Following treatment with both fostamatinib regimens , a statistically significant difference in the ACR20 improvement response was achieved at week 24 as compared with that in patients receiving placebo ( 49.0 % [ group A ] and 44.4 % , [ group B ] versus 34.2 % ; P < 0.001 and P = 0.006 , respectively ) , but there was no statistically significant difference in the SHS between either fostamatinib group and placebo ( P = 0.25 and P = 0.17 , respectively ) .