(CIDRAP News) In an effort to overcome the difficult problem of predicting which influenza B strain will circulate in any given season, MedImmune has filed for US approval of a quadrivalent (four-strain) flu vaccine containing two influenza B strains.
The idea of a quadrivalent flu vaccine has been discussed for several years, but MedImmune's application apparently is the first attempt to license such a vaccine in the United States.