Study assesses the effects of neuraminidase inhibitors in preventing or improving the symptoms of influenza

Diciembre 08/09

Data from 20 studies in healthy adults suffering from influenza suggested that there is no clear evidence that neuraminidase inhibitors, such as Roche's Tamiflu (oseltamivir), prevent complications like pneumonia, according to an analysis published in the BMJ on Tuesday.

Lead researcher Tom Jefferson of the Cochrane Collaboration commented: "We now conclude there is insufficient evidence to describe the effects of Tamiflu on complications of influenza or the drug’s toxicity… We have multibillion-dollar public health policies in place that rely on evidence not available for independent analysis."

The review involved data from 20 randomised, placebo-controlled studies of neuraminidase inhibitors that included four trials on the prevention of naturally occurring influenza, 12 for treatment, and four on prevention following exposure to influenza. Jefferson noted that "the evidence shows that if taken within 24 hours, Tamiflu reduces symptoms of influenza by about a day… It may reduce transmission. But we could not verify the claims that Tamiflu reduces complications."

Researchers said that Roche's drug "did not reduce influenza-related lower respiratory tract complications," and they indicated that adverse events associated with Tamiflu were "possibly under-reported." Commenting on the news, BMJ editor, Fiona Godlee, and the director of the UK Cochrane Centre, Mike Clarke, remarked that the review raises concerns "not only [about] the effectiveness of oseltamivir but the whole system by which drugs are evaluated, regulated and promoted."

They wrote in an accompanying journal commentary that "pending full disclosure and independent review of the raw data from Roche, the risks and benefits of oseltamivir remain uncertain." The head of Roche's global pandemic task force, David Reddy, stated that the drugmaker "fully stands behind the robustness of the data and the integrity of that data, particularly the efficacy and safety of Tamiflu, the conduct of our studies and publication policies." A spokesperson for the company noted that study summaries of the antiviral drug would be made available to the scientific community. An antivirals expert from the World Health Organization, Charles Penn, said the agency would not change its guidelines for Tamiflu use based on the latest news.

Fuente original: Neuraminidase inhibitors for preventing and treating influenza in healthy adults: systematic review and meta-analysis - (BMJ)