Inclusion Criteria:

- Age >18 years

- Diagnosis of relapsed or refractory AML for which all potentially curative or
standard salvage therapy options have been exhausted; OR AML without prior treatment
who are not eligible for induction chemotherapy as defined as age > or equal to 80 or
age > 70 with poor risk cytogenetics (3 or more abnormalities, -5/del(5q), 3q
abnormalities, or -7) or stable co-morbidities that would preclude induction
chemotherapy such as LVEF less than 40% and/or DlCO less than 60% expected

- ECOG 0-2 performance status

- Biochemical values within the following range

- Serum creatinine <2x upper limit of normal

- Total bilirubin <1.5x upper limit of normal

- AST and ALT <2x upper limit of normal

- Recovery from non-hematologic toxicity from prior chemotherapy

- Able and willing to provide informed consent

Exclusion Criteria:

- Allergy to tetracycline or minocycline

- Uncontrolled intercurrent illness such as uncontrolled diabetes or active
uncontrolled infection

- Active systemic bacterial, fungal, or viral infection

- Concomitant use of linezolid or chloramphenicol that are known to inhibit
mitochondrial protein synthesis

- Pregnant or breast feeding

- Known active CNS involvement with AML

- Neurologic symptoms related to uncontrolled illnesses or unexplained causes

- Psychiatric illness that would limit compliance with study

- Receiving systemic chemotherapy other than hydroxyurea to control circulating blast
counts. Concomitant hydroxyurea is permitted, but only in the first cycle of therapy

- Prior therapy with tigecycline as an anti-cancer therapy or any use of the drug in
the last month

- Use of other investigational anti-leukemic therapy within 14 days of registration