Real-world use of blinatumomab in adult patients with B-cell acute lymphoblastic leukemia in clinical practice: results from the NEUF study

This retrospective observational study (NEUF) included adult patients with B-cell acute lymphoblastic leukemia (B-cell ALL) who had received blinatumomab for the treatment of minimal residual disease-positive (MRD+) or relapsed/refractory (R/R) B-cell ALL via an expanded access program (EAP). Patients were eligible if blinatumomab was initiated via the EAP between January 2014 and June 2017. Patients were followed from blinatumomab initiation until death, entry into a clinical trial, the end of follow-up, or the end of the study period (December 31, 2017), whichever occurred first. Of the 249 adult patients included, 109 were MRD+ (83 Philadelphia chromosome-negative [Ph-] and 26 Philadelphia chromosome-positive [Ph+]) and 140 had a diagnosis of R/R B-cell ALL (106 Ph- and 34 Ph+). In the MRD+ group, within the first cycle of blinatumomab treatment, 93% (n = 49/53) of Ph- and 64% (n = 7/11) of Ph+ patients with evaluable MRD achieved an MRD response (MRD < 0.01%). Median overall survival (OS) was not reached over a median follow-up time of 18.5 months (Ph-, 18.8 [range: 5.1-34.8] months; Ph+, 16.5 [range: 1.8-31.6] months). In the R/R group, within two cycles of blinatumomab, 51% of Ph- and 41% of Ph+ patients achieved complete hematologic remission (CR/CRh/CRi), and 83% of Ph- and 67% of Ph+ MRD-evaluable patients in CR/CRh/CRi achieved an MRD response. Median (95% confidence interval) OS was 12.2 (7.3-24.2) months in the R/R Ph- subgroup and 16.3 (5.3-not estimated) months in the R/R Ph+ subgroup. This large, real-world data set of adults with B-cell ALL treated with blinatumomab confirms efficacy outcomes from published studies.