One hundred one patients were randomized in a 1:1 ratio to receive selumetinib , 75 mg orally twice daily on a continual basis ( n = 50 ) , or chemotherapy ( temozolomide , 150 mg/m2 orally daily for 5 of every 28 days , or dacarbazine , 1000 mg/m2 intravenously every 21 days [ investigator choice ] ; n = 51 ) until disease progression , death , intolerable adverse effects , or withdrawal of consent .