IN8bio, Inc. announced new positive data from the Phase 1 investigator-sponsored trial of INB-100 in leukemia patients. The data presented at the 49th Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT) showed that 100% of evaluable patients (n=7) treated with INB-100 remained alive, progression-free, and in durable complete remission (CR) as of April 21, 2023, indicating the curative potential of INB-100 for high-risk or relapsed AML and other hematologic malignancies undergoing hematopoietic stem cell transplantation (HSCT). The latest data on immune reconstitution presented at EBMT showed significant allogeneic gamma-delta T cell expansion and persistence in patients through the first 180 days post-treatment.

Patients who received INB-100 treatment at Dose Level 2 exhibited an average of 82.9x greater gamma-delta T cell expansion at 60 days compared to patients undergoing haploidentical HSCT without INB-100 therapy. The gamma-delta T cell levels in Dose Level 2 patients are also, on average, 12.8x greater than those achieved in Dose Level 1, demonstrating a dose-response related to the gamma-delta T cell infusion. Elevations in CD4+, CD8+ T cells, NK cells and B cells have also been observed, indicating a broad positive immune response.

The study's updated safety data reported low-grade (1-2) graft versus host disease (GvHD) in all patients treated, which was steroid-responsive, and had a more rapid onset at higher dose levels. No dose limiting toxicities (DLTs) have been observed. As of April 21, 2023, all evaluable patients across Dose Levels 1 and 2 remained on study and in CR, with one patient remaining progression free for over 3 years.

Additional treated patients have remained progression free for 33.9, 22.2, 7.8, 5.8, 5.6 and 2.6 months, respectively. The positive outcome of ongoing durable patient CRs, combined with the benefit/risk profile, led to the decision to select Dose Level 2 as the RP2D. The trial is being expanded at this dose level, and additional patients are actively being enrolled and treated in the study, with updated data expected to be presented at a medical meeting later this year.