Blinatumomab Consolidation Post Autologous Stem Cell Transplantation in Patients with Diffuse Large B-Cell Lymphoma.

Outcomes in patients with relapsed diffuse large B-cell lymphoma (DLBCL) who undergo autologous stem cell transplant (auto-SCT) are poor. Blinatumomab is a CD3/CD19 bispecific T-cell engager that directs cytotoxic T-cells to CD19+ cells. Here, we performed a pilot study of blinatumomab consolidation following auto-SCT in 14 patients with DLBCL or transformed follicular lymphoma. All patients underwent standard of care auto-SCT with BEAM conditioning followed by one cycle (4 weeks continuous infusion) of blinatumomab consolidation starting at day 42 post auto-SCT. All 14 patients treated on study completed BEAM auto-SCT and one cycle of post-transplant blinatumomab. Five patients developed grade 1 cytokine release syndrome (CRS), with no grade 2 or higher CRS. Immune effector cell-associated neurotoxicity syndrome (ICANS) was not observed. Patients were followed for 3 years post auto-SCT with median follow up of 37 (range 12-65) months. One hundred days post auto-SCT (one month post blinatumomab consolidation) 12 (86%) patients had achieved complete remission (CR). At 1 year post auto-SCT 7 patients (50%) remained in CR and 1 patient had died of progressive disease (PD). Patients who relapsed had a lower CD8/CD4 T-cell ratio before starting blinatumomab compared with patients who remained in remission. This pilot study demonstrates blinatumomab consolidation post auto-SCT is safe and well tolerated. Strategies to increase CD8/CD4 ratio and utilize additional cycles of consolidation in a larger randomized trial are needed to confirm the efficacy of consolidation with blinatumomab post auto-SCT. This trial was registered at www.clinicaltrials.gov as #NCT03072771.