Report shows Pfizer's hand in Neurontin studies

By Julie Steenhuysen

CHICAGO (Reuters) - A study of internal company documents suggests Pfizer Inc altered or omitted unfavorable study findings to expand its epilepsy drug Neurontin's market, U.S. researchers said on Wednesday, offering a look at how drugmakers influence scientific research.

Clinical trials are supposed to answer a specific, predetermined scientific question, but a comparison of Pfizer documents and published studies on Neurontin for conditions other than epilepsy found that eight out of 20 study reports never made it into medical journals.

And in eight of the 12 published studies, the primary outcome -- the answer to the main scientific question -- was changed by Pfizer, the world's biggest drugmaker, from the original study design.

"There were a lot of primary outcomes that were shifted around between the planning of the protocol and the reporting of the study," said Kay Dickersin of Johns Hopkins University in Baltimore, whose study appears in the New England Journal of Medicine.

"Some primary outcomes were lost altogether. Some were brand new. Some were secondary outcomes that were upgraded to primary," she said in a telephone interview.

The studies, all funded by Pfizer, showed how the drug worked in people with problems like migraines or pain, which are off-label uses of the drug.

Once a drug is approved, doctors are free to prescribe it as they see fit, and while companies are not permitted to market a drug for anything but the approved use, they can hand out reprints of studies published in medical journals showing how the drugs work in patients with different problems.

Dickersin got the documents while serving as an expert witness against Pfizer, which in 2004 paid $430 million to settle a lawsuit over illegal promotion of Neurontin.