Improved Survival in Young B-ALL Patients with Blinatumomab | Mark Litzow, MD | #EHA 2025

My name is Dr. Mark Litzow. I am a hematologist at the Mayo Clinic in Rochester, Minnesota. And I want to tell you today a little bit about a clinical trial that I led using Blenotumumab. And Blenotumumab is a bispecific T-cell engaging molecule. It takes the variable region of an antibody that reacts with a protein on B-cell acutal lymphoblastic leukemia cells called CD19 and it's linked to an antibody that reacts with a protein on some immune cells called T-cells or thymocytes. And it brings the T-cell in close proximity to the leukemic cell and kills it. And this was actually developed about 10 years ago and was found to be beneficial in patients where their leukemia unfortunately had come back after chemotherapy. And it was found to be effective in that setting. And then we also studied it in patients where they had low levels of leukemia, what we call measurable residual disease, and was found to be beneficial there. So this clinical trial that I did, we added it to chemotherapy in patients who we thought had a good prognosis. They were in remission and their measurable residual disease testing was negative, so they were MRD negative. And what we did was we enrolled 488 patients and they went through several months of chemotherapy to get into remission. And then at that point, if they were measurable residual disease or MRD negative, we randomized them to either continue with what we call consolidation chemotherapy to consolidate their remission, or we added Blenetumumab to the consolidation chemotherapy. Blenetumumab has to be given by an intravenous infusion daily for four weeks. And so that's one cycle. So it's a month of treatment, then you get a two-week break and get another month. And we gave four cycles of this Blenetumumab. And what we found was that the patients that got Blenetumumab plus chemotherapy had a much better survival than the patients that got the chemotherapy alone. At three years, survival was 85% for the patients that got Blenetumumab plus chemotherapy and 68% for the patients that got chemotherapy. And as a result of this, the FDA approved Blenetumumab now for MRD negative patients. They kept the indication broad and said for consolidation chemotherapy to add it to consolidation chemotherapy. And I'm here at the European Hematology Association meeting in Milan, Italy. And we're presenting some data from a subset of patients from that study. And these were the younger patients on the study because we enrolled patients between the ages of 30 and 70 on this clinical trial, this E1910 trial. And so we're looking at this meeting at the patients that were between the ages of 30 and 55. And we found that particularly in these younger patients, Blenetumumab was very effective. So at three years, their survival was 92% versus 67% for patients that got chemotherapy. And we also looked at the patients between the ages of 30 and 40. And they had 100% survival with Blenetumumab versus about 70% for the patients that got chemotherapy. So we're very encouraged by these results. And we think that this is going to allow us to use more immune therapy, medications like Blenetumumab and some other ones, and allow us to reduce the amount of chemotherapy we give in the hopes that we can lessen some of the side effects that patients experience and yet continue to improve their remission rate and survival.