The patients in this Phase II clinical trial are in complete hematological remission following intense chemotherapy regimens, but retain acute lymphoblastic leukemia (ALL) cancer cells in their bone marrow – so called minimal residual disease (MRD). Various reports have confirmed that ALL patients with MRD following chemotherapy have a significantly worse prognosis than patients without MRD.
Interim results for the ongoing Phase II clinical trial of blinatumomab for ALL find the BiTE antibody was able to eliminate MRD. Approximately six patients have been enrolled so far in the trial. Approximately four patients have concluded at least two cycles of therapy with blinatumomab, and three out of these four patients turned MRD-negative after the first treatment cycle. One patient achieved stable disease after the first treatment cycle and does not show signs of hematological relapse to date, the company said.
D Hoelzer, chairman of the German Multicenter Study Group for Adult Acute Lymphoblastic Leukemia, said: Today patients with MRD-positive ALL after first line therapy have very few options for treatment, and a very high likelihood of relapse. The ability to convert a patient’s MRD status from positive to negative could lead to better clinical outcomes.
These data suggest that blinatumomab may hold the potential to be an effective consolidation therapy after prior incomplete response to chemotherapy or even targeted therapy.