Safety, Pharmacokinetics, and Preliminary Efficacy of BYON4413 in Acute Myeloid Leukemia and Myelodysplastic Neoplasms.

Inclusion Criteria: * Patients who have progressed on standard therapy or have no established alternative treatment, with a diagnosis of: * R/R AML (WHO 2022) OR * MDS (WHO 2022) with ≥10% blasts in BM and have received ≥3 cycles of HMA * Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1 or 2; * Adequate baseline organ function. Exclusion Criteria: * Having been treated with any CD123-targeting therapies; * Having received allogeneic hematopoietic stem cell transplantation within 100 days prior to start Cycle 1 Day 1; * Having treatment-related toxicities from prior anti-leukemia therapies that have not resolved to CTCAE Grade ≤ 1; * Having active central nervous system AML or AML of the APL/M3 subtype; * History of keratitis; * History of specified lung or renal disease; * Having clinically significant cardiovascular disease; * Known infection of Hepatitis B, C or E. Key inclusion and exclusion criteria details are listed here, additional requirements may apply.