In the patients who received previous concurrent chemoradiotherapy , median overall survival for the 538 ( 65 % ) of 829 patients assigned to tecemotide was 30.8 months ( 95 % CI 25.6-36 .8 ) compared with 20.6 months ( 17.4-23 .9 ) for the 268 ( 65 % ) of 410 patients assigned to placebo ( adjusted HR 0.78 , 0.64-0 .95 ; p = 0.016 ) .