Experts have called for new trials to see if flu drugs Tamiflu and Relenza will work effectively in a pandemic.
In a report from the Academy of Medical Sciences and the Wellcome Trust, scientists highlighted the “very limited evidence” that such influenza medications would work during an epidemic versus in seasonal outbreaks. This is despite the fact that these drugs are widely stockpiled by governments worldwide.
The authors of the report concluded that the two popular antivirals can reduce the duration of seasonal flu symptoms by 14 to 17 hours. However, the analysis does not support the routine use of the medications for patients due to risks of side effects that may outweigh the benefits - unless the flu strain is specifically severe or the patient is very ill.
If future flu outbreaks are stronger or entail greater risks of death than seasonal outbreaks, treating more people with them may be justified – but with the needed trials, added the report.
Wellcome Trust director Dr. Jeremy Farrar said that the lack of research during the last flu pandemic – referring to the 2009-2010 H1N1 flu virus (swine flu) pandemic when these drugs were widely used – contributed to the weak evidence of effectiveness.
"Research on the use of antivirals – in hospitalized patients and in high-risk groups in a serious epidemic or pandemic – is a priority,” Farrar said, adding that research today, considered “peace time,” could help health care practitioners make the best decisions possible during a pandemic.
Oxford University professor Chris Butler, co-lead author of the review, said that while a lot of Tamiflu were distributed during the H1N1 pandemic, experts “have no idea whether that was right.” He cited “huge opportunities” wasted in the past with the absence of randomized trials.
The report was created following a government request for a report that will assist in future policy decisions. However, it does not recommend whether or not health officials should stockpile flu drugs.
Molecular virology professor Jonathan Ball of the University of Nottingham raised the issue of drug resistance. “We know the virus can become resistant to these antivirals,” he warned, saying it is critical to use the drugs once when there is “clear evidence of their value.”
Ball also mentioned the danger of governments generating profit for pharmaceutical companies through these drugs when there is no clear proof that they work.
Tamiflu is created by Roche while Relenza is a product of GlaxoSmithKline.
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