EphB4-HSA Fusion Protein and Cytarabine /or Liposomal Vincristine in Patients With Recurrent or Refractory Acute Leukemia

Inclusion Criteria: * Confirmed diagnosis of relapsed or refractory acute leukemia (acute myeloid leukemia, acute lymphoblastic leukemia, blast crisis of chronic myeloid leukemia \[CML\], secondary AML from prior myelodysplastic syndrome \[MDS\] / myeloproliferative neoplasm \[MPN\]); minimum of 5% blasts in the bone marrow or 10% blasts in circulation * Patients with Philadelphia chromosome (Ph)+ ALL or blast crisis of CML must be refractory (not intolerant) to at least 2 second/third generation ABL kinase inhibitors (TKI) * For AML: patients must belong to one of the following ?high risk? categories: * Primary induction failure (PIF) as defined by failure to achieve at least a 50% reduction in bone marrow blasts after one cycle of high intensity, anthracycline containing induction regimen or failure to achieve complete response (CR)/complete remission with incomplete blood count recovery (CRi) after two cycles of high intensity chemotherapy * First early relapse as defined by an initial remission duration of fewer than 6 months * Second or subsequent relapse regardless of remission duration, or * Relapse after allogeneic or autologous stem cell transplantation (first relapse after stem cell transplant would be eligible, regardless of prior duration of remission) * Patients with MDS who transform to AML while on hypomethylator agents or patients with AML who progress on hypomethylator agents could be considered for arm A of this trial if * They choose not to be …