Influenza affects hundreds of millions of people annually
Influenza, commonly called 'the flu', affects five to 10 per cent of adults and 20 to 30 per cent of children around the world each year. The economic impact is substantial in terms of days off work and productivity lost each year.
In high-risk groups, complications of influenza such as pneumonia can be fatal. People at high-risk include:
- the elderly
- those with chronic respiratory problems
- those with diabetes
- those with cardiovascular disease.
In a typical Australian winter, around 3000 deaths are caused either directly by the flu, due to complications of the flu or from pneumonia.
The flu virus mutates rapidly. Humans suffer repeat infections as the immunity we develop to one infection does not protect us from subsequent mutant viruses.
Breakthrough discovery unlocks mutation pattern
In collaboration with research partners and industry, we have revolutionised the treatment of influenza with drugs of pinpoint precision.
Using x-ray crystallography, we found a region on one of the surface proteins of the flu virus that does not change in any of its strains.
We teamed up with researchers from the Victorian College of Pharmacy and the Australian National University, and designed a drug called Zanamivir that 'locks' onto this section of the virus and stops the infection progressing.
This approach is now also being used for:
Zanamivir was the first effective drug for treating all strains of the flu, as well as the catalyst for a new class of anti-viral agents called neuraminidase inhibitors.
Australian biotech company Biota sponsored the research and licensed the drug to GlaxoSmithKline.
New drug to fight the flu globally
The drug Zanamivir is commercially available as Relenza and works against all strains of influenza virus including avian and swine flu.
It was brought to the world in 1999 and is now available in 70 countries, marketed by GlaxoSmithKline.
Clinical trials conducted by Glaxo Wellcome in Australia and overseas show that Relenza significantly reduces the duration and severity of flu symptoms, especially if it is taken soon after a person is infected.
More recently, we tested the ability of Relenza to inhibit the H5N1 influenza virus, or bird flu. Flu drugs including Relenza are considered vital for protection against future pandemics such as the H5N1 bird flu.
Neuraminidase inhibitors, such as Relenza, have worldwide annual sales in excess of $3 billion.