Inclusion Criteria

Inclusion Criteria

- Must have a histologically documented relapsed/refractory AML for which there is no
standard therapy that has been demonstrated to have curative or palliative potential.

- ECOG performance status of 0-2.

- Must be 18 years or older.

- Estimated life expectancy > 1 month.

- Laboratory data:

- total bilirubin ≤ 1.5 x upper limit of normal unless due to Gilbert's syndrome

- serum creatinine ≤ 2.0 mg/dl

- AST ≤ 3.0 x upper limit of normal

- Cardiac ejection fraction > 40%

- FEV1.0 > 50% predicted

- Prior therapy: > 3 weeks since chemotherapy, biological therapy or radiation;
anticipated maximum hematological improvement since last dose of chemotherapy.
(Concurrent hydroxyurea administration will be allowed to control WBC count, platelet
count, or symptoms).

- No active infections.

- Negative pregnancy test for women of childbearing potential.

- No uncontrolled psychiatric illness or medical illness that the principal
investigator feels will compromise the patient's tolerance of the study medication.

- Must provide informed consent.

Exclusion Criteria

- Patients with an allergy to proton pump inhibitors, required for GI prophylaxis; or
salicylates are excluded.

- Pregnant or lactating women

- Age <18 years. Because no dosing or adverse event data are currently available on the
use of TPA alone or in combination with dexamethasone in patients < 18 years of age,
children are excluded from this study but will be eligible for future pediatric Phase
II combination trials.

- The effects of TPA on the developing human fetus are unknown. For this reason, women
of childbearing potential and men must agree to use adequate contraception (hormonal
or barrier method of birth control; abstinence) prior to study entry, for the
duration of study participation and for 10 weeks after. Should a woman become
pregnant or suspect she is pregnant while participating in this study, she should
inform her treating physician immediately. Should the female partner of a participant
in this study become pregnant or suspect she is pregnant during this study, the PI of
this study will be available to provide advice about further medical/obstetric
care/referral for the female partner.

- Patients with active CNS involvement (documented by radiographic lesions and/or
malignant cells in the CSF) will be excluded from this clinical trial because of
their poor prognosis and because they often develop progressive neurologic
dysfunction that would confound the evaluation of neurologic and other adverse
events.

- Patients with treatment of any other investigational drug within the last 30 days
prior to entering the study.