In the priming phase of the trial @ infants were randomised in a @:@:@:@ ratio into four groups to receive either a single MenC-cross reacting material @ ( CRM ) dose at @ months ; two doses of MenC-CRM at @ and @ months ; a single MenC-polysaccharide-tetanus toxoid ( TT ) dose at @ months ; or no MenC doses , respectively .