A Phase 1 Study of AMV564 in Patients With Intermediate or High-Risk Myelodysplastic Syndromes

Inclusion Criteria: * ≥ 18 years of age * Diagnosis of MDS according to WHO 2016 criteria * ECOG performance status of 0 or 1 * Intermediate-2 or high-risk disease per IPSS * Fewer than 20% blasts in the bone marrow or peripheral blood * Disease that is refractory to or relapsed from either a hypomethylating agent (e.g. decitabine or azacitidine) or a standard AML-type intensive regimen * Adequate organ function * Prior allogeneic transplant performed ≥ 3 months prior to first dose of AMV564 is allowed provided there is no evidence of active graft-versus-host disease (GVHD) and the patient has been off immunosuppressive therapy for ≥ 4 weeks. Exclusion Criteria: * History of, or known, central nervous system (CNS) disease involvement, or prior history of National Cancer Institute (NCI) Common Toxicity Criteria for Adverse Events (CTCAE) Grade ≥ 3 drug-related CNS toxicity * Prior allogeneic transplant if performed \< 3 months prior to first dose of AMV564, if patient has active GVHD, or if patient has not been off immunosuppressive * Prior treatment with a therapeutic agent targeting CD33 (e.g. gemtuzumab ozogamicin, SGN-CD33A or AMG 330).