Warning on Tamiflu deaths10th March 2008
Two pharmaceutical companies have strengthened warnings on their prescription influenza medications following reports of abnormal psychiatric side-effects in some patients.
Roche Holding AG and GlaxoSmithKline plc have added a warning about cases of delirium and unusual behavior listed previously on Roche's drug, Tamiflu, strengthening the language to point out that some of the reported cases had been fatal.
Reports had been received by drug regulators after Tamiflu's approval by the United States Food and Drug Adminstration (FDA) detailing side-effects including psychiatric abnormalities which had led to injury and even death in some cases, according to a letter from Roche to doctors dated February 2008.
The letter's contents were also posted on the FDA website.
The label also warns that such symptoms can sometimes be caused by influenza itself, which has been linked with various neuropsychiatric problems, and that the contribution of Tamiflu to the reported events had not been established.
GSK has added a similar warning about delirium and abnormal behaviour to the label for its influenza drug, Relenza.
It also says that the contribution of Relenza to these events has not been established, and both drug labels say the cases "appear to be uncommon."
The change in wording comes after an FDA advisory panel reviewed the cases, which were mostly reported in Japan, in November 2007.
About 700 cases of psychiatric adverse events for both drugs were reported to that panel, along with 25 cases of paediatric deaths in patients taking Tamiflu, or oseltamivir. No deaths were reported for Relenza, also known as zanamivir.
Tamiflu is being added to large government stockpiles around the world, as it has shown some effectiveness in the early treatment of avian influenza, which global health experts fear may cause the next influenza pandemic, killing millions.
Both drugs are also used in the treatment of seasonal, type 'A', influenza.
Roche said in a statement that the changes to the label reflect observations from a growing body of data, but that no evidence of a causal relationship between Tamiflu and the reported adverse events was shown.
GSK said it would soon also send a letter to doctors about the new warning on Relenza.
The labels say patients with the flu should be closely monitored for signs of abnormal behavior, and the risks and benefits of continuing treatment should be evaluated on an individual basis, should neuropsychiatric symptoms occur.
Share this page
There are no comments for this article, be the first to comment!
Post your comment
Only registered users can comment. Fill in your e-mail address for quick registration.
Title: Warning on Tamiflu deaths
Author: Luisetta Mudie
Article Id: 5933
Date Added: 10th Mar 2008