Biased Clinical Trial Results
[Posted on: Thursday, November 3, 2016]
Bias in clinical trial results is often suspected, particularly when the studies are not independently reviewed by regulators. Clinical studies are often conducted for marketing purposes with non-FDA regulated products such as food and supplements. In a review of clinical studies conducted to evaluate the link between consumption of soda and occurrence of obesity, it was found that all the studies funded by the soda manufacturers did not find any link between consumption of soda and obesity, while those that were not funded by the beverage industry found that consumption of high sugar soda lead to obesity. It is well known that consumption of more sugary products causes obesity, so it is surprising when studies find on the contrary. Of the 60 clinical studies to evaluate link between sugary beverages and obesity and diabetes over 15 years, all the 26 that were financially supported by the beverage industry found no link between soda and obesity. On the other hand, practically all the other 34 studies found that drinking soda lead to obesity. This raises an obvious doubt of bias. The beverage industry obviously does not agree with these findings. This kind of bias is found in other areas as well. Several recent reports have argued that vitamins and mineral supplements do not help in preventing diseases as claimed. Most trials with supplements rely on anecdotal data as well that often does not withstand unbiased clinical testing. One can argue if similar bias exists in regulated clinical trials. Recently, a lot has been made of FDA’s decisions to approve drugs with limited benefits due pressure from the sponsors and patients who had obvious bias. Some degree to bias can potentially exist in any trial but the checks and balances built in the clinical trial approval and review process assures that any bias will be transparent. It is due to that process that we are aware of the limitations of the data in the controversial FDA approval, be it for female libido drug or a drug for Duchenne Muscular Dystrophy. The entire clinical trial approval and review process is designed to control for bias. How the public perception of bias in clinical trials in omnipresent and leads to issues with recruitment and non-compliance and hence sponsors need to work hard to control the perceptions in trial. The new clinical trial transparency rules should help as well.