Summary

This study evaluates ADCT-301 in participants with Acute Myeloid Leukemia (AML) or Acute Lymphoblastic Leukemia (ALL). Participants will participate in a dose-escalation phase (Part 1) and receive ADCT-301 either weekly or once every 3 weeks. In Part 2 of the study, participants will receive a recommended dose of ADCT-301 as determined by a Dose Escalation Steering Committee.

Objectives

This is a Phase 1 study with ADCT-301 to evaluate the safety, tolerability and pharmacokinetics of ADCT-301 in participants with Acute Myeloid Leukemia (AML) or Acute Lymphoblastic Leukemia (ALL). ADCT-301 is a human monoclonal antibody attached via a cleavable linker to a pyrrolobenzodiazepine (PBD) warhead which, when internalized by antigen expressing cells, covalently cross links deoxyribonucleic acid (DNA) preventing replication. The study will be conducted in 2 parts: In Part 1 (dose escalation) participants will either be on weekly administration or every 3-week administration. Participants on weekly administration will receive an infusion of ADCT-301 on Days 1, 8, and 15 of each 3 week treatment cycle. Participants on 3-week administration will receive an infusion of ADCT-301 on Day 1, every 3 weeks. Dose escalation will continue until the maximum tolerated dose (MTD) is determined. In Part 2 (expansion), participants will be assigned to receive a recommended dose and/or schedule of ADCT-301 as determined by a Dose Escalation Steering Committee. For each participant, the study will include a screening period (up to 28 days), a treatment period, and a follow-up period to assess disease progression and survival for up to 12 months after the last dose of study drug. The total study duration will be dependent on overall participant tolerability to the study drug and response to treatment. It is anticipated that the entire study (Parts 1 and 2) will enroll a maximum of 80 participants and could last approximately 3 years from first participant treated to last participant completed.