Patients in this double-blind study ( n = 539 ) , who had completed 4 induction cycles ( pemetrexed with cisplatin ) without progressive disease ( PD ) and had an ECOG performance status of 0/1 , were randomized 2:1 to pemetrexed maintenance ( 500 mg/m ( 2 ) , day 1 ) plus best supportive care ( BSC ) or placebo plus BSC until PD .