Inclusion Criteria:

- Acute myeloid leukemia diagnosed according to WHO criteria with one of the following:

- Primary refractory disease following ≥ 1 round of induction chemotherapy

- First relapse or higher

- Age between 18 and 70 years

- ECOG performance status ≤ 2

- Adequate organ function defined as:

- Creatinine ≤ 1.5 x institutional ULN

- AST ≤ 2 x ULN except when in the opinion of treating physician is due to direct
involvement of leukemia (e.g., hepatic infiltration or biliary obstruction due
to leukemia)

- ALT ≤ 2 x ULN except when in the opinion of treating physician is due to direct
involvement of leukemia (e.g., hepatic infiltration or biliary obstruction due
to leukemia)

- Total bilirubin ≤ 2 x ULN except when in the opinion of treating physician is
due to direct involvement of leukemia (e.g., hepatic infiltration or biliary
obstruction due to leukemia)

- Left ventricular ejection fraction of ≥ 40% by MUGA scan or echocardiogram

- Women of childbearing potential and sexually active males must be willing and able to
use effective contraception while on study

- Able to provide signed informed consent prior to registration on study

Exclusion Criteria:

- Acute promyelocytic leukemia (AML with t(15;17)(q22;q11) and variants)

- Peripheral blood blast count ≥ 50 x 103 /mm3

- Active CNS involvement with leukemia

- Previous treatment with MEC or other regimen containing both mitoxantrone and
etoposide

- Pregnant or nursing

- Concurrently receiving any other investigational agent

- Received colony stimulating factors filgrastim or sargramostim within 48 hours or
pegfilgrastim within 14 days of study

- Less than 2 weeks from the completion of any previous cytotoxic chemotherapy
(excluding hydroxyurea)

- Severe concurrent illness that would limit compliance with study requirements