PowerMed announced DNA-based bird flu vaccine

Britain's privately owned PowderMed said on Monday it had developed a DNA-based vaccine against bird flu which could be produced quickly and in large quantities in the event of a pandemic.

The British biotech firm's experimental vaccine, which is expected to enter clinical trials by the middle of next year, is further away from the market than rival shots against the H5N1 avian flu strain.

But Chief Executive Clive Dix believes it may have a big advantage because it is not produced laboriously in chicken eggs, like conventional flu shots, and only tiny quantities will be needed to vaccinate large numbers of people.

Industry analysts, however, said the novel DNA-based approach to vaccination was still largely untested and would face scrutiny from healthcare regulators.

"We're probably six months behind but we are in a unique position because we could produce enough vaccine in the first three months of pandemic to vaccinate everybody," he said.

"Just 1.2 kg of vaccine DNA would be sufficient to vaccinate the entire population of the U.S. twice over," reports Reuters.

According to Red Herring, delivery is needle-free. Gold particles coated in the vaccine DNA are propelled into the skin using high-pressure helium. The DNA is translated into protein in the skin’s antigen-presenting cells, prompting an immune response.

Jim Roberts of the United Kingdom’s National Institute for Biological Standards and Control said that PowderMed’s intradermal delivery produces much better immune responses than other efforts to deliver DNA vaccines into muscle.

Another advantage, he said, is that the system requires micrograms of DNA, which are hundredfold to thousand fold smaller amount than other DNA vaccines. However, the relatively complex delivery device may increase the cost of such a vaccine, said Mr. Roberts.

More than 50 people have died from bird flu in south east Asia.

At present H5N1 flu strain poses only a limited threat to humans as it cannot be easily spread from person to person. The cupboard is pretty bare at the moment so it is important these companies develop the vaccines

But experts fear the strain will eventually mutate to acquire this ability, causing a flu pandemic, which could kill as many as 50,000 people in the UK, informs BBC News.