Researchers at Children's Hospital Boston (MA, USA), the Harvard-MIT Division of Health Sciences and Technology (Boston, MA, USA) and other institutions conducted a study to describe the characteristics of drug trials listed in ClinicalTrials.gov (clinicaltrials.gov)--a web-based registry of clinical trials launched in 1999--to examine whether the funding source of these trials was associated with favorable published outcomes. To do so, they conducted an observational study of safety and efficacy trials for anticholesteremics, antidepressants, antipsychotics, proton-pump inhibitors, and vasodilators conducted between 2000 and 2006; publications resulting from the trials were then identified, and data were abstracted on the trial record and publication, including timing of registration, elements of the study design, funding source, publication date, and study outcomes. Assessments were based on the primary funding categories of industry, government agencies, and nonprofit or nonfederal organizations.

The results showed that among 546 drug trials, 346 (63%) were primarily funded by industry, 74 (14%) by government sources, and 126 (23%) by nonprofit or nonfederal organizations. The researchers found that industry-funded trials reported positive outcomes in 85.4% of publications, compared with 50% for government-funded trials and 71.9% for nonprofit or nonfederal organization-funded trials. Trials funded by nonprofit or nonfederal sources with industry contributions were also more likely to report positive outcomes than those without industry funding. The researchers also found that industry-funded trials were in more advanced phases of study; 89% were Phase 3 or Phase 4, versus just 51% of government-funded trials and 65% of nonprofit or nonfederally funded trials. However, even Phase 1 and 2 trials funded by industry reported the highest percentage of favorable outcomes. The study was published in the August 3, 2010, issue of the Annals of Internal Medicine.

"Industry is very good at knowing what they want to study, and industry-sponsored studies are more efficient and well funded; but despite these potential biases, this is a stunning result,” said lead author Florence Bourgeois, M.D., M.P.H, of Children's Hospital Boston. "While we cannot specifically point to which factors contribute to the association between funding source and positive result reporting, our findings speak to the need for more disclosure of all elements of a study. Publication bias is likely a contributing factor, but there may be many more, including biases in study design, patient selection, data analysis, and results reporting.”

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Children's Hospital Boston
Harvard-MIT Division of Health Sciences and Technology