The most common adverse events were alanine aminotransferase increases ( 32 [ 8 % ] of 385 patients in the placebo group vs 46 [ 11 % ] of 409 patients in the teriflunomide 7 mg group vs 52 [ 14 % ] of 371 patients in the teriflunomide 14 mg group ) , hair thinning ( 17 [ 4 % ] vs 42 [ 10 % ] vs 50 [ 13 % ] ) , and headache ( 42 [ 11 % ] vs 60 [ 15 % ] vs 46 [ 12 % ] ) .