Scientists conclude there is insufficient evidence to back the government’s decision to stockpile the drug Tamiflu to tackle pandemics such as the outbreak of swine flu in 2009.
Following an investigation spanning five years, an international team of scientists today concluded that there is insufficient evidence to support the use of anti-flu drug Tamiflu as an effective treatment for pandemic flu – and its potential harms could outweigh its benefits.
As well as questioning whether stockpiling Tamiflu for use in a flu pandemic was waste of taxpayers’ money, the report points to what experts call a “multi-system failure” surrounding the way drugs are developed, licensed and marketed.
Between 2006 and 2013 the British government spent £609 million on a stockpile of antiviral drugs in preparation for a flu pandemic: £473 million on Tamiflu and £136 million on Relenza.
During the swine flu pandemic of 2009 more than 150,000 packs of the drug were distributed to people with flu symptoms.
The new analysis published in the BMJ is by an independent coalition of academics called the Cochrane Collaboration. They looked at 170,000 pages of evidence of original drug company trial data for the anti-flu drugs called neuraminidase inhibitors: Tamiflu made by Swiss company Roche and Relenza made by GSK.
It found neither medicine is very good at treating flu.
In the case of Tamiflu the recovery time for flu – typically a week-long illnes – was reduced by 16.8 hours.
But more importantly, when it comes to a flu pandemic, the data showed little evidence of the drugs working to reduce hospital admissions or prevent complications from flu. It is these complications, like pneumonia, which are the main cause of deaths from flu.
Crucially the re-analysis also found that Tamiflu also caused nausea in around 4 per cent of adults and 5 per cent of children. It also found a 1 per cent increased risk of psychiatric events including depression in trial participants taking the drug. Tamiflu does include these risks on its label.
“This review clearly recommends that guidance on the use of neuraminidase inhibitors (Tamiflu and Relenza) in the prevention or treatment of influenza should be revised to take account of the evidence of small benefit and increased risk of harms,” the review authors said.
The report acknowledges Tamiflu may still have a role to play in treating very sick people with flu.
However its authors say the evidence questions its use as a drug to prevent the spread of flu or save significant numbers of lives in a life-threatening flu pandemic.
What we now know about Tamiflu began with an investigation by Channel 4 News and the BMJ in 2009.
Researchers from the Cochrane Team who were trying to independently assess the effectiveness of Tamiflu found data published in scientific journals was insufficient to support the manufacturers claims for the medicine.
They tried, and failed, to get hold of trial data on Tamiflu from the drugs manufacturer Roche and or regulatory authorities in the US and Europe. But none would surrender it.
Then, in an interview with Channel 4 News in 2009 Dr David Reddy, Head of Roche’s Global Pandemic Preparedness Task Force told Channel 4 News: "All trial data would be made available."
Despite the promise it still took nearly four years for them to surrender it.
But finally in April last year, they did. The results of today's analysis are based on that data.
Aside from questioning the effectiveness of Tamiflu, the Cochrane team say their analysis highlights major problems over the transparency of data on important public health medicines.
What we’ve put on the label is what we can stand by and is what the data shows Dr Barry Clinch, Principal Clinical Scientist, Roche
“Drug approval and use can’t be based on biased or missing information any longer,” said the Cochrane team. “We urge people not to trust in published trials alone or on comment from conflicted health decision makers, but to view the information for themselves.”
In response to the findings Roche told Channel 4 News that follow-up analysis of Tamiflu from during the 2009 flu pandemic shows it is an effective drug.
“We feel that what we’ve said all along and what we’ve put on the label is what we can stand by and is what the data shows,” Dr Barry Clinch, Principal Clinical Scientist at Roche told Channel 4 News.
The company maintains a new analysis published last month in the Lancet medical journal supports the continued use of Tamiflu in pandemics. The study reports a 20 per cent reduction in deaths from flu following early treatment with the drug.
However the report was paid for by Roche and its lead author, now an independent academic, used to work for the company.
In response to today’s report the Department of Health said: “The UK is recognised by the World Health Organisation as being one of the best prepared countries in the world for a potential flu pandemic. Our stockpile of antivirals is a key part of this.
“Tamiflu is licensed around the world for the treatment of seasonal flu and is a licensed product with a proven record of safety, quality and efficacy.
“We regularly review all published data and will consider the Cochrane review closely.”