Drug Trials Funded By Manufacturers Find 50 Percent Greater Drug Effectiveness

October 12. 2024 by Huey Freeman

Authored by Huey Freeman via The Epoch Times

Drug studies sponsored by drug manufacturers tend to report higher drug efficacy than studies not sponsored by the drug company, a new report published in the Journal of Political Economy on Oct. 7 finds.

The report found a “sponsorship effect” that tends to bias sponsored studies toward reporting higher drug efficacies. The author could not find differences in study design between those funded by drug companies and those not.

“Removing the sponsorship effect would reduce the difference in efficacy ... by about 50%,” Tamar Oostrom, an assistant professor of economics at Ohio State University, said in her paper.

“This effect was larger than I expected,” Oostrom told The Epoch Times over email. “My results suggest that sponsored arms of trials should be discounted substantially.”

She said that the difference in results between sponsored and unsponsored trials may be that “manufacturers are running multiple trials and selectively publishing those that are more favorable towards their drug.”

Even a small effect of bias by funding could affect the use of a drug, she noted.

“If some of the results from a clinical trial are biased, patients may be taking a less effective drug for them, or they may be taking a drug when alternate treatment might be more beneficial,” Oostrom said.

Her research analyzed the published papers of 509 trials and 1,215 treatment arms (groups of participants). Most of the trials were published after the drug gained approval from the U.S. Food and Drug Administration (FDA). About three-quarters of them examined were for antidepressants, with the remaining quarter for antipsychotic medications.

“My paper is the first to examine the effect of financial sponsorship on outcomes by directly comparing a large set of trials in which the exact same arms are tested with differing financial interests,” Oostrom said.

Trials Comparing Drugs Vary by Funding

Oostrom examined two main types of drug trials: drugs that are compared to placebos and drugs that are compared to other drugs.

She found that the effect of drug company sponsorship was more pronounced in placebo trials.

There are multiple payoffs for results that favor a drug’s efficiency.

“Trials in which the manufacturer’s drug appears more effective are more likely to be published,” Oostrom said.

These published trials can be used in marketing to physicians. Prescriptions also tend to increase in response to favorable clinical trials.

Oostrom cited a 2023 study that found that when a clinical trial significantly favors a drug, “there is a large and immediate increase in demand.”

The trials Oostrom reviewed included an average of 100 participants, with a mean age of 42. Sex distribution was nearly equal, with 51 percent of participants being female.

Case Study: Effexor Versus Prozac

As an example of bias, Oostrom presented the case of Effexor, an antidepressant introduced by Wyeth Pharmaceuticals in 1993. Over the following 15 years, Wyeth funded 14 randomized controlled trials comparing Effexor’s effectiveness to its rival, Prozac. In 12 of these trials, funded solely by Wyeth, Effexor was found to be more effective.

However, when Effexor and Prozac were compared with alternative funding, only one out of three trials found Effexor to be more effective.

“Each of these trials is a double-blind RCT comparing the exact same two molecules and examining the same standard outcomes,” Oostrom wrote in her paper.

Expert Opinions on Research Bias

The study confirms that the funding of studies greatly influences their design and results, Dr. Chad Savage, an internal medicine specialist and founder of YourChoice Direct Care, told The Epoch Times.

“Multiple attempts have been made over the years to counter this effect, such as requiring financial disclosures from authors, but none have succeeded in fully eradicating the bias that can exist,” Savage said.

This bias often stems from the “self-preservation instincts of researchers, who are in a constant quest for funding” or possibly facing unemployment, he added.

“Solving this problem is challenging,” he said. “One potential solution is to return to the principle of reproducibility, a cornerstone of science. If a finding is valid, it should be replicable through multiple studies conducted by different researchers, with diverse funding sources, and published in different journals.”

According to Dr. Peter C. Gøtzsche, professor of clinical research design and analysis at the University of Copenhagen, the bias in industry-sponsored trials is massive.

“In head-to-head trials where Prozac was the drug of interest, significantly more patients improved on Prozac than in trials where Prozac was the comparator drug,” Gøtzsche told The Epoch Times.

He cited a 2004 study that found systematic bias in rating the effectiveness of Prozac, one of the first antidepressants on the market. Prozac is the brand name for fluoxetine.

The Epoch Times reached out to Eli Lilly, Prozac’s manufacturer, and Pfizer, which now owns Effexor, for comments.