Complete Remissions Post Infusion Of Multiple Tumor Antigen Specific T Cells For The Treatment Of High Risk Leukemia And Lymphoma Patients After Hct

Background/Objectives: Relapse of hematologic malignancies after hematopoietic cell transplantation (HCT) confers high mortality because of progressive disease and graft-vs.-host disease (GVHD). Hence, we hypothesized that tumor-associated antigen-specific lymphocytes (TAA-L) would be specific, diminish immune escape, and could safely decrease cancer burden. Design/Methods: We expanded lymphocytes reactive to TAA: WT1, PRAME, Survivin, which are over-expressed and immunogenic in hematologic malignancies. On a prospective study: NCT002203902, eligible patients received TAA-L infusions at 4 sequential dose levels: 0.5 to 4.0e7/m2 per dose. Results: Thirty-two donor-derived TAA-L products were generated and lacked alloreactivity in vitro. TAA-L products comprised predominantly effector memory T-cells, with Conclusion: This unique immunotherapeutic has been well tolerated without causing life-threatening cytokine release syndrome. Despite aggressive and multiply relapsed disease, 8/10 evaluable patients have demonstrated evidence of disease control after TAA-L, with 50% complete response, suggesting that TAA-L may have efficacy in relapsed high-risk hematological malignancies after HCT. Disclosures Bollard: Torque: Membership on an entity9s Board of Directors or advisory committees; Cellectis: Membership on an entity9s Board of Directors or advisory committees; Neximmune: Consultancy, Membership on an entity9s Board of Directors or advisory committees.