Spray may cut need for flu jab

Thu, Feb 19, 2009, 00:00

We may soon have an alternative to the annual flu jab, an easy-to-take mouth spray derived from cow’s milk

THE ANNUAL flu jab may soon be replaced by something a little more palatable – a squirt of a flu-fighting mouth spray.

An Australian company is developing the treatment, which is based on using antibodies produced in cow’s milk after the animals have been inoculated with the virus.

The antibodies are extracted from the colostrum, the first milk a cow produces after calving. About one millilitre of liquid milk is enough for a single dose.

Each cow produces 10 litres or 10,000 single millilitre doses of colostrum per year, which means that, with more than a million cows in Ireland there would be plenty of treatments go around.

It is expected that the spray, called Flubody, will be launched within 18 months, according to Oren Fuerst, spokesman for Immuron, the Australian company developing it.

The flu can be a serious burden on public health, the extent of which depends on the strain. An outbreak of the type that ravaged the globe in 1918 and 1919, for example, could kill tens of millions of people today. Virulent strains like this one are rare, however.

And healthy people are, for the most part, able to fight off the more common, less virulent strains. This however is not necessarily the case for the very young, very old or the sick, which make up about 30 per cent of the population.

Vaccines don’t always work and are of limited use once an infection has taken hold. But scientists at Immuron say that this mouth spray acts immediately and could even stop the disease in its tracks.

‘IT IS APPLIED directly to the respiratory mucosa (the lining of the respiratory tract), where it can prevent infection of cells by the virus. And, perhaps more importantly, it can stop an active infection from spreading from cell to cell, thereby stopping the progress of disease,” according to Fuerst.

“It will be a very useful tool in the face of an outbreak or if you are worried that you have been exposed on an airplane,” he says.

The antibodies are produced by cows that have been exposed to a conventional dead flu vaccine. The vaccine they are given will depend on which flu strain is the most prevalent in that season.

The antibodies produced as a result are naturally expressed in the colostrum and are extracted and freeze dried. “Basically, the cows are doing the heavy lifting of ‘manufacturing’ the antibodies, for you,” Freust says.

This process is 100 times cheaper than current vaccine production methods that involve cloned and highly purified monoclonal antibodies, he says.

The spray has yet to be tested in humans, but trials are planned for this year. Tests in mice infected with the mouse equivalent of avian flu reveal that it is possible to wipe out any trace of the virus.

A single 50 microgram dose reduced the level of infection a hundredfold compared to untreated mice. But a 1,000 microgram dose completely cleared the virus in all animals treated, he indicates.

There are currently no animal-derived medications for flu available in Ireland. And any product like this would certainly have to be put through it paces before it could end up on our shelves.

“Any medications derived from biotechnology or high technology processes would have to be approved via a centralised procedure at the European Medicines Agency,” according to the Irish Medicines Board.

And approval at this level is getting increasingly difficult, given Europeans increasing distrust of biotechnology in general.

THE SPRAY WOULD be suitable for the majority of dairy-intolerant people, as lactose is removed. It is also unlikely that diseases such as BSE could be transmitted by a product like this.

In any event, Freust says the product will only be produced in BSE-free countries.

Immuron already has two products based on bovine antibodies on the market in Australia. They are used in the prevention of diarrhoea.