Optaflu has gained European approval for use against seasonal influenza.

The Novartis drug is the first flu vaccine which does not rely on chicken eggs for the production of viral antigen components, leading the company to hail it as  the first major innovation in influenza vaccine manufacturing in more than 50 years. With virus experts suggesting a flu pandemic is a question of 'when' rather than 'if', it is a potential blockbuster.

Novartis says its new technology means Optaflu, administered via intramuscular injection, can be manufactured more quickly than other vaccines, offering the potential to respond to an outbreak swiftly. And the worldwide increase of cases of avian flu A/H5N1 - highly contagious in chickens - has raised the possibility of a pandemic emerging at a time when egg supplies are potentially lower than usual. The World Health Organisation currently ranks the H5N1 pandemic risk at phase three on a scale of one to six.

Jorg Reinhardt, CEO of Novartis Vaccines and Diagnostics, said the alternative to traditional egg-derived vaccines "would provide for a more flexible and reliable production process, so as to contribute to meet the ongoing need for seasonal influenza vaccines and the potential need for influenza vaccines in the event of a pandemic".

Novartis says its proprietary cell culture technology means it may also be possible to match the vaccine more effectively with circulating viruses than is currently the case. Vaccine seed strain development may be closer to the original 'wild' virus because it does not need to pass through eggs - where the virus may be forced to adapt in order to replicate.

Phase III data was presented at the Influenza Vaccines for the World Congress meeting last October and at Options for the Control of Influenza VI Conference in Toronto this month.

Up against brands such as Roche's Tamiflu and GlaxoSmithKline's Relenza, Optaflu is expected to be available in Germany and Austria this winter and in remaining EU countries a year later. US regulatory approval will be sought in 2008. The drug has received approval in all 27 European Union states, as well as Iceland and Norway.

Flu epidemics kill between 250,000 and 500,000 people worldwide each year. Less serious complications include pneumonia and dehydration plus the worsening of chronic conditions, such as heart failure, asthma, or diabetes.

pharmafocus@wiley.co.uk