Blinatumomab (CD19×CD3 BiTE) consolidation cuts relapse in high-risk Ph− adult B‑ALL (5‑yr CIR 23% vs 49%)

Blinatumomab is a CD19×CD3 bispecific T‑cell engager given here as an immunotherapy “overlay” on intensive chemotherapy, tested in the Phase 2 GRAALL‑2014/B‑QUEST substudy in newly diagnosed high-risk (KMT2A‑r, IKZF1 deletion, and/or end‑of‑induction MRD ≥10^-4) Ph− B‑ALL adults age 18–59; 94 patients received up to five 28‑day cycles during consolidation/maintenance vs a post hoc control cohort treated on the same backbone pre‑QUEST (n=90). At 5 years, blinatumomab was associated with lower relapse (CIR 23% vs 49%; p=.001) and better DFS (68% vs 42%; p=.001) and OS (79% vs 60%; p=.03)—notably higher than published high‑risk Ph− adult ALL benchmarks where 5‑yr OS often sits around ~50–60% with chemo/alloHSCT strategies. Transplant‑eligible patients appeared to benefit overall, but among those who ultimately underwent alloHSCT there was no clear additional DFS advantage, raising the question of whether blinatumomab-enabled MRD control can spare some patients from transplant without compromising cure (trial ID: NCT03709719).