Outcome of elderly patients after failure to hypomethylating agents given as frontline therapy for acute myeloid leukemia: Single institution experience*

Outcomes of acute myeloid leukemia (AML) in elderly patients unfit for intensive chemotherapy is challenging. Hypomethylating agents (HMAs) can be effective in these patients but responses are usually short-lived. The majority of patients will either have stable disease or progress through therapy. We hereby describe the outcome of these patients at our institution after they fail HMAs. The data on 56 AML patients at Mayo Clinic, Rochester were reviewed. Patients were considered for our study if they received HMA as frontline therapy for their AML. Out of 56 patients, 15 (27%) patients received azacitidine (AZA) and 41 (73%) received decitabine. Complete remission was found in 10 (18%), with overall response of 28% and median response duration of 10 months. Thirteen (81%) out of 16 responders relapsed. Therefore 53 patients were included in the primary or secondary failure analysis with a median overall survival (OS) of 2 months after the date of failure. Out of 53 patients, 12 (23%) received subsequent treatments. None of the 12 patients who got first salvage therapy achieved remission. Five out of the 12 patients received second salvage therapy, 2 (40%) of which achieved CR. Median OS for patients who received subsequent salvage therapies was better than those who did not receive any subsequent therapy after failing HMA (9.5 vs. 2 months, P =.0009). Outcome for patients who have primary or secondary failure is very poor. Our study provides important historical data for future novel therapies, which are sorely needed for these patients.