When it comes to the influence that drugmakers can exert on clinical research, it's hard to surprise us anymore.
Published studies funded by drugmakers tend to have rosier outcomes than those paid for by the government and nonprofits.
Published studies funded by drugmakers tend to have rosier outcomes than those paid for by the government and nonprofits. iStockphoto.com
But we did take note this week of a pretty comprehensive analysis of how the handling of results from drug studies varies by who provided the money for the research.
For trials whose results get published (about two-thirds of the studied sample), roughly 85 percent of those financed by drug companies reported positive outcomes. When the government's bankrolling the work, only half the published results are positive.
Also, results of studies funded by drugmakers were less likely to be published within two years than those that had different funding sources.
The discrepancies "certainly does raise an alarm," says Dr. Kenneth Mandl, one of the study’s authors at Children's Hospital Boston. The results were published in the Annals of Internal Medicine.
Mandl tells Shots that his team looked at a range of studies for generic and brand-name drugs, including common medications for high cholesterol, depression and heartburn.
In all, they pored over almost 550 drug trials, listed on ClinicalTrials.gov between 2000 and 2006. Major journals require researchers to register drug trials on the website before publication.
It's not clear if drug companies are good at picking successful drugs or if they’re designing biased trials, says Mandl.
Drugmakers say there are reasons for some of the differences. "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," said a statement from PhRMA, a trade group for brand-name drugmakers. And those tests could be more likely to produce positive results.
But the study authors say funding source seemed to make a difference even after they adjusted for which clinical phase a drug was in.
The bottom line is there needs to be more oversight, said lead author Dr. Florence Bourgeois. Easy public access to details for trials of every drug would also help.