A new study finds that clinical trials funded by the pharmaceutical industry are more likely to report a positive outcome, but less likely to be published shortly after completion than trials funded by other sources, such as the federal government, non-profit groups or academia. Unlike previous studies on this topic, the researchers say their study broadens the debate because they made a point of examining 546 trials that were registered on ClinicalTrials.gov and involved five widely used classes of meds for treating depression, high cholesterol, high blood pressure, heartburn and schizophrenia.
All of the trials occurred between 2000 and 2006. The study, which was published in The Annals of Internal Medicine, found 346 trials, or 63 percent, were primarily funded by industry, 74 or 14 percent were funded by government sources, and 126 or 23 percent by non-profits or other organizations. The upshot: Industry-funded trials were more likely to be Phase III or IV trials (88.7 percent); to use an active comparator in controlled trials (36.8 percent); to be multicenter (89 precent) and to enroll more participants. Overall, 362 trials or 66.3 percent had published results.
Meanwhile, industry-funded trials reported positive outcomes in 85.4 precent of publications, compared with 50 percent for government-funded trials and 71.9 percent for non-profit and other trials funded by non-government organizations. Trials funded by non-profits and other groups with industry contributions were also more likely to report positive outcomes than those without industry funding - 85 percent versus 61.2 percent. The rate of publication within 24 months of completion ranged from 32.4 percent among industry-funded trials to 56.2 percent among nonprofit or nonfederal organization–funded trials without industry contributions (read the abstract).
"This raises concerns that the findings may, in part, be related to biases in trials – the design or the way they are reported to the public," Florence Bourgeois, a faculty member in the division of emergency medicine at Children's Hospital in Boston, and one of the researchers, tell us. "We don’t know for sure, it may be other things that could sway results. It could be the questions that investigators choose to ask or the type of patient selected or how long the patient population is followed. All of these may impact results.
"The findings raise questions about whether the system is providing sufficient oversight," she continues. "More oversight is needed and additional information is needed about the way the trials are designed. This would be critical in examining these factors. It would be helpful if study protocols were posted in ClinicalTrials.gov or comprehensive FDA review material of trials reviewed in the drug approval process for every medication were made available, although just providing study protocols may not be sufficient."
A PhRMA spokeswoman send us a statement which, in part, says the trade group is striving for greater transparency and notes that the study "demonstrates one more way that patients and the public health can benefit from increased transparency: The study would not have been possible without the large volume of information about ongoing and completed industry-sponsored clinical trials provided through ClinicalTrials.gov and supported by PhRMA and its member companies. “While our review of the study continues, it is important to note that the authors acknowledge that industry-funded trials tended to be for later stages in the lengthy drug development process. As the authors note, ‘Later-phase trials may be more likely to have positive outcomes, because there is more certainty about the drug’s efficacy and safety at this advanced stage in the drug-development cycle.’