Antidepressant Reboxetine ineffective: Review

By Dr. Ananya Mandal, MDOct 13 2010

According to a new study, an antidepressant prescribed over the last 13 years is ineffective and potentially harmful. The drug in question is called Reboxetine and is available under the name of Edronax. The study showed that it works no better than a placebo.

The study appeared in the British Medical Journal. Manufacturer Pfizer is accused of failing to disclose the results of trials which show its inadequacies. In UK the licensing authorities and Nice, the National Institute for Health and Clinical Excellence are now looking at the drug again.

The study was conducted at the German Institute for Quality and Efficiency in Health Care. Independent scientists decided to scrutinize the data on reboxetine because of doubts that have been raised about its effectiveness and the fact that the US licensing authority, the Food and Drugs Administration (FDA) refused it a license in 2001. They found that isolated trials that have been published and reviews of the data in the public domain have all shown the drug to be effective. But the German institute's scientists found that eight out of 13 significant trials had not seen the light of day. Pfizer had provided data from 1,600 patients only but trials included 4,600. Pfizer stated publicly it had given the institute “those data that from our point of view are suited for a benefit assessment of Edronax”, but eventually handed over most of the rest.

Now the institute accuses the manufacturers of publishing only positive results for the drug. “Data on 74% of the patients included in our analysis was unpublished, indicating that the published evidence on reboxetine so far has been severely affected by publication bias…Our comparison of published and unpublished trials confirmed this assumption: the positive benefit-risk ratio of reboxetine in the published literature was changed to a negative ratio if unpublished trials were added to the analysis,” the authors write.

According to Beate Wieseler, deputy head of the institute's department of drug assessment and colleagues the European laws need to be changed to make it mandatory for all clinical trial results to be published. They argue that all trial data should be disclosed – even when the trials fail and the drug is not approved.

Robert Steinbrook from Dartmouth and Yale and Jerome Kassirer from Tufts University schools of medicine in the US in another commentary state that there have been recent controversies of similar nature related to drugs like Avandia for diabetes and the painkiller Vioxx that had safety problems. They write, “Companies have financial interests in the outcome of the studies they sponsor; they own the data, and set the rules for access to the data. Unfortunately, they cannot be relied on to consistently provide dispassionate evaluations of their own drugs and medical devices.”

According to editor of the BMJ Dr Fiona Godlee and her colleague Dr Elizabeth Loder “the medical evidence base is distorted by missing clinical trial data.” “Full information about previously conducted clinical trials involving drugs, devices and other treatments is vital to clinical decision-making…It is time to demonstrate a shared commitment to set the record straight,” they said.

A spokeswoman from Pfizer said, “Pfizer will review the meta-analysis relating to reboxetine published in the British Medical Journal on 13th October 2010 in detail and will provide further comment after completing the review.”