Outcome of Etoposide and Mitoxantrone for Relapsed or Refractory Acute Myeloid Leukemia (RR-AML) in the Modern Era.

e18515 Background: Relapsed or refractory acute myeloid leukemia (RR-AML) carries a poor prognosis, requiring allogeneic transplant for durable remissions. The combination of Mitoxantrone and Etoposide (VP/Mito) is a common regimen utilized to obtain disease control prior to transplant. VP/Mito has been reported in several phase 2 studies, none of which were done in the current era of cytogenetic or gene mutation analysis. Methods: We present a retrospective review of 55 adult patients with RR-AML receiving VP/Mito (Etoposide 100mg/m2 QD x5 days and Mitoxantrone 10mg/m2 QD x5 days) from January 2003 to June 2014. All patients received antimicrobial prophylaxis and most patients received granulocyte-colony stimulating factor support. Results: Baseline characteristics are shown in Table 1. The ORR in patients who received VP/Mito was 31% with a complete response (CR) rate of 20% and CRi rate of 11%. OS and RFS were 5.0 and 5.8 months, respectively. A total of 17 patients (31%) were able to be bridged to an allogeneic HCT. Cytogenetic abnormalities were categorized into AML risk groups by the European LeukemiaNet (ELN) guidelines. Under this stratification, risk groups appeared to correlate with response rates with favorable being 57%, intermediate 42-40% and adverse risk 17%. Primary complications included neutropenic fever (40%), bacteremia (29%), pneumonia (13%), and mucositis (20%). Median duration of neutropenia and thrombocytopenia was 28 and 26 days, respectively. Conclusions: VP/Mito regimen is both a safe and effective therapy for RR-AML, with promising rates in favorable and intermediate risk patients. Efficacy in poor-risk patients is poor and other options should be explored for these patients. Patient characteristics. Total patients, n 55 Median age, years 50 (18-75) Male gender (%) 26 (47%) Prior MDS (%) 9 (16%) Prior # regimens (range) 2 (1-4) Prior regimen 7 + 3 48 (87%) HiDAC 47 (85%) Prior allogenic HCT (%) 11 (20%) ECOG PS, median 1 (0-2) AML risk group, n (%) Favorable 8 (15%) Intermediate I 20 (36%) Intermediate II 5 (9%) Adverse 22 (40%)