Study of a Novel BET Inhibitor FT-1101 in Patients With Relapsed or Refractory Hematologic Malignancies

Key Inclusion Criteria: * Single agent (SA) Dose Escalation: Histologically or cytologically proven acute leukemia or high-risk MDS as defined by the World Health Organization (WHO) criteria and IPSS-R, respectively, that is relapsed or refractory (R/R) to standard therapy or for whom standard treatments are contraindicated, OR * Mature B-Cell non-Hodgkin Lymphoma that is Relapsed/Refractory to standard therapy * AML SA expansion group 1: histologically or cytologically proven AML with a FLT3 ITD or TKD mutation previously determined by local testing that is R/R to standard therapy or for whom standard treatments are contraindicated * AML SA expansion group 2: histologically or cytologically proven AML with intermediate or unfavorable risk cytogenetics in the absence of a detectable FLT3 ITD or TKD mutation as previously determined by local testing that is R/R to standard therapy or for whom standard treatments are contraindicated * NHL SA expansion: Mature B-cell NHL with the following histologies: primary mediastinal lymphoma, DLBCL, and B-cell lymphoma not specified that is R/R to standard therapy and for whom standard treatments are contraindicated or unavailable * AML/MDS combination treatment (dose escalation and expansion): histologically or cytologically proven AML or MDS as defined by WHO criteria and IPSS-R, respectively, that is: R/R to standard therapy, or AML: who are unfit for, or unwilling to receive standard induction therapy, or MDS: eligible to receive azacitidine * Patients ≥ 18 years old * Good kidney and liver function * No prior organ allograft * For fertile men and women, agreement to use effective contraceptive methods duration of study participation and 90 days after Key Exclusion Criteria: * History of prior malignancy unless disease free for \> or equal to 12 months or considered surgically cured. * Patients with symptomatic central nervous system (CNS) metastases or other tumor location (such as spinal cord compression, other compressive mass, uncontrolled painful lesion, bone fracture, etc.) necessitating an urgent therapeutic intervention, palliative care, surgery or radiation therapy * Treatment with major surgery (requiring general anesthesia) within one month prior to study entry * Previous treatment with any prior BET inhibitor therapy * Patients unable to swallow oral medications, or patients with gastrointestinal conditions (e.g. malabsorption, gastric or small bowel resection, etc.) deemed to jeopardize intestinal absorption * Congestive heart failure (New York Heart Association Class III or IV) or unstable angina pectoris. Previous history of myocardial infarction within 1 year prior to study entry, uncontrolled hypertension or uncontrolled arrhythmias * Pulmonary disease (e.g. COPD, asthma, etc) that is not controlled (moderate to severe symptoms) with current medication * Known HIV positivity * Active, uncontrolled bacterial, viral, or fungal infections, requiring systemic therapy