Complete molecular remission in relapsed and refractory acute myeloid leukaemia with MLL-AF9 treated with chidamide-based chemotherapy

What is known and objectiveThe mixed lineage leukaemia (MLL) gene translocations are found in approximately 10% of adults with acute myeloid leukaemia (AML) and are markers of poor prognosis. As the best reported response in relapsed and refractory MLL-rearranged AML is around 40%, reinduction treatment is very challenging for those patients. Case descriptionWe report a case of relapsed and refractory AML with MLL-AF9, who did not respond to FLAG (fludarabine, cytarabine, granulocyte colony stimulating factor) regimen reinduction treatment, but achieved complete response and molecular remission after chidamide-based chemotherapy. What is new and conclusionChidamide (CS055/HBI-8000) is a new histone deacetylase (HDAC) inhibitor that is clinically active in relapsed and refractory peripheral T-cell lymphomas. To the best of our knowledge, successful reinduction treatment on relapsed MLL-AF9 by chidamide-based regimen has not been previously reported.