Alternative first-line treatments of acute ATLL include the combination of INF-α with AZT, an antiretroviral agent, based upon phase II studies.15 In relapsed/refractory disease, mogamulizumab and lenalidomide have limited clinical activity with median progression free survival (mPFS) of 4–5 months.16,17. Here, IFNA17 is linked to adult T-cell leukemia/lymphoma.