GlaxoSmithKline (GSK) has announced that the Committee for Medicinal Products has accepted its new generation H5N1 split antigen pre-pandemic influenza vaccine for review for Human Use (CHMP) in Europe. This innovative vaccine utilises GSK's novel proprietary adjuvant system technology, which allows a very low amount of antigen (3.8µg) to be used to elicit a strong seroprotective response - the so-called 'antigen-sparing' effect.
In a recent pivotal clinical trial carried out in Belgium1 involving the new generation H5N1 influenza vaccine, it was shown that two very low doses of antigen (3.8µg), given 21 days apart, combined with the novel adjuvant system enabled over 80 per cent of individuals to produce a high seroprotective response, a level which exceeds target criteria set by regulatory authorities for registration of influenza vaccines.
This 'antigen-sparing' phenomenon permits a large number of vaccine doses to be produced for mass vaccination ensuring protection for more people. Furthermore, the magnitude of the immune response to the antigen, in the presence of the novel adjuvant system, is also expected to give protection against 'drifted' variants of the H5N1 virus. The vaccine also had an acceptable safety and reactogenicity profile.
Jean Stéphenne, president of GSK Biologicals, the vaccine division of GSK, commented: "Today's filing of our new generation pre-pandemic influenza vaccine marks another important milestone in our pandemic preparedness vaccine development programme. I believe the rapidity with which immunogenicity and safety data has been generated resulting in this filing, pays tribute to our ongoing commitment to provide, in as short a timeframe as possible, credible options against the threat of an influenza pandemic."
"As our new generation pre-pandemic influenza vaccine is also believed to have the potential to offer a cross-protective response the vaccine could be used as part of a proactive pre-pandemic vaccination campaign, giving governments and health authorities the option to initiate vaccination before or at the onset of a pandemic and potentially offering a degree of early protection against the pandemic influenza virus," added Jean Stéphenne.
GSK are also planning to file the pre-pandemic vaccine in other countries around the world. This new generation vaccine could also be adapted for pandemic use once the causative influenza pandemic strain is identified. Indeed, GSK has already entered into active negotiations with various governments to supply pre-pandemic and/or pandemic influenza vaccines. GSK are also planning to file the pre-pandemic vaccine in other countries around the world subsequently.