A Study of FF-10501-01 in Combination with Azacitidine in Patients with Myelodysplastic Syndrome

Inclusion Criteria: 1. Male or female patients ≥ 18 years of age 2. MDS as determined by bone marrow aspirate and/or biopsy according to the WHO Classification within 6 weeks of the first dose of study medication, with bone marrow blast counts of \< 20%. 3. Int2/High-risk MDS according to the IPSS, Intermediate/high/very high-risk MDS according to the IPSS-R, or otherwise eligible for treatment with azacitidine in the judgment of the Investigator 4. ECOG Performance Score of 0 or 1 5. Adequate hepatic function as evidenced by AST/ALT \< 3X the ULN and total bilirubin \< 2X the ULN for the reference lab 6. Adequate renal function as evidenced by serum creatinine \< 2 mg/dL or a calculated creatinine clearance of \> 50 mL/min Exclusion Criteria: 1. A current infection requiring treatment with intravenous antibiotics, anti-fungal agents, or anti-viral agents 2. Previous treatment with a hypomethylating agent, an HDAC inhibitor, or any other drug intended for the treatment of MDS other than hematopoietic growth factors, immunosuppressive therapy or hydroxyurea. Patients with 5q deletions may have received prior lenalidomide. 3. Use of hematopoietic growth factors (erythropoietin, G-CSF, GM-CSF, thrombopoietin receptor agonists) or immunosuppressive treatments within 7 days of first dose of study medication 4. Administration of any investigational agent within 5 half-lives of the agent; if the half-life is not known, use of such an agent within 2 weeks of the first dose of study medication 5. Active infection with HIV or hepatitis B or C; patients with a history of such disorders should undergo serological testing to evaluate the activity of the infection