CHMP accepts GSK's H5N1 vacc for review

UK drug major GlaxoSmithKline says that its next-generation H5N1 split antigen pre-pandemic influenza vaccine has been accepted for review by the European Committee for Medicinal Products for Human Use (CHMP). This vaccine utilizes its novel proprietary adjuvant system technology which allows a very low amount of antigen (3.8mcg) to be used to elicit a strong seroprotective response - the so-called antigen-sparing effect.

In a recent pivotal clinical trial carried out in Belgium involving GSK's novel H5N1 influenza vaccine, the firm noted that 3.8mcg doses of antigen, given 21 days apart, combined with the novel adjuvant system, enabled over 80% of individuals to produce a high seroprotective response, a level which exceeds target criteria set by regulators for the registration of influenza vaccines.

GSK hopes to utilize this antigen-sparing phenomenon to produce a large number of vaccine doses for mass vaccination. 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.