The median DOR for romidepsin in the pivotal study of PTCL was 28 months, with no significant difference in DOR across the three most common PTCL subtypes (PTCL‐NOS, AITL, and ALK− ALCL), and the longest response ongoing at 56 months in a patient with AITL 15, 34. Here, ALK is linked to anaplastic large cell lymphoma.