A retrospective analysis of 38 children with relapsed or refractory acute lymphoblastic leukemia (ALL) who were treated with the bispecific T-cell engager blinatumomab at a single center in Germany over a 10-year period found that, among nine long-term survivors who achieved continuous molecular remission, all underwent haploidentical HSCT both before and after treatment with blinatumomab. The study by researchers at University Children’s Hospital Tubingen was published in the European Journal of Haematology in December 2020.
Patients’ median age was 4.6 years at diagnosis and 9.8 years at initiation of blinatumomab therapy. Two-thirds of the patients had had a second or subsequent relapse; 71% had undergone at least one HSCT. Seventy-one percent also had blast infiltration in the bone marrow above 25% at the time they began blinatumomab treatment. All patients received at least one cycle of blinatumomab. Treatment spanned the period 2008 to 2017.
Thirteen patients (34%) responded to blinatumomab; eight achieved complete MRD negativity. Eighteen patients (47.4%) developed cytokine release syndrome. Eight neurotoxicity events were recorded over 78 treatment cycles (15%). With a median follow-up time for survivors of 54 months, median overall survival for the nine long-term survivors was 51 months and for all patients 11.1 months.
“All nine of our patients currently alive and in remission received HSCT before and after blinatumomab administration,” the researchers stated. “In patients with relapsed ALL responding to therapy with blinatumomab, a subsequent hematopoietic stem cell transplantation (HSCT) is crucial for better relapse-free survival.”
- Queudeville M, Schlegel P, Heinz AT, et al. Blinatumomab in pediatric patients with relapsed/refractory B-cell precursor acute lymphoblastic leukemia [published online ahead of print, 2020 Dec 15]. Eur J Haematol. 2020;10.1111/ejh.13569. doi:10.1111/ejh.13569