GlaxoSmithKline has presented data from two new studies which show that its candidate pre-pandemic H5N1 vaccine, could protect against different strains of the avian flu virus.

The data was presented at the ninth International Symposium on Respiratory Viral Infections and the first study, comprising 400 people, demonstrated that GSK's pre-pandemic vaccine, which contains very low levels of the Vietnam H5N1 antigen (3.8 micrograms), elicits a strong cross-immune neutralising antibody response in humans against the Indonesian strain of the virus.

The firm added that the neutralising antibody seroconversion factor at day 42 was shown to be 25 times greater when the vaccine contained the adjuvant system compared with that observed in the control group immunised with a non-adjuvanted vaccine.

The second study showed that the vaccine could protect against two diverse H5N1 flu strains, again at very low levels of antigen, and GSK said that the results are “giving an additional boost to hopes that pre-pandemic vaccination is a viable strategy for inclusion in pandemic preparedness plans.”

GSK announced in January that it had landed a $63.3 million contract from the US Department of Health and Human Services to develop H5N1 pandemic flu vaccines and the company’s product is currently under review at European Medicines Agency. David Stout, president of GSK Pharmaceuticals, added that “we believe this vaccine will provide governments with a new option to help protect their populations against the threat of a future human influenza pandemic.”