According to the manufacturer the latest bird flu vaccine is more than 80% effective in protecting people against the virus.
GlaxoSmithkline says it's vaccine which was produced from an inactivated H5N1 virus and a new adjuvant, uses a lower dose of antigen.
When it was used in healthy adult volunteers it produced a stronger seroprotective immune response than expected by regulatory agencies for influenza vaccine registrations.
The trial took place in Belgium and involved 400 healthy adults aged 18-60 and each participant was vaccinated twice during the trial.
Four levels of antigen were tested with 3.8µg being the lowest dose tested.
As many as thirty companies worldwide are racing to produce a vaccine which will offer protection from bird flu and governments are eager to stockpile vaccine in readiness for a potential pandemic.
The challenge has been how to make the maximum number of shots from the minimum amount of antigen, as if a lower dose is needed, more people can be given the shot.
Antigen is produced in chicken eggs and is a lengthy and arduous process; it boosts the vaccine's effectiveness and makes it more powerful.
GlaxoSmithkline is Europe's biggest pharmaceutical company and says is on track to start manufacturing by the end of 2006 and if approval is granted could mass produce the vaccine in 2007.
The company says the results represent a significant breakthrough and is the first time such a low dose of H5N1 antigen has been able to stimulate such a level of strong immune response.