Proteinaceous meningococcal B vaccines are under development, and the most 
advanced, Bexsero, is currently being evaluated by the European Medicines 
Agency. Approval, if granted, will be based on safety, immunogenicity, and 
theoretical strain coverage established in vitro. Clinical effectiveness will 
only be determined after market release. New, more effective influenza vaccines 
are also being developed. A trivalent attenuated nasal influenza vaccine 
(Fluenz) shows better efficacy in children than the classic trivalent seasonal 
inactivated vaccine, but its use is restricted to children over 2 years of age 
because of safety and efficacy considerations. The more potent trivalent (MF59) 
adjuvated inactivated influenza vaccine (Fluad), licensed for adults over 65 
years of age, is being evaluated through a pediatric investigation plan. This 
vaccine could be useful for infants in whom unadjuvated inactivated vaccines are 
poorly protective, but its safety must first be fully established.