The older flu drugs, amantadine and rimantadine, are not effective in treating influenza, have serious side effects and should not be used to treat either seasonal or pandemic influenza, according to new research from scientists at the US Cochrane Collaboration and published early on The Lancet’s website this week.

The news is probably not unexpected as, earlier this month, the US Centers for Disease Control itself said that, because of increasing resistance of the influenza A virus to amantadine and rimantadine, the drugs should not be used for treating influenza and should be substituted for either GlaxoSmithKline’s Relenza (zanamivir) or Roche’s Tamiflu (oseltamivir).

However, what has got pharma companies’ knickers in a twist is the Cochrane Collaboration’s intimation that the neuraminidase inhibitors, Tamiflu and Relenza, should “not be used in seasonal influenza control and should only be used in a serious epidemic or pandemic alongside other public health measures.” The meta-analysis also stated: “We could find no credible data on the effects of [Tamiflu] on avian influenza.”

Publication of the Cochrane Review triggered a credulous response from the Swiss giant. “Roche fundamentally disagrees with the conclusions reached by the authors that [Tamiflu] should not be used for the treatment and prevention of seasonal influenza. The statement by the author that neuraminidase inhibitors should not be used in seasonal influenza control is inappropriate and inconsistent with the data.”

Fears of a pandemic of bird flu have caused governments worldwide to stockpile Tamiflu, triggering a massive explosion in sales for the Swiss giant, with revenues for 2005 expected to jump significantly – potentially nudging over the 1 billion Swiss francs ($788 million) mark. For the first three quarters of last year, Tamiflu revenues were hiked a staggering 263% to 859 million francs.