In a significant advancement for leukemia treatment, IN8bio's innovative gamma-delta T cell therapy INB-100 has demonstrated exceptional efficacy in Phase 1 trials for high-risk acute myeloid leukemia (AML) patients. The results, presented at the 2025 Transplantation & Cellular Therapy Meetings in Hawaii, showcase the therapy's potential to revolutionize post-transplant care.
Unprecedented Clinical Outcomes
The trial data revealed remarkable durability of remissions, with zero relapses observed in AML patients over a median follow-up period of 20.1 months. The therapy achieved a 90.9% progression-free survival (PFS) rate and 100% overall survival (OS) at one year, significantly outperforming historical benchmarks for this high-risk patient population.
"AML patients undergoing allogeneic HSCT face high relapse rates with limited post-transplant therapeutic options," explained William Ho, Chief Executive Officer and co-founder of IN8bio. "The durability of response and safety profile observed to date with INB-100 support its potential to set a new standard in post-transplant leukemia management."
Safety Profile and Mechanism of Action
The treatment demonstrated an impressive safety profile with no instances of cytokine release syndrome (CRS), neurotoxicity (ICANS), or dose-limiting toxicities. Importantly, researchers observed evidence of in vivo expansion and long-term persistence of gamma-delta T cells, suggesting sustained immune surveillance against residual leukemic cells.
Addressing a Critical Medical Need
AML represents a significant health burden, with approximately 20,000 new cases and 11,500 deaths annually in the United States. Current post-hematopoietic stem cell transplant (HSCT) outcomes are concerning, with relapse rates reaching up to 50% of patients.
Dr. Michael Bishop, Director of the Hematopoietic Cellular Therapy Program at the University of Chicago and IN8bio Scientific Advisory Board member, emphasized the significance of these results: "Despite decades of progress in transplantation, relapse remains the primary driver of mortality in AML patients post-HSCT. The INB-100 data showing durable remission without maintenance therapy is highly encouraging."
Path Forward
IN8bio is accelerating patient enrollment in the INB-100 program, with plans to complete the expansion cohort enrollment in 2025. The FDA has confirmed that relapse-free survival (RFS) will be an acceptable primary endpoint for a future pivotal randomized controlled trial, clearing the path for potential regulatory advancement.
The company's innovative approach leverages the innate tumor-targeting properties of gamma-delta T cells, potentially addressing a critical gap in the current treatment landscape for AML patients undergoing stem cell transplantation.
