Efficacy of a Cell-Culture-Derived Quadrivalent Influenza Vaccine in Children.

Background: Cell-culture-derived influenza vaccines may enable a closer antigenic match to circulating strains of influenza virus by avoiding egg-adapted mutations.

Methods: We evaluated the efficacy of a cell-culture-derived quadrivalent inactivated influenza vaccine (IIV4c) using a Madin-Darby canine kidney cell line in children and adolescents 2 to less than 18 years of age. During three influenza seasons, participants from eight countries were enrolled in an observer-blinded, randomized clinical trial comparing IIV4c with a noninfluenza vaccine (meningococcal ACWY).