at York University in Toronto, Canada, and colleagues analysed 30 studies examining drug-industry backed trials between 1966 to 2002.
Industry sponsored studies were less likely to be published than research funded by other sources. However, drug company backed studies were four times more likely to show favourable results than studies funded by other sponsors.
But of the 13 studies that looked at the scientific methods used, none reported that the industry-backed trials were of lower quality. Lexchin says this is because standard scales used to examine scientific quality do not cover all issues, such as what drug was used in a trial as a comparison.
Industry-backed studies often compare a new drug to placebo or a second line agent, he says, which makes it easier to get a positive result for a new drug. 鈥淢y preference would be to compare with what鈥檚 recommended as the current best therapy,鈥 he says.
Lexchin notes that in Canada and the US, the pharmaceutical industry is the largest funder of medical research. 鈥淚t does have implications in terms of whether or not we can believe the results of research they are funding鈥 he says. 鈥淚 certainly hope we can, but our study raises questions.鈥