Wednesday, December 3, 2008

New study confirms: bias in the publication of drug trials is widespread

In its landmark lawsuit against GlaxoSmithKline, the New York State Attorney General accused the pharmaceutical giant of consumer fraud for not publishing negative findings about its antidepressant, Paxil, in essence, for not giving doctors and consumers the full story about its blockbuster drug.

Now comes a new study showing that the practice of selectively publishing only positive results and suppressing negative findings is an industry-wide habit. In a study published last week in PLoS Medicine, researchers at the University of California San Francisco discovered that only three-quarters of the randomized drug trials submitted for New Drug Applications (NDAs) between 2001 and 2002 were eventually published. Even more worrisome, trials with favorable outcomes were nearly five times more likely to be published than those with negative outcomes.

Furthermore, the researchers found evidence that primary outcomes were changed between the time the results were submitted to the FDA as NDAs and the time the studies were published. And when that happened, the results were invariably altered to favor the test drug, the researchers found.

These findings demonstrate that "the information that is readily available in the scientific literature to health care professionals is incomplete and potentially biased," the UCSF researchers conclude.

In an accompanying editorial, a scientist for the Mayo Clinic who previously worked with the World Health Organization's International Clinical Trials Registry Platform, agreed that the "trial literature is biased" and declared that the "the time has come to tackle the challenge of making key trial documents public."

Fortunately, drug companies are now required by law to post the results of all their clinical trials, negative as well as positive, on a publicly available website. And the fact that the leading medical journals now require pretrial registration -- i.e. researchers must post their trial protocols on a public website -- should help cut down on the tendency to change primary outcome measures to favor drug results.

However, drug company-sponsored researchers still don't have to publish the results of all randomized drug trials in medical journals. And since that is where doctors and consumers get most of their information, the full story about the safety and effectiveness of new drugs remains untold.


Anonymous said...

Alison, I started Side Effects a few days ago. I'm only up to page 56. Besides the information and subject matter, it's extremely well-written, easy to follow (especially for a guy like me who often finds it difficult to concentrate).

The first time I went to get treated, circa 1992, I took the MMPI, and shortly after was prescribed Prozac and Stelazine. It was a decade later, when I had Internet, that I learned Stelazine was primarily used to treat psychosis. I had never been diagnosed as being psychotic. A secondary use of Stelazine is for anxiety. That’s why it was given to me. But what I learned about Stelazine is that it’s typically used for anxiety only after other tranquilizers have failed. As I indicated, this was my first time seeking treatment for my depression and anxiety. No other tranks had been tried on me. Stelazine is one of those nasty old drugs that can cause tardive dyskinesia, a long-term, permanent side effect.

After reading in Side Effects how the time of my treatment coincided with negative information leaking about Prozac, I wonder if they didn’t just start me on a powerful anti-psychotic to prevent any “problems.”

It's speculation of course, I have no proof, but I can't help wonder.

I finally got off Stelazine 5 years ago. While I was on it, I’d be in bed 10 to 12 hours a day. Now I sleep an average of 7 hours a night. Often I need a nap during the day. I seem to get tired at certain times of the day, but if I stay up, the drowsiness goes away and I can continue on with my day with a sufficient energy level.

And every p-doc I saw while I was on Stelazine thought my excessive sleeping was due to my depression.

I've been on several other medications, but I'm keeping this to one in particular.

Unknown said...

Yes, it takes some digging to find the Canadian drug trial reporting joint pain as a side effect of Januvia, but not much effort to find multiple reports by consumers online that they are experiencing severe, unrelenting joint pain after starting this drug. Join pain, though, is not listed as a side effect in prescribing information, so those who are suffering from it are assured by their physicians that it's not related to the drug.

How long will it take before the FDA reports this and takes action?