Grade 3-4 neutropenia ( 114 [ 22 % ] for lenalidomide vs 85 [ 16 % ] for placebo ) , febrile neutropenia ( 62 [ 12 % ] vs 23 [ 4 % ] ) , diarrhoea ( 37 [ 7 % ] vs 12 [ 2 % ] ) , pneumonia ( 24 [ 5 % ] vs five [ 1 % ] ) , dyspnoea ( 22 [ 4 % ] vs nine [ 2 % ] ) , asthenia ( 27 [ 5 % ] vs 17 [ 3 % ] ) , and pulmonary embolism ( 32 [ 6 % ] vs seven [ 1 % ] ) occurred more frequently in the lenalidomide group than in the placebo group .