KMT2A rearrangements—a DNA fault—lead to treatment-resistant acute lymphoblastic leukemia (ALL) in infants. While around 50% of children with KMT2A rearrangements respond well to intensive chemotherapy, the remaining 50% do not. In those who respond poorly to chemotherapy treatment, this cancer typically recurs within two years. KMT2A rearrangements, then, are associated with poor outcomes. Serving these infants means finding new and effective treatment measures—such as immunotherapy using blinatumomab. 

Blinatumomab is a bispecific CD19-directed CD3 T-cell engager that binds to CD19 and CD3, which are expressed on the surface of B and T cells. Through this, the drug links cancer and immune cells, leading to cancer cell death. In the past, research has shown that blinatumomab is effective in treating ALL in adults. So, shares Medical XPress, researchers from the Princess Máxima Center wanted to test whether the treatment was also safe and effective in infants. 

30 infants with ALL were treated with blinatumomab, in conjunction with chemotherapy, over a 3-year period. Researchers compared their results with 214 infants previously treated solely with chemotherapy. They found that blinatumomab significantly improved life expectancy. 93% of infants treated with blinatumomab survived 2 years after diagnosis, compared to 66% treated with just chemotherapy. Additionally, 51% of infants treated with just chemotherapy either had their cancer return or become fatal within 2 years of treatment. In the blinatumomab group, this percentage was just 18%. Researchers also determined that infants treated with immunotherapy experienced less treatment-related side effects. 

Although more research may be done on larger population sizes, this does suggest that ALL with KMT2A arrangements could come with a better prognosis in the future. 

What is Acute Lymphoblastic Leukemia (ALL)? 

Also known as acute lymphocytic leukemia, acute lymphoblastic leukemia is a form of cancer that affects the blood and bone marrow. Acute means that the cancer progresses rapidly. Lymphoblastic refers to lymphocytes, a type of white blood cell. In ALL, the cancer forms from immature lymphocytes; the body then begins to produce immature blood cells, resulting in symptoms. ALL is often severe and treatment-resistant in adults. It is the most common form of childhood cancer and is treatable in most situations. Doctors aren’t sure what causes ALL, but they have identified certain factors that increase the risk: radiation exposure, prior cancer treatment, genetic conditions, or having a sibling with ALL. 

Symptoms of acute lymphoblastic leukemia may, but do not always, include:

• Abnormal bleeding, such as bleeding from the gums or frequent nosebleeds
• Extremely pale skin
• Bone pain
• Fever
• Dizziness or lightheadedness
• Easy bruising
• Recurrent infections
• Fatigue and general weakness
• Shortness of breath
• Swollen lymph nodes