Dose Escalation Study of JNJ-63709178, a Humanized CD123 x CD3 DuoBody in Participants With Relapsed or Refractory Acute Myeloid Leukemia (AML)

A Phase 1, First-in-Human, Open-Label, Dose Escalation Study of JNJ-63709178, a Humanized CD123 x CD3 DuoBody in Subjects With Relapsed or Refractory AML

The purpose of this study is to characterize the safety and tolerability of JNJ-63709178 and identify the recommended Phase 2 dose(s) (RP2D) and schedule for JNJ-63709178 in Part 1 and to characterize the safety and tolerability of JNJ-63709178 at the RP2D(s) in Part 2.

This is first-in-human (FIH) Phase 1, open-label (identity of assigned study drug will be known), multicenter, dose escalation study with dose expansion to identify the RP2D and to evaluate the safety, tolerability, and preliminary antitumor activity of JNJ-63709178 in adult participants with relapsed or refractory acute myeloid leukemia (AML) who are ineligible for or have exhausted standard therapeutic options. The study will be conducted in 2 parts: dose escalation and dose expansion. The study is divided into 3 periods: a Screening Phase (within 28 days before the first dose of study drug), a Treatment Phase (first dose of study drug until the last dose of study drug) and a Post-treatment Follow-up Phase (up to the end of study participation or end of study). Participants' safety will be monitored throughout the study.

Inclusion Criteria:

• A diagnosis of acute myeloid leukemia (AML) according to the World Health Organization 2008 criteria with relapsed or refractory disease and ineligible for or have exhausted standard therapeutic options
• Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1
• Hematology laboratory parameters within the Protocol specified range
• Chemistry laboratory parameters within the Protocol specified range
• A woman of childbearing potential must have a negative highly sensitive serum (beta human chorionic gonadotropin [b-hCG]) or urine test prior to the first dose of study drug

Exclusion Criteria:

• Acute promyelocytic leukemia
• Active central nervous system involvement
• Prior solid organ transplantation
• Prior hematopoietic stem cell transplant within 6 months of enrollment. If the participant had an allogenic transplant there must be no apparent signs of graft versus host disease and participants must have discontinued all immunosuppressive therapies for at least 4 weeks
• Prior treatment with a CD123xCD3 bispecific agent, T cells expressing CD123 specific chimeric antigen receptor, or toxin-conjugated to CD123 antibodies; prior treatment with naked anti-CD123 monoclonal antibody is permitted