The Epoch Times, November 1, 2010
by Dr. John Briffa
If we wanted to find out if a drug or another treatment were any good, we would have to conduct some randomized controlled trials. This means individuals are randomly assigned to the drug being tested, a placebo, or another drug.
Neither the researchers nor the study participants know what’s being taken. Symptoms or other markers of health are monitored as well as side effects. After a period of time, the code is cracked, and we can learn who was taking what.
Now we can know if the drug being tested was more effective at helping people than the placebo and how safe it is. A few studies showing favorable results will usually get a drug passed as “fit for purpose.” This is how drugs end up getting licenses so that doctors can prescribe them to their patients.
Not so fast. While some (often the manufacturers) claim that there is a lot of research supporting a drug, it can sometimes be the case that the published research does not tell the full story.
Sometimes there exists other research that is not so supportive of the drug being tested—research that may not have seen the light of day. Drug companies want to publish supportive studies and shelve more-negative findings. There is an expression for this practice—publication bias.
Publication bias has gone on for decades but only relatively recently have some members of the scientific community taken steps to stamp it out. One huge step forward has been a decision in the United States for trials to be registered on a central database before or during a trial. That way the study has been logged, and if the results mysteriously fail to appear, then questions can be asked.
Not so long ago, trial results had to be forced out of the drug companies making the cholesterol-reducing agents simvastatin and ezetimibe. It took two years for the manufacturers to cough up their data after the conclusion of the study. Once the data came out, we learned why: This drug combo didn’t work to reduce signs of cardiovascular disease.
Subsequent studies have also proved negative. Not that long ago, such data would have been easily hidden, even from prying eyes. These days, drug companies don’t have things so easy.
Things are better now than they were. Now a natural question to ask is how many drugs earned their stripes based on publication bias? Some principled researchers are keen to answer this question by reassessing drugs using not only published data but also unpublished data.
An example of such a piece of work appeared online on Oct. 12 in the British Medical Journal. German researchers decided to assess unpublished and published data on the anti-depressant reboxetine, a relatively new type of antidepressant.
Reboxetine is a serotonin-norepinephrine reuptake inhibitor (SNRI). This means it helps maintain brain levels of the chemical norepinephrine, which is believed to enhance mood. It is similar to the more commonly prescribed anti-depressants known as the selective serotonin reuptake inhibitors or SSRIs.
Previously published evidence showed that reboxetine was more effective in treating depression than placebo and was about as effective as the commonly prescribed SSRIs. It’s been licensed for use for depression in many European countries, including the U.K. and Germany, since 1997.
The researchers found that almost three-quarters of data on reboxetine was unpublished. This is disquieting in itself. And when they put this data into the mix, an altogether different picture emerged. When the totality of the evidence was assessed, it turns out that reboxetine was no better than placebo. Most researchers would summarize this by concluding that it doesn’t work.
Perhaps not surprisingly, reboxetine turns out to cause more harm than placebo and more adverse effects than the most-commonly prescribed SSRI (fluoxetine). The authors conclude that reboxetine is “an ineffective and potentially harmful antidepressant.” Yet here in Europe, it’s been licensed for more than a decade.
The authors of this re-analysis mention that here in the U.K., the National Institute of Health and Clinical Excellence (NICE) describes reboxetine as “superior to placebo and as effective as other antidepressants in the treatment of depression.” As the authors point out, “This conclusion can no longer be upheld.”
It is interesting to note that in the United States, reboxetine was originally licensed, but then its license was revoked. While it appears the U.S. authorities made the right decision, the discrepancy with some European countries suggest that the U.S. authorities had more data to go on or perhaps set different licensing criteria.
Such discrepancies and this flagrant example of publication bias do not instill confidence.
The good news is that at least some researchers are not content to do what paymasters in industry tell them to and genuinely appear to be seekers of the truth. I’d say we could expect many more skeletons to emerge from the closet over the coming years.
http://www.theepochtimes.com/n2/content/view/45212/
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