Seven Year Itch

Seven year itch

Like romance, pharmaceuticals can be risky.

When the FDA approves a drug, it’s sort of like the agency sets up U.S. consumers on a blind date. At that point, we know some of the basics about the drug, but those basics are nothing compared to what we’ll know in a few years, after additional studies are completed and adverse events are reported.

In 1999 we went out on our “first date” with Tamiflu, a drug designed to reduce flu symptoms. Tamiflu doesn’t prevent the flu, but when administered quickly at the outset, it may cut the duration of flu symptoms by a day or so.

Now, seven years later, something peculiar is happening to some of the youngest patients who take Tamiflu. And no one knows why.

Shock to the system

A 2005 FDA safety review identified disturbing adverse events associated with Tamiflu use in children under the age of 16. According to the FDA, “These adverse event reports were primarily related to unusual neurologic or psychiatric events such as delirium, hallucinations, confusion, abnormal behavior, convulsions, and encephalitis.”

Most of those events were reported in Japan, where Tamiflu use is about four times greater than in the U.S. A dozen deaths among pediatric patients were also associated with Tamiflu use (although no evidence directly blames the drug for those deaths).

Here’s where it gets mysterious. Between 1999 and 2005, 126 adverse events were reported. But between the summer of 2005 and the summer of 2006, 103 new adverse reports were filed. Health officials are baffled by this sudden spike.

The FDA is now considering a change in Tamiflu labeling that would include new warnings for parents to closely monitor children who take the drug. Tamiflu sold in Japan already carries a warning about potential “abnormal behavior” in pediatric use.

So it’s time for a little “water cooler” regulation. While the FDA jumps through the bureaucratic hoops of committees and advisory panels, the rest of us can go ahead right now and let friends and family know that kids taking Tamiflu may be at risk.

Back up the Tamiflu truck

In an Associated Press article about the unexplained adverse events in children, this sentence stood out: “Tamiflu is one of the few drugs believed effective in treating bird flu.”

Well not exactly.

The U.S. government would certainly like for everyone to believe that a round of Tamiflu might prevent the predicted dire effects of avian flu. According to a March 2006 report in USA Today, the federal government has already purchased about 17 million Tamiflu treatments, with plans to eventually purchase more than 700 million treatments. But does the evidence really support this wild buying spree?

In an e-Alert I sent you last January, I told you about a 2005 New England Journal of Medicine (NEJM) article with details about two Vietnamese patients with avian flu who were treated with Tamiflu shortly after symptoms were identified. Both patients died. But they didn’t die because Tamiflu was ineffective. They died because the virus quickly developed resistance to Tamiflu.

Writing in NEJM, Anne Moscona, M.D., a Cornell University medical professor, noted that the misuse of Tamiflu stockpiles may promote resistance, lessening the usefulness of the drug. She concluded that personal stockpiling should be strongly discouraged.

According to ABC News, a representative of Roche Laboratories, Inc. (the maker of Tamiflu) reacted to the NEJM report with a news briefing about eight avian flu patients who were treated with the drug. Four of the patients showed a drop in viral levels and survived. The other four patients died.

Obviously, the Roche rep offered this as evidence that Tamiflu is effective against the virus. He didn’t happen to mention, however, that among the approximately 120 people who have contracted avian flu over the past two years, about half have survived – a perfect mirror image of his eight case studies.

There is zero scientific evidence that Tamiflu would be effective in treating cases of the avian flu. Zero.