At week 24 , estimated mean ( 95 % CI ) changes in LDL-C from baseline were -48.2 % ( -52.0 % to -44.4 % ) and -2.3 % ( -7.6 % to 3.1 % ) for alirocumab and placebo , respectively , an estimated mean ( 95 % CI ) difference of -45.9 % ( -52.5 % to -39.3 % ) ( P < .0001 ) .