If any more evidence were needed that concealing negative data about (at least) antidepressants is a standard business plan among pharmaceutical companies, we can turn to: http://www.iqwig.de/index.981.en.html?random=6f6241
The German Institute for Quality and Efficiency in Health Care set out to decide whether three newer antidepressants, reboxetine (Edronax), bupropion XL (an extended release form of Wellbutrin), and mirtazapine (Remeron) actually work and show any advantages over other antidepressants. I'll let them tell the story:
"In its preliminary report published at the beginning of June 2009, the only results IQWiG could present without reservation were those for bupropion XL. It was forced to add a caveat to the results for mirtazapine, because the fact could not be ignored that study data not provided by Essex Pharma might seriously bias the result. In the case of reboxetine, IQWiG abandoned its analysis of the study data that was publicly available at that time, because it was evident that the manufacturer, Pfizer, was concealing almost two thirds of all data collected in trials to date. An analysis of the available data would have produced a biased picture. Despite several requests, Pfizer had steadfastly refused to provide IQWiG with a list of all published and unpublished data.
"However, after the preliminary report was published, Pfizer and Essex Pharma decided to make the unpublished data and information on trials accessible. Only then was it possible to assess all three drugs based on complete data.
"The analysis of the complete data reveals that IQWiG made the right decision in abandoning its assessment of reboxetine based only on published data. The summary of results from published and non-published trials does not provide proof of benefit of reboxetine, whereas the data from the published trials appear to suggest a benefit."
They went on to report that reboxetine, in addition to showing no benefit compared to placebo, did demonstrate risks of harm compared to either placebo or fluoxetine (Prozac). They proceeded to report some benefits from mirtazapine and more substantial benefits from bupropion XL.
The organization concluded: "This case re-emphasizes the need for a mandatory regulation, which would require all clinical trials to be registered at the start and to have their results published after study completion."
I'm indebted to Jörg Schaaber (Editor, Pharma-Brief, BUKO Pharma-Kampagne, Bielefeld, Germany) for the e-mail notification of this statement (via the Healthy Skepticism members' listserv).