Paroxetine and adult patients

Response to US Senator Grassley

The following is an excerpt from GlaxoSmithKline’s response on 15 February 2008 to a letter from Senator Grassley seeking information on Paxil and adult patients:
 
GlaxoSmithKline has always acted with the best interests of our patients in mind. We have strived for transparency when it comes to safety issues, through timely and complete submissions to FDA, and by posting important and helpful information for physicians and patients on our website.

• The issue raised by Dr. Glenmullen about run-in events is old news. It was debated in the public domain as long ago as 2002. Further, the approach GSK used in 1989 and 1991 in counting placebo run-ins was also used by FDA in its Safety Review of Paxil in 1991.

• Dr. Glenmullen’s report was created to support plaintiffs’ allegations in litigation against GSK. His methodology is scientifically flawed and unreliable; no one but plaintiffs’ experts in product liability litigation use it. A federal court rejected similar opinions when presented by another plaintiffs’ “expert."
  

• In fact, that federal court excluded those opinions because they were not based on “a methodology for determining general causation which has been accepted in the scientific community.”¹
  

• GSK has made Paxil risk information, including information about clinical trials, readily accessible to the public and the scientific community through a clinical trial registry, the GSK website, letters to healthcare professionals and publications in peer-reviewed literature. On GSK’s corporate homepage alone, there is a wealth of information about Paxil, much of which lays out in great detail the various analyses of suicidal thinking and behavior the company has conducted over the years.

• This information demonstrates that GSK detected no signal of any possible association between Paxil and suicidality in adult patients until late February 2006, and even then the finding related primarily to young adults, and to suicide attempts and not completed suicides. The numbers were small and the study was retrospective. GSK promptly contacted FDA, submitted a briefing document to the agency on 8 March 2006, discussed appropriate content for a labeling change, and communicated the findings to healthcare professionals on 5 May 2006.

• In 2007, FDA directed that labeling be revised for the entire class of selective serotonin reuptake inhibitor antidepressants (or “SSRIs”, of which Paxil is one). FDA required that the label state that the number of suicides in the adult trials was not sufficient to reach any conclusion about any effect on suicide. FDA also directed that the label reflect that analyses had detected no increased risk of suicidality (attempts or ideation) in adults above 24 and that there appeared to be a protective effect in adults over 64.

• FDA has systematically monitored the issue of a possible association of antidepressants with suicide and suicide attempts for almost two decades, periodically requesting and receiving from SSRI manufacturers updated, comprehensive information on these events. As early as 1991, FDA concluded that there was no association between SSRIs and suicide/suicide attempts.

• GSK’s 1989 and 1991 analyses of the clinical trial data for Paxil, properly analyzed, revealed no increase in the risk of suicides or suicide attempts for adult patients on Paxil.

1. See Vanderwerf v. SmithKline Beecham Corp., Civil Action No. 05-2271-KHV, slip op. (D.Kan. 9 January 2008).