Grade 3/4 adverse events were 36 % versus 31 % ( P = 0.624 ) ; the most frequent G3/4 toxicities were vomiting ( 5.8 % saracatinib versus 8.6 % placebo ) , abdominal pain ( 5.8 % versus 0 % ) and diarrhoea ( 4.3 % versus 5.7 % ) .