Drug companies were accused today of conning the public by hyping up patented medicines with little new to offer while downplaying their side-effects.
An estimated 85% of new drugs offer few if any new benefits while having the potential to cause serious harm due to toxicity or misuse, a study has concluded.
The author of the research delivered a damning attack on "Big Pharma" at a meeting of sociology experts in the US.
Professor Donald Light described the pharmaceutical industry as a "market for lemons" - one in which the seller knows much more than the buyer about the product, and takes advantage of this fact.
"Sometimes drug companies hide or downplay information about serious side-effects of new drugs and overstate the drugs' benefits," said Prof Light, a professor of comparative health policy at the University of Medicine and Dentistry in New Jersey, US.
"Then, they spend two to three times more on marketing than on research to persuade doctors to prescribe these new drugs. Doctors may get misleading information and then misinform patients about the risks of a new drug. It's really a two-tier market for lemons."
He alleged that the pharmaceutical industry owned companies in charge of drug testing and provided "firewalls" of legal protection behind which information about dangers or lack of effectiveness could be be hidden.
Companies were assisted by the "relatively low bar" for effectiveness that had to be crossed to get a new drug approved, he claimed.
Prof Light presented his paper, entitled "Pharmaceuticals: A Two-Tier Market for Producing 'Lemons' and Serious Harm" today at the American Sociological Association's annual meeting in Atlanta, Georgia.
The study includes data gathered from independent reviewers which suggest that 85% of new drugs provide few, if any, new benefits.
Yet toxic side effects and misuse of prescription drugs had made medicines a significant cause of death, said Prof Light.
The professor makes the same claims in a new book, The Risk of Prescription Drugs due to be published this autumn by Columbia University Press.
In both his paper and the book, he describes the "risk proliferation syndrome" involved in drug marketing. This is said to arise from maximising the number of patients exposed to the side effects of new drugs of dubious efficacy.
Hyping a drug began with clinical trials designed to minimise evidence of harm and published literature that emphasised its advantages, said Prof Light.
Building on this foundation, pharmaceutical companies staged massive campaigns to sell the product, when a controlled limited launch would allow evidence of its effects to be gathered, he argued.
Leading clinicians were recruited to try using the drug for conditions other than those for which it was approved, and to promote "off-label" or unapproved uses, Prof Light maintained.
Physicians inadvertently became "double agents" - promoters of the new drug, yet trusted stewards of patients' health.
When patients complain of adverse reactions, studies show that doctors are likely to discount or dismiss them, according to Prof Light.
He accused companies of conducting a "swamp the regulator" policy - bombarding the bodies that award drug licences with large numbers of "incomplete, partial, sub-standard clinical trials".
One study of 111 final applications for approval found that 42% were missing data from adequately randomised trials, 40% were supported by flawed testing of dosages, 39% lacked evidence of clinical efficacy, and 49% raised concerns about serious adverse side-effects, he said.
Recently, major reports had focused on "biased, poor trials" involving the diabetes drug Avandia and the antibody cancer drug Avastin.
Avandia has been linked to an increased risk of heart attacks, while controversy surrounds Avastin's effectiveness as a breast cancer treatment.
A US Food and Drink Administration expert panel has called on the agency to withdraw its licence allowing Avastin to be used for this purpose.
Companies control the generation of scientific knowledge and which findings will go to licensing authorities such as the FDA or be published, Prof Light argued.
"The result is that drugs get approved without anyone being able to know how effective they really are or how much serious harm they will cause," he said.
"A few basic changes could improve the quality of trials and evidence about the real risks and benefits of new drugs. We could also increase the percentage of new drugs that are really better for patients."
Prof Light highlighted the marketing of statin cholesterol-lowering drugs as a good example of pharma hype.
Company-supported clinical researchers and medical writers created a global market for controlling cholesterol with statins, he argued.
A complex set of relationships between heart disease and saturated fats and cholesterol had been converted into the simple message that "cholesterol kills".
Yet two major trials of statins found little evidence that the drugs reduce the risk of heart attacks. In contrast, they showed an increased total risk of harm to health and death from the drugs despite the lowering of cholesterol levels.
One major meta-analysis, which pooled the findings of a number of studies, found that "statins were not associated with reduction in the risk of all-cause mortality".
Another trial led by a statin manufacturer was stopped early so that adverse side-effects were not recorded.
Mental illness and diabetes were other areas where questionable use of drugs occurred, said Prof Light.
Selective serotonin reuptake inhibitor (SSRI) antidepressants became immensely popular despite evidence that they are little better than "dummy" placebos for most patients.
In his paper, Prof Light concluded: "The evidence here indicates that the two-tier market for prescription drugs is the largest and most dangerous market for lemons in modern society. Neither wars nor used car injuries come close.
"Current incentives for research produce a few that substantially improve patients' chances of getting better or avoiding death but a large number of barely innovative drugs each year. These new drugs of little benefit consume about four-fifths of all drug costs.
"The incentives and institutional practices around testing and regulatory review predictably result in approvals being based on trials so biased and poorly run that no one knows how much better or worse new drugs are."
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