Least-square mean spleen volume decreased by 27.77 % ( 95 % CI , -32.57 % to -22.97 % ) in the eliglustat group ( from 13.89 to 10.17 multiples of normal ) vs an increase of 2.26 % ( 95 % CI , -2.54 % to 7.06 % ) in the placebo group ( from 12.50 to 12.84 multiples of normal ) for an absolute treatment difference of -30.03 % ( 95 % CI , -36.82 % to -23.24 % ; P < .001 ) .