Europe's drug watchdog on Friday recommended that the shelf life of Roche's Tamiflu should be extended to seven years from five years due to the outbreak of the new H1N1 virus.
Tamiflu, along with GlaxoSmithKline's Relenza, is an antiviral shown to be effective over the new infection, dubbed swine flu, that first emerged in Mexico and has pushed the world to the edge of a pandemic.
Once formally approved by the European Commission, the new guidelines from the European Medicines Agency would apply to all newly manufactured Tamiflu capsules, it said.
The watchdog also called for tablets already on the market to be used for up to two more years after their current five-year expiry date during a declared pandemic and recommended wider use of both Relenza and Tamiflu.
"Patients who have Tamiflu capsules that have recently expired should not dispose of them because they might be needed during a novel influenza A/H1N1 pandemic," the London-based agency said.
It also issued guidance that in a declared pandemic children under the age of one should receive Tamiflu because the benefits would outweigh the risks.
The agency said it also concluded after a review of available data for Tamiflu and Relenza that pregnant and breastfeeding women should also be prescribed the drugs if needed during a pandemic.
"These recommendations will only apply if a pandemic has been declared by the World Health Organization," the agency said.
Governments in many countries are stockpiling antivirals to deal with a widely expected H1N1 swine flu pandemic, with most of the stocks comprising Tamiflu, known generically as oseltamivir.
Tamiflu, which is taken as a tablet, is more convenient than Relenza, or zanamivir, which must be inhaled. Tamiflu and Relenza are the only approved drugs to which the new H1N1 strain has been found to be susceptible.
Roche and Glaxo are both expected to enjoy windfall gains from sales of their medicines, and the two companies are racing to increase production capacity to keep up with demand.
A Roche spokeswoman said she expected the decision to be implemented quickly, adding it does not mean the company has to change its production of tamiflu in any way.
She declined to comment on what impact the decision would have on demand for Tamiflu, but reiterated that Roche was increasing production in response to the H1N1 outbreak.
According to the latest WHO tally, 2,384 people in 24 countries have been infected with the newly emerged strain that scientists say is a mixture of swine, human and bird viruses.
Young adults have been most heavily infected by the new virus, which has killed 44 people, all but two in Mexico, according to the WHO.
Reuters