Study Evaluating SKI-606 (Bosutinib) In Philadelphia Chromosome Positive Leukemias

This is an open-label, continuous daily dosing, two-part safety and efficacy study of
SKI-606 (bosutinib) in Philadelphia chromosome positive leukemias (Ph+). Part 1 is a
dose-escalation study in chronic phase Chronic Myelogenous Leukemia (CML) subjects to
establish the maximum tolerated dose (MTD) in this subject population. Part 2 has begun
after the completion of Part 1 and after a dose has been established for the compound in
chronic phase subjects. Part 2 is a study of the the efficacy of 500mg daily oral SKI-606
(bosutinib) in patients with all phases of Ph+ CML and Ph+ Acute Lymphocytic Leukemia (ALL).
The protocol will test the hypotheses that oral daily dosing of bosutinib at 500 mg will
attain (1) Major Cytogenetic Response (MCyR) in chronic phase CML patients and (2) Overall
Hematological Response (OHR) in advanced leukemia patients. Each phase of the disease will
be evaluated as a separate cohort.