Following randomisation patients will receive Arm A : AZD2014 plus anastrozole or Arm B: anastrozole alone AZD2014 will be administered with an intermittent schedule i.e. 125 mg bis in die (BID) intermittent with 2 days on followed by 5 days off per week for a total weekly dose of 500 mg/week (250mg D1 and D2, 5 days off) Anastrozole will be administered at the standard dose defined in the SPC i.e. 1mg/d, per os, continuously.