Grade 3-4 adverse events seen with a greater than 2 % frequency with tecemotide were dyspnoea ( 49 [ 5 % ] of 1024 patients in the tecemotide group vs 21 [ 4 % ] of 477 patients in the placebo group ) , metastases to central nervous system ( 29 [ 3 % ] vs 6 [ 1 % ] ) , and pneumonia ( 23 [ 2 % ] vs 12 [ 3 % ] ) .