Tamiflu has only 'modest effectiveness' against swine flu complications, experts warn
By Lilian Anekwe
Several leading respiratory experts have questioned the use of Tamiflu to prevent swine flu complications, in a new review raising fresh questions over the Government's response to the pandemic.
A gold-standard review found Tamiflu and other neuraminidase inhibitors have only ‘modest effectiveness' against the symptoms of influenza in otherwise healthy adults
But the authors bemoaned a ‘paucity of good data' on the efficacy of Tamiflu to prevent complications like pneumonia in healthy people, which they say calls into questions the Government's strategy, and its decision to spend an estimated £500m on stockpiling antivirals for use in the swine flu pandemic.
The research team, which includes Dr Tom Jefferson, a former GP and a researcher at the Cochrane acute respiratory infections group, analysed 20 randomised controlled trials to examine the evidence for the use of antivirals to reduce the duration and incidence of symptoms, the incidence of lower respiratory tract infections, and adverse events.
The efficacy of Tamiflu against symptomatic laboratory-confirmed influenza was 61% at 75 mg daily and 73% at 150 mg daily. Oseltamivir for post exposure prophylaxis had an efficacy of between 58% and 84%. Relenza performed similarly.
But the researchers were forced to disregard eight trials which were never fully published because they were unable to independently verify the results, and accused Roche, the manufacturers of Tamiflu, of making ‘contradictory statements about the potential benefits of Tamiflu.'
And in an accompanying feature, Professor Nick Freemantle, professor of clinical epidemiology and biostatistics at the University of Birmingham, said: ‘We have remarkably few resources in this country to spend on pharmaceuticals on health and it's surprising to see such widespread use of oseltamivir.'
‘But I suppose that once you've gone and bought lots of doses then it's a bit like the situation with gun control in the US. If you have a gun in the house it's much easier to use it. But it does not mean it's the right thing to do.'
A spokesperson for the DH said: ‘The Cochrane review is an analysis of the use of Tamiflu to treat H1N1 influenza in healthy adults based on work on seasonal influenza.'
‘It doesn't cover people with underlying health conditions, or children, and we know that it may not be appropriate to generalise from effects in seasonal flu to those in a pandemic.'
‘Unlike seasonal flu, swine flu has caused higher levels of severe illness in the young and healthy, and in some cases death. While there are still significant levels of H1N1 circulating, our strategy remains to offer antivirals to all patients with the illness.'
James Smith, international medical leader for Roche, said: ‘We would emphasise that the benefits of oseltamivir have been shown in randomised controlled clinical trials, not simply through observational trials.'
‘Professor Freemantle's point about benefits may be the case in seasonal influenza where complications are relatively infrequent, but can change with increasing pathogenicity of either avian or pandemic viruses.'
The investigation was conducted jointly by BMJ.com and Channel 4 news.The study has called the effectiveness of Tamiflu into question The study has called the effectiveness of Tamiflu into question