Tolerability and PK/PD of Multiple Oral Doses of CT53518 in Patients With Acute Myelogenous Leukemia

Inclusion Criteria:

Each patient must meet the following inclusion criteria to be eligible to participate in
the study.

- Men and women who are over 18 years of age and have one of the following conditions:

- AML with relapse within 12 months of the completion of consolidation therapy who
are not to receive gemtuzumab-ozogamicin; or

- AML with relapse after 12 months of the completion of consolidation therapy for
whom, in the opinion of the investigator, the risk of alternative therapy
outweighs the possible benefit; or

- newly diagnosed AML refractory to conventional remission-induction chemotherapy
("refractory" is defined as >10% blasts in blood and/or bone marrow upon
recovery from two cycles of standard cytarabine-based induction chemotherapy);
or

- newly diagnosed, or previously treated AML, greater than 60 years of age and not
or no longer a candidate for conventional remission-induction chemotherapy or
gemtuzumab-ozogamicin

- No reproductive potential (surgically, post- menopausal, or using two methods of
contraception)

- Demonstrated FLT-3 gene, internal tandem duplication mutation

- ECOG performance status of 0 to 2

- Has not received cytoreductive drug therapy for at least 4 weeks, and has not
received hydroxyurea within 24 hours prior to first dose of the study drug

- Has not received a bone marrow transplant or peripheral blood stem cell transplant
within the last two months

- Able to read and give written informed consent and has signed a consent form approved
by the Investigator's Institutional Review Board (IRB)

Exclusion Criteria:

Patients meeting any of the following criteria are not eligible to participate in the
study:

- Participated in an investigational drug study in the last 30 days

- Serum Creatinine >2 mg/dL

- Evidence of a clinically significant liver disease by history, physical examination
and/or laboratory data (e.g. transaminases exceeding 3 x ULN and/or total bilirubin >
2 mg/dL

- Known to have used illicit drugs within the last 30 days

- Has an uncontrolled active infection

- Pregnant or nursing mother

- Candidate for conventional chemotherapy (except hydroxyurea), including growth
factors or hormonal therapy for cancer

- Any concomitant disease or condition which could interfere with or for which the
treatment might interfere with the conduct of the study the, or which would, in the
opinion of the Investigator and/or Sponsor, increase the risk of the patient's
participation in the study. This includes but is not limited to alcoholism, drug
dependency or abuse, psychiatric disease.