Clinical Trial

Disease: Acute Myeloid Leukaemia, AML, (NCT04849910)

Disease info:

Leukaemia is cancer of the white blood cells which are responsible for fighting infection. In leukaemia, the bone marrow produces abnormal levels of white blood cells. Acute myeloid leukaemia (AML) starts in the bone marrow but often quickly spreads into the bloodstream. AML sometimes spreads to other parts of the body such as the lymph nodes, liver, central nervous system and testicles. 

Commonly, AML develops from cells other than lymphocytes that would normally develop into white blood cells. The World Health Organization (WHO) divides AML into several subtypes based off genetic association. AML is also known as acute myelocytic leukaemia, acute myelogenous leukaemia, acute granulocytic leukaemia, and acute non-lymphocytic leukaemia.


The American Cancer Society estimates approximately 20,380 cases of AML will be diagnosed in the U.S. in 2023, and approximately 11,310 deaths. AML is predominantly found in adults and is one of the most common types of leukaemia in adults.
Official title:
A First-In-Human, Open-Label, Multicenter Study of VOR33 in Patients With Acute Myeloid Leukemia Who Are at High-Risk for Leukemia Relapse Following Hematopoietic Cell Transplantation

United States, California

University of California San Diego Moores Cancer Center, La Jolla, California, United States, 92037


United States, Florida

Miami Cancer Institute, Miami, Florida, United States, 33176


United States, Missouri

Washington University School of Medicine Siteman Cancer Center, Saint Louis, Missouri, United States, 63110


United States, New Jersey

John Theurer Cancer Center at Hackensack University Medical Center, Hackensack, New Jersey, United States, 07601


United States, New York

Memorial Sloan Kettering Cancer Center, New York, New York, United States, 10065


United States, Ohio

University Hospitals Seidman Cancer Center, Cleveland, Ohio, United States, 44106


United States, Washington

Fred Hutchinson Cancer Research Center, Seattle, Washington, United States, 98109


United States, Maryland

National Institutes of Health, Clinical Center, Bethesda, Maryland, United States, 20892


Canada, Quebec

Hôpital Maisonneuve-Rosemont, Montréal, Quebec, Canada, H1T2M4

Study start:
Dec. 16, 2021
18 participants
Gene editing method:
Type of edit:
Gene knock-out
CD33 molecule
Delivery method:
Undisclosed. - Ex-vivo
VOR33 has been renamed trem-cel
IND Enabling Pre-clinical
Phase I Safety
Phase II Safety and Dosing
Phase III Safety and Efficacy

Status: Active recruiting


This is a Phase 1/2a, multicenter, open-label, first-in-human (FIH) study of VOR33 in participants with AML who are undergoing human leukocyte antigen (HLA)-matched allogeneic haematopoietic cell transplant (HCT).

High risk acute myeloid leukaemia (AML) frequently relapses despite haematopoietic stem cell transplant (HCT). Post-HCT targeted therapy to reduce relapse is limited by toxicity to the engrafted cells. VOR33, an allogeneic CRISPR-Cas9 genome-edited haematopoietic stem and progenitor cell (HSPC) therapy product, lacking the CD33 protein, is being investigated for participants with CD33+ AML at high risk for relapse after HCT to allow post-HCT targeting of residual CD33+ acute AML cells using Mylotarg™ without toxicity to engrafted VOR33 cells. Participants will undergo a myeloablative HCT with matched related or unrelated donor CD34+-selected haematopoietic stem and progenitor cells (HSPCs) engineered to remove CD33 expression (VOR33 product). Mylotarg™ will be given after engraftment for up to 4 cycles. The primary endpoint assessing safety of VOR33 will be the incidence of successful engraftment at 28 days. Part 1 of this study will evaluate the safety of escalating Mylotarg™ dose levels to determine the maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D). Part 2 will expand the number of participants to evaluate the Mylotarg™ RP2D.

Last updated: Apr. 20, 2024
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