It's a one-two punch for Roche from Tamiflu this week. No sooner had the drugmaker reported declining sales, in part on weaker sales of the antiviral drug, than the CDC announced that this year's flu is almost 100 percent resistant to it.
Part of Tamiflu's problem is its own success. Governments around the world have stockpiled 220 million doses of the drug, Roche said Wednesday. Though that number is dwarfed by actual population figures, it's still a lot of stockpiling. As governments have slowed down on their cache-building--or supplemented with GlaxoSmithKline's Relenza because of resistance concerns--Tamiflu sales dropped a whopping-though-expected 68 percent last year.
Those resistance concerns are obviously growing: CDC told docs to use Relenza for H1N1 flu patients instead, or to use Tamiflu with the old standby rimantadine. And experts are advising governments to add Relenza to their antiflu stocks rather than more Tamiflu. "There have been people, and I'm one of them, that have suggested that there be more of an equal stockpiling of oseltamivir and zanamivir," Dr. Anne Moscona, a pediatrician and professor at New York-Presbyterian Hospital/Weill Cornell Medical Center, told the Los Angeles Times.
At least for now, the deadly H5N1 avian flu circulating in Asia is still responsive to Tamiflu, if it's given to patients early on. We'll have to wait and see whether that continues.