Refractory Mixed Phenotype Acute Leukemia

This phase II trial tests the safety and best dose of revumenib in combination with chemotherapy, and evaluates whether this treatment improves the outcome in infants and young children who have leukemia that has come back (relapsed) or does not respond to treatment (refractory) and is associated with a KMT2A (MLL) gene rearrangement (KMT2A-R). Leukemia is a cancer of the white blood cells, where too many underdeveloped (abnormal) white blood cells, called "blasts", are found in the bone marrow, which is the soft, spongy center of the bones that produces the three major blood cells: white blood cells to fight infection; red blood cells that carry oxygen; and platelets that help blood clot and stop bleeding. The blasts crowd out the normal blood cells in the bone marrow and spread to the blood. They can also spread to the brain, spinal cord, and/or other organs of the body. The leukemia cells of some children have a genetic change in which a gene (KMT2A) is broken and combined with other genes that typically do not interact with one another; this is called "rearranged". This genetic rearrangement alters how other genes are turned on or off in the cell, turning on genes that drive the development of leukemia. Patients with KMT2A rearrangement have higher risk for cancer coming back after treatment. Revumenib is an oral medicine that directly targets the changes that occur in a cell with a KMT2A rearrangement and has been shown to specifically kill these leukemia cells in preclinical laboratory settings and in animals. Drugs used in chemotherapy, such as vincristine, prednisone, asparaginase, fludarabine and cytarabine work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. This trial is being done to find out if the combination of revumenib and chemotherapy would be safe and/or effective in treating infants and young children with relapsed or refractory KMT2A-R leukemia.

This phase I trial tests the safety, side effects, and best dose of uproleselan in combination with fludarabine and cytarabine in treating patients with acute myeloid leukemia, myelodysplastic syndrome or mixed phenotype acute leukemia that has come back (relapsed) or does not respond to treatment (refractory) and that expresses E-selectin ligand on the cell membrane. Uproleselan binds to E-selectin expressed on endothelial cells of the bone marrow and prevents their interaction with selectin-E ligand-expressing cancer cells. This may prevent leukemia cells from being sequestered in the bone marrow niche and escaping the effect of chemotherapy. Chemotherapy drugs, such as fludarabine and cytarabine, work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Giving uproleselan in combination with fludarabine and cytarabine may enhance their activity.

This phase I/II trial finds the highest safe dose of IMGN632 that can be given with other chemotherapy without causing severe side effects, studies what kind of side effects IMGN632 may cause, and determines whether IMGN632 is a beneficial treatment for leukemia in children that has come back after treatment or is difficult to treat. IMGN632 is a monoclonal antibody linked to a chemotherapy drug. IMGN632 is a form of targeted therapy because it attaches to specific molecules (receptors) on the surface of cancer cells, known as CD123 receptors, and delivers the chemotherapy drug to kill them. Giving IMGN632 with other chemotherapy may cause the leukemia to stop growing or to shrink for a period of time.