Defects in the apoptotic process can lead to the onset of cancer by allowing cells to grow unchecked when an oncogeneic signal is present. Obatoclax is designed to restore apoptosis through inhibition of the Bcl-2 family of proteins, thereby reinstating the natural process of cell death that is often inhibited in cancer cells.

This is a multi-center, open-label, Phase II study of obatoclax administered in 2-week cycles to patients with previously-untreated Myelodysplastic Syndromes with anemia and/or thrombocytopenia. Treatment may be administered on an outpatient basis. No investigational or commercial agents or therapies other than those described herein may be administered with the intent to treat the patient's malignancy. Supportive care measures including those directed at controlling symptoms resulting from Myelodysplastic Syndromes are allowed

Inclusion Criteria:

• Pathological confirmation of Myelodysplastic Syndromes (MDS)
• Patients must have had no prior systemic therapy
• Must have normal organ functions
• Must have the ability to understand and willingness to sign a written informed consent form

Exclusion Criteria:

• Must not be a result of prior chemotherapy and/or radiotherapy for another malignancy
• No other agents or therapies administered in the intent to treat
• Uncontrolled, intercurrent illness
• Pregnant women and women who are breast feeding