The EMEA is racing to fast-track the review of data on H1N1 pandemic vaccines before the start of the Northern hemisphere flu season, which is expected to begin in September. According to the World Health Organization (WHO), more than 130000 people worldwide have already been affected by the pandemic H1N1 influenza strain. In a briefing note on its website, WHO also stated: "The number of human cases of pandemic (H1N1) 2009 is still increasing substantially in many countries, even in countries that have already been affected for some time."
Several pandemic vaccines are under development, and preliminary data from GlaxoSmithKline (GSK) and Sanofi Pasteur are already being under accelerated assessment by the Committee for Medicinal Products for Human Use (CHMP). Four mock-up vaccines — made using the similar H5N1 strain of influenza — from Baxter, GSK and Novartis have also been granted marketing authorization in the EU.
All the manufacturers will be applying for a variation to the marketing authorization by including the new strain in the vaccines. The first of these could be submitted in September 2009 and the agency believes that the application will be processed quickly — possibly within five days. CHMP also believes that the variation will not have a major impact on the safety and efficacy of the final vaccine.
Meanwhile, WHO says that the yields for the vaccine seed strain are continuing to improve thanks to the development of new candidate vaccine viruses by the WHO network. Other important information will also be gathered from ongoing or soon-to-begin clinical trials that will shed light on dosing.