Children 6-11 months ( N = 144 ) and 12-35 months ( N = 186 ) of age received vaccine formulations containing either 3.75 g antigen with half the standard dose of MF59 or 7.5 g antigen with a standard dose of MF59 , or a nonadjuvanted formulation containing 15 g antigen ( children 12-35 months only ) .