PowerMed, a UK biotechnology company, has submitted plans to the Medicines and Healthcare products Regulatory Agency to conduct the first clinical trials for its experimental vaccine against the lethal H5N1 subtype of the avian influenza A virus. Several pharmaceutical companies, including GlaxoSmithKline and Sanofi-Aventis, are also in the race to produce treatments for use in the event of a pandemic.

The PowerMed trial will involve administering the vaccine to volunteers using a needle-free system. Unlike traditional vaccines that incorporate killed or weakened strains or fragments of the virus, this vaccine uses fragments of the H5N1 virus's cDNA to stimulate an immune response. DNA that encodes proteins specific for the H5N1 subtype will be coated onto microscopic gold particles and propelled into the skin at supersonic speed using a helium-powered delivery device.

The production of DNA vaccines is much faster than that of traditional influenza-virus vaccines, in which modified virus is injected into fertilized chicken eggs and allowed to replicate. “We really shouldn't rely on 50-year-old vaccine technology. It's disastrously inefficient,” said John Beadle, chief medical officer at Oxford-based PowerMed (Times Online, 10 July 2006). The H5N1 vaccine can be created in about ten weeks and could be licensed within the next two years (Times Online, 10 July 2006).

PowerMed's vaccine has only been tested in animals so far, where it has been successful. Beadle commented that “... it stops the infection entirely, to the point that we can't even measure the virus in the animals afterwards.” (Guardian Unlimited, 10 July 2006). The purpose of the proposed trials will be to determine the correct dose of vaccine required to produce an immune response in humans and to examine how long the vaccine remains effective.