Influenza Vaccine Research & Development

Influenza vaccines have been providing good levels of protection for more than 50 years. Vaccine design has evolved (from whole virus to split and sub-unit), but has not fundamentally changed. However, the performance requirements and use of influenza vaccines have changed significantly over this period:

1) Demand for influenza vaccines has increased several fold in the past five years or so, to more than 400 million  doses annually – a major logistical challenge for industry, bearing in mind that production and distribution have to occur within a limited time period and the vaccine composition changes almost every year.

2) The target groups for seasonal vaccination have been extended beyond the elderly to include at-risk patients (with underlying conditions) of any age, young children and healthy adults requiring protection against influenza. This has not only increased demand, but also highlighted the limitations of currently marketed vaccines in areas such as efficacy and acceptability (often linked to a fear for needles and/or myths toward vaccination).

3) Pandemic awareness and related preparedness activities have increased significantly in the last few years, due particularly to the threat of H5N1. This has further highlighted the limitations of current vaccine design in terms of efficacy and manufacturing scalability – to meet a potential demand that could reach 10 to 20 times the normal seasonal requirement in a pandemic year. Research and Development activities on influenza vaccines are focusing on meeting the above mentioned performance requirements and use of influenza vaccines.