The effect of blinatumomab prior to allo-HSCT in adult patients with B-ALL

Adult patients with acute lymphoblastic leukemia (ALL) have a poor prognosis, and 5-year overall survival (OS) in adults aged >50 years is 20%. Blinatumomab has shown efficacy in patients with relapsed/refractory B-cell ALL (B-ALL) and has achieved minimal residual negativity; however, there are limited data on the impact of pretransplant blinatumomab in adults.

Here, we summarize a retrospective study on the effect of blinatumomab prior to allogeneic stem cell transplantation (allo-HSCT) in adult patients with B-ALL, published by Sayyed et al.¹ in Transplantation and Cellular Therapy.

Study design¹

• This retrospective study included adult patients with B-ALL who underwent allo-HSCT at the Princess Margaret Hospital, Toronto, CA, between January 2010 and December 2021.
• The study endpoints included OS, cumulative incidence of relapse, non-relapse mortality (NRM), and graft-versus-host disease and relapse-free survival (GRFS).

Key findings¹

Patient baseline characteristics

• A total of 117 patients were included in the analysis, of which 31 patients received blinatumomab before allo-HSCT
• Key baseline characteristics differed between the two cohorts, as summarized in Table 1

Table 1. Patient baseline characteristics*

Survival and relapse outcomes

• After a median follow-up of 36 months,
  • 2-year OS, GRFS, and the cumulative incidence of relapse was significantly higher in patients who received blinatumomab vs those who did not (Figure 1); and
  • the 2-year NRM and Grade 2–4/Grade 3−4 acute graft-versus-host disease at Day 100 was significantly lower in patients who received blinatumomab prior to allo-HSCT versus those who did not (Figure 1).
• The incidence of Grade 2−4 and Grade 3−4 acute graft-versus-host disease in the total cohort was 48.9% and 27.8%, respectively.
• Multivariate analysis revealed a significant association between pretransplant blinatumomab and improved OS and NRM.

Figure 1. 2-year outcomes in blinatumomab treated vs no blinatumomab groups* 

aGvHD, acute graft-versus-host disease; CIR, cumulative incidence of relapse; GRFS, GvHD-free and relapse-free survival; NRM, non-relapse mortality; OS, overall survival
*Data from Sayyed, et al.¹