Recently published research reports serious design flaws in many of the pharmaceutical studies involving animals that precede drug trials in humans.
A research team led by pharmacologist Lisa Bero of the University of California, San Francisco, analyzed animal studies of popular cholesterol-lowering statin drugs including Crestor (rosuvastatin), Lipitor (atorvastatin), and Zocor (simvastatin), HealthDay News reports. The study was published online in PLoS Biology.
The 63 studies had a variety of funding sources; some government funded, some funded by drug companies, the rest by non-industry sources. Regardless of funding type, the researchers found serious design flaws in many of the trials. About half the time, the animals involved were not randomly divided into treatment or placebo groups, or the animals were identifiable to the person administering the drug or the placebo, in violation of the proper research practice of “blinding,” in which researchers do not know which subjects received the treatment and which did not. In many of the studies reviewed, criteria for including or excluding animals were not properly explained and many studies did not explain treatment changes in groups of animals that were being given the drugs. Lastly, many studies did not investigate the harmful side effects of the drugs in the trial.
In a university news release, Bero wrote, “Not a single animal study we looked at assessed adverse events following the statin intervention,” according to HealthDayNews. She called it “surprising” that so little data on harm appears in the published literature because toxicity data from animal studies must be submitted to regulators before a drug tested in animals can proceed to testing in humans.
Bero also noted that while most of the studies put forth favorable conclusions, drug-company-sponsored trials were more likely to present favorable conclusions, even where there was less favorable data about the drug, HealthDay News reports.