CMAJ (the journal of the Canadian Medical Association) has published details of an internal document from the drug company GlaxoSmithKline that advised its staff to withhold the findings of a clinical trial in 1998 showing that the antidepressant paroxetine had no benefit in treating adolescents.
The association has publicised the document on its website in an early release of its Analysis column (www.cmaj.ca).
Last year, the drug, which is marketed as Paxil in North America and Seroxat in the United Kingdom, was banned for paediatric use in several countries because of a perceived increased risk of suicide.
The UK Medicines and Healthcare Products Regulatory Agency advised doctors last June that they should not prescribe the drug to patients under the age of 18.
The CMAJ column says the confidential document was prepared by the central medical affairs team, a division of SmithKline Beecham, the company that subsequently merged with GlaxoWellcome to form GlaxoSmithKline. The column says the document gives guidance on two clinical trials, study 329 and 377, whose results were, according to the document, “insufficiently robust” to support application to regulatory authorities for a label change approving Seroxat for use in children and adolescents.
The team recommended the firm “effectively manage the dissemination of these data in order to minimize any potential negative commercial impact.”
Study 329, conducted in the United States from 1993 to 1996, showed paroxetine to be no more effective than a placebo, while study 377 showed that the placebo was “actually more effective than the anti-depressant.”
The central medical affairs team's document is quoted as saying that “it would be commercially unacceptable to include a statement that efficacy had not been demonstrated, as this would undermine the profile of paroxetine.”
A spokeswoman for GlaxoSmithKline, Jill McKinlay-Morris, told the CMAJ that “the memo draws an inappropriate conclusion and is not consistent with the facts... GSK abided by all regulatory requirements for submitting safety data. We also communicated safety and efficacy data to physicians through posters, abstracts, and other publications.”