Study: Who's paying affects trial results

SAN FRANCISCO, June 4 (UPI) -- In head-to-head trials of two drugs, the one deemed better appears to depend largely on who is funding the research, a new U.S. study said.

An examination of 192 trials comparing one cholesterol-lowering statin to another, or to a non-statin drug, found results favoring the test drug in the trial were about 20 times more likely to be funded by the maker of the statin than the comparison drug company, according to a study by University of California, San Francisco, researchers appearing June 7 in the journal PLoS Medicine.

"If drug trial outcomes are largely determined by who pays for the trial, we don't really know what the best drug is," said study author Lisa Bero, professor of clinical pharmacy and health policy studies at the university.

There are several possible reasons for the result, the researchers wrote. Drug companies could be only funding trials they think will favor their drugs, or they could simply be choosing not to report unfavorable results. They could also be rigging results by giving the drugs in non-equivalent doses.

In addition, almost half of the trials lacked adequate blinding, the process assuring that study scientists don't know which drug the patients were taking until the end of the trial. Blinding is considered an important element of non-biased research.