Design flaws plague many animal-based drug studies, researchers say

January 22, 2014
Design flaws plague many animal-based drug studies, researchers say
They include poorly organized trials and no follow-up on side effects from the medicines tested.

(HealthDay)—Many pharmaceutical studies in animals that lead to trials in humans have serious design flaws, a new study suggests.

Researchers analyzed 63 animal studies of popular cholesterol-lowering drugs called statins—drugs such as Crestor, Lipitor and Zocor. Some of the studies were funded by the government and other non-industry sources, while others were paid for by drug companies.

Numerous were found in the studies regardless of who funded them, found the researchers, led by Lisa Bero, a pharmacologist at the University of California, San Francisco, School of Pharmacy.

For example, were not randomly divided into treatment or placebo groups—a requirement of high-quality clinical trials—in about half the studies, the researchers said.

And in about half the studies, the animals were identifiable to the person giving them the drug or placebo, Bero's team found. That's a violation of a research practice called "blinding," in which researchers do not know which animal or human got the treatment and which did not.

In addition, many of the studies did not explain the criteria for including or excluding animals, the researchers said. Many also did not properly explain treatment changes made among groups of animals that were being given the drugs.

Finally, the harmful side effects—the "adverse events"—of the drugs were not investigated.

"Not a single animal study we looked at assessed adverse events following the statin intervention," Bero said in a university news release.

"As toxicity data from animal studies must be submitted to regulatory authorities before a compound can proceed to testing in humans, it is surprising that so little data on harm appears in the published scientific literature," she said.

Conclusions of all the studies tended to be favorable, the researchers said. But compared to studies funded by government and other nonindustry sources, studies funded by were more likely to present favorable conclusions—even when the data was less favorable.

These findings highlights the role of "spin" in communicating study findings, Bero said.

The study was published online Jan. 21 in the journal PLoS Biology.

Explore further: Bias pervades the scientific reporting of animal studies

More information: The U.S. Food and Drug Administration explains how drugs are developed and approved.

Related Stories

Bias pervades the scientific reporting of animal studies

July 17, 2013

A new study published in the open access journal PLOS Biology suggests that the scientific literature could be compromised by substantial bias in the reporting of animal studies, and may be giving a misleading picture of ...

Study examines drug labeling and exposure in infants

December 9, 2013

Federal legislation encouraging the study of drugs in pediatric patients has resulted in very few labeling changes that include new infant information, according to a study by Matthew M. Laughon, M.D., M.P.H., of the University ...

Recommended for you

Researchers identify source of opioids' side effects

January 17, 2017

A commercially available drug may help drastically reduce two side effects of opioid painkillers—a growing tolerance and a paradoxical increased sensitivity to pain—without affecting the drugs' ability to reduce pain, ...

CVS generic competitor to EpiPen, sold at a 6th the price

January 12, 2017

CVS is now selling a rival, generic version of Mylan's EpiPen at about a sixth of its price, just months after the maker of the life-saving allergy treatment was eviscerated before Congress because of its soaring cost to ...

Many misuse OTC sleep aids: survey

December 29, 2016

(HealthDay)—People struggling with insomnia often turn to non-prescription sleep remedies that may be habit-forming and are only intended for short-term use, according to a new Consumer Reports survey.

The pill won't kill your sexual desire, researchers say

December 15, 2016

Taking the pill doesn't lower your sexual desire, contrary to popular belief, according to research published in the Journal of Sexual Medicine. The authors of the research, from the University of Kentucky and Indiana University ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.