EVIDENCE that Tamiflu prevents complications such as pneumonia in healthy people who develop seasonal influenza has been questioned by the British Medical Journal (BMJ).
A re-examination of data on the drug oseltamivir, a key part of the global public health defence against swine flu, suggests the anti-viral agent should not be used in the routine control of seasonal influenza. However, the authors of the review add: “We are unsure of the generalisability of our conclusions from seasonal to pandemic influenza.”
They do not rule out the possibility that Tamiflu may reduce the incidence of pneumonia and other complications in otherwise healthy adults.
The charge could cause concern among governments in countries, including Ireland, that have stockpiled Tamiflu in the belief that its active ingredient, oseltamivir, can cope with such complications.
"Governments around the world have spent billions of pounds on a drug that the scientific community now finds itself unable to judge," said Dr Fiona Godlee, editor-in-chief of the BMJ.
A research team commissioned by the journal and Channel 4 News and led by Prof Chris Del Mar from Bond University in Australia analysed 20 published trials focusing on prevention, treatment and adverse reactions.
Eight trials were dropped by the team because they were never completed, while the scientists said their investigations was hampered by the “paucity of good data” available from both authors and the drugs company.
“As a result, they conclude that they have no confidence in claims that oseltamivir reduces the risk of complications of influenza in otherwise healthy adults, and believe it should not be used in routine control of seasonal influenza,” the journal said.
Swiss-based pharmaceutical company Roche, which produces oseltamivir, is understood to have sold more than €1 billion worth of oseltamivir this year alone, but has been criticised by researchers for not publishing enough information about the drug.
The use of neuraminidase inhibitors such as oseltamivir increased significantly after the spread of the A/H1NI swine-flu influenza began in April given the lack of an effective vaccine and known resistance to other forms of flu treatments.
Prof Nick Freemantle and Dr Melanie Calvert from the University of Birmingham concluded that “oseltamivir may reduce the risk of pneumonia in otherwise healthy people who contract flu”, but “absolute benefit is small”.
The investigation raised concerns about the alleged use of “ghostwriters” in some of the studies published and questioned why the results of the largest trial into oseltamivir were never published. Last night, Roche said it “firmly believed in the robustness of the data”. However, it is now to publish extra information.
The HSE said it would consider the report in the BMJbut it had no plans to change prescribing guidelines. A spokeswoman said the policy in relation to the prescribing of Tamiflu in the Republic has been different to that of the UK since the pandemic began.
In the UK, she said, it was given out more liberally. “In contrast, our prescribing has been limited to those who are severely ill or are in one of the at-risk groups.”