Historically, outcomes of adult patients (pts) with ALL who fail to enter remission with standard induction chemotherapy are very poor. Blinatumomab, a bispecific CD3/CD19 antibody, has shown remarkable activity in relapsed/refractory (r/r) ALL. While allogeneic HCT is the recommended consolidation therapy for r/r ALL pts who respond to salvage therapy, HCT and toxicity outcomes for those who received blinatumomab salvage and HCT remains largely unknown. A retrospective review of r/r ALL pts medical records, who received blinatumomab salvage therapy from 2012 to 2018 at our institution was obtained. Only pts who responded to blinatumomab and underwent HCT were included (n=29). Kaplan-Meier curves and the log-rank test were used to evaluate the overall survival (OS) and progression-free survival (PFS). Cumulative incidence (CI) curves and the Gray test were used to examine the differences in relapse rates and non-relapse mortality (NRM). The median age at the time of HCT was 29 years (range: 19-65), and 8 pts (28%) were over 50 years old. HCT was done in complete remission- (CR)-1 (n=14, 48%) or ≥CR-2, with 2pts receiving blinatumomab salvage after relapse from a prior HCT. Pts received transplant from a matched sibling (n=11), matched unrelated (n= 12), haploidentical donor (n=5) or double umbilical cord blood (n=1) after myeloablative (n=20, including TBI+VP16, n=15) or reduced intensity (n=9) conditioning. The graft source was PBSCs in 25 pts (86.2%). Graft-versus-host disease (GVHD) prophylaxis was tacrolimus/sirolimus-based (n=19, 66%), and post-HCT cyclophosphamide (n=5, 17%) for haploidentical transplants. At the time of salvage therapy initiation, pts had either gross residual (n=22) or minimal residual disease (MRD+) (n=7). Negative MRD remission status was achieved prior to HCT in 15 pts, including those who were MRD+ before blinatumomab salvage. With a median follow up of 21.7 months (mo) (range: 1.1-55.7) for all pts and 6.4 mo for surviving pts, the 1-year OS and PFS were 72.8% (95% CI: 48.5-87.0) and 63.0% (95% CI: 38.8-79.8), respectively (Fig 1). Causes of death post-HCT were GVHD (n=3); NRM (n=4; 3 sepsis and 1 regimen related toxicity) and relapse (n=3). The CI of relapse at 1 and 2 years were 24.9% (95% CI: 8.6-45.3) and 45.9%, (95% CI: 20.3-68.3), respectively. NRM at 100 days was 6.9% (95% CI: 1.2-20.0) and at 12 mo was 12.1% (95% CI: 2.7-29.0). The incidence of grades 3-4 acute GVHD and extensive chronic GVHD at 24 mo were 25.0% (95% CI: 8.7-45.5) and 38.8% (95% CI: 14.2-63.1), respectively. No cases of veno-occlusive disease post-HCT were reported. We present here, for the 1st time, detailed data showing the tolerability and efficacy of HCT following salvage therapy with blinatumomab. No unexpected toxicities were noted post-HCT and the study showed encouraging 1-year OS and PFS with. Longer-term follow-up is ongoing for these patients.