Friday, September 25, 1998 Published at 17:27 GMT 18:27 UK
Flu pill 'could bring relief'
Flu costs Britain over £6bn a year in days off work
A new pill which attacks the virus which causes flu could reduce the number of days a person is ill and the severity of their symptoms.
A cure for the most common strains of flu has been one of the Holy Grails of medicine.
The virus affects four to 15% of Britons under 20 every year. Around 150m working days a year are lost because of flu, at a cost of £6.75bn.
Until now, there have only been vaccines against flu and medicines to reduce the symptoms, such as sore throats and fever.
But drug manufacturer F. Hoffmann-La Roche Ltd and biotechnology firm Gilmead Sciences Inc. have come up with a drug which attacks the virus itself.
The drug, called GS4104, was tested in two trials: one on 629 patients in the USA and the other on 719 patients in Europe, Canada and China.
The drug reduced the number of days the Americans were sick by 33% and made their symptoms 40% less severe.
It also halved the risk of developing secondary infections such as bronchitis in people who were originally healthy.
The Europeans, Canadians and Chinese were ill for 30% less time and their symptoms were 25% less strong.
The researchers say it is impossible to completely eradicate the virus once a person is infected.
This is because the flu virus mutates very fast, becoming resistant to treatments.
GS4104 works by blocking an enzyme in the flu virus so that it cannot infect new cells.
Researchers will present their findings on the drug, which has passed through the last tests it needs before it seeks regulatory approval, at an American Society of Microbiology meeting in San Diego on Friday.
Glaxo Wellcome will also tell the meeting about its flu drug Zanamivir, which works in a similar way to GS4104, but is used with an inhaler.