Genetic Ablation of CD33 in HSC to Broaden the Therapeutic Index of CD33-directed Immunotherapy in Patients With AML — GALAXY33  

Relapsed/Refractory Acute Myeloid Leukemia (AML) Clinical Trial

Official title: Genetic Ablation of CD33 in Hematopoietic Stem Cells to Broaden the Therapeutic Index of CD33-directed Immunotherapy in Patients With Acute Myeloid Leukemia (AML)

Status Not yet recruiting

Clinical Trial Summary

The study "GALAXY33" is an open-label, prospective, nonrandomized, one arm phase I clinical trial in which patients with relapsed AML after allogeneic hematopoietic stem cell transplantation will be transplanted with CD33-deleted CD34+ HSC derived from the initially matched family donor.

Clinical Trial Description

CRISPR/Cas9-mediated inactivation of CD33 in hematopoietic stem cells (HSC) may broaden the therapeutic index of CD33-directed immunotherapy for patients with AML by rendering healthy hematopoietic stem and progenitor cells (HSPC) resistant to escalating doses and/or shorter dosing intervals of the CD33-specific antibody-drug conjugate (ADC) Gemtuzumab-ozogamicin (GO).

In this proof of concept trial, we will develop a platform for genome editing of CD34+ HSC and demonstrate the feasibility, safety and efficacy of this approach for targeted therapy of AML.

Upon implementation, the platform shall be used for innovative clinical trials in diverse types of cancer. Outside of leukemias, autologous HSC could be used to ease the procedure.

Patients with relapsed AML after allogeneic hematopoietic stem cell transplantation will be transplanted with CD33-deleted CD34+ HSC derived from the initially matched family donor.

Upon HSC engraftment, patients will be treated with escalating doses of the anti-CD33 antibodydrug conjugate Gemtuzumab-Ozogamicin (GO). A conditioning regimen containing GO (d-14, d-11, d-8),Fludarabine 30 mg/m2 (d-6 to d-3) and Melphalan 140mg/m2 (d-2) is used prior to transplantation.

The clinical trial will be conducted at two trial sites in the University Hospitals in Heidelberg and Dresden.

25 patients will be assessed for eligibility and 12 patients will be allocated into the trial. ;

Related Conditions & MeSH terms

• Leukemia
• Leukemia, Myeloid
• Leukemia, Myeloid, Acute
• Relapsed/Refractory Acute Myeloid Leukemia (AML)

• NCT number: NCT05662904
• Study type: Interventional
• Source: German Cancer Research Center
• Contact: Tim Sauer, Dr. med.
• Phone: +49 6221 56 38010
• Email: tim.sauer@med.uni-heidelberg.de
• Status: Not yet recruiting
• Phase: Phase 1
• Start date: December 2023
• Completion date: February 2025