Background: Advances in the treatment of pediatric acute lymphoblastic leukemia (ALL) have significantly improved outcomes, with overall survival rates exceeding 90%. Despite these favorable results, relapse and resistance to therapy remain major clinical challenges, and ALL is still the second leading cause of cancer-related mortality in children, after central nervous system tumors. The development of immunotherapy has led to new treatment options, including blinatumomab. The aim of this study was to assess the efficacy of blinatumomab treatment and to evaluate its safety profile in pediatric patients with high-risk precursor B-cell ALL. Material and Methods: We conducted a retrospective single-center cohort study including 13 pediatric patients with high-risk BCP-ALL treated with blinatumomab between 2017 and 2025 in Lublin, Poland. Primary outcomes were MRD negativity and overall survival. Safety was assessed using CTCAE criteria. Results: MRD positivity before treatment was present in 8/13 patients. After the first cycle, 62.5% achieved MRD negativity, increasing to 75.0% overall after two cycles. Kaplan-Meier estimated 12-month OS was 83.3%, and 24-month OS was 64.8%. Adverse events occurred in 69.2% of patients; grade 3 toxicity in 23.1%. No life-threatening toxicity occurred. Conclusions: In this small retrospective cohort, blinatumomab demonstrated encouraging MRD response, favorable survival estimates, and acceptable tolerability in pediatric high-risk BCP-ALL. Larger prospective multicenter studies are warranted. Keywords: blinatumomab, immunotherapy, pediatric, acute lymphoblastic leukemia, bispecific antibody
Mitura‑Lesiuk et al. (2026) studied this question.