After central testing for EGFR mutations , treatment-naive patients ( stage IIIB or IV cancer [ American Joint Committee on Cancer version 6 ] , performance status 0-1 ) were randomly assigned ( 2:1 ) to receive either oral afatinib ( 40 mg per day ) or intravenous gemcitabine 1000 mg/m ( 2 ) on day 1 and day 8 plus cisplatin 75 mg/m ( 2 ) on day 1 of a 3-week schedule for up to six cycles .