Repeat-doses of DeltEx™ Drug-Resistant Immunotherapy gamma-delta (γδ) T cells (DRI) nearly doubled median progression-free survival (mPFS) to 13.0 months compared to only 6.6 months (+97%) in a control cohort treated with the standard-of-care (SOC) Stupp protocol
Median overall survival (mOS) continues to climb, currently at 17.2+ months as of December 31, 2025, with several patients who remain progression-free for multiple years (1.4 – 4.6 years) compared to only 13.2 months for SOC (+30.3%)
Treatment remains well tolerated with no treatment related severe adverse events (SAEs) or dose limiting toxicities (DLTs) observed

NEW YORK, Jan. 12, 2026 (GLOBE NEWSWIRE) -- IN8bio, Inc. (NASDAQ:INAB), a clinical-stage biopharmaceutical company developing innovative gamma-delta (γδ ) T cell therapies for cancer and autoimmune diseases, reported updated clinical data from its INB-200 Phase 1 and INB-400 Phase 2 trials in newly diagnosed glioblastoma (GBM). The prior results were presented at the 2025 Society for Neuro-Oncology (SNO) Annual Meeting. The data continue to demonstrate meaningful and durable improvements in progression-free survival when compared with both historical standard-of-care (SOC) Stupp protocol data and concurrently enrolled SOC treated patients.

Patients in both the Phase 1 and 2 who received repeated doses of the Company's investigational therapy, DeltEx™ Drug-Resistant Immunotherapy gamma-delta (γδ) T cells (DeltEx DRI) (N=14), experienced substantial improvements in both median progression-free (mPFS) and median overall survival (mOS) across multiple clinical centers. This data is put into greater context compared to contemporaneously enrolled patients treated only with SOC at the same clinical trial sites (N=10), forming a concurrently treated control cohort:

Median progression-free survival (mPFS): DeltEx DRI 13.0 months vs. 6.6 months with SOC (a +97% improvement).
Median overall survival (mOS): DeltEx DRI, not yet reached, currently 17.2+ months and rising, compared with 13.2 months (final mOS) for SOC.
Durability: DeltEx DRI, eight of fourteen patients (57%) remained progression-free longer than their expected overall survival (OS) based on age and MGMT status (a biomarker used to stratify GBM patients and impacting response to chemotherapy), compared with just a single patient (10%) in the control group.
Long-term benefit: Several DeltEx DRI treated patients remain progression-free beyond two years without experiencing any significant DRI related SAEs or DLTs.

William Ho, CEO and Co-founder of IN8bio, commented, "GBM is an extremely aggressive and devastating brain cancer, with a short median survival of only ~12 months and no meaningful innovation in over twenty years. The contrast between our repeat-dose DeltEx DRI patients and the SOC controls treated at the same centers demonstrates a profound improvement. The increase in mPFS, particularly in the newly diagnosed GBM setting, is meaningful time for these patients. The durability of these mPFS results, combined with a well-tolerated safety profile, underscore the potential of our γδ T cell therapy to meaningfully improve newly diagnosed GBM treatment and patient outcomes."

For the first time, IN8bio presented data from a control group of patients that were contemporaneously enrolled and treated only with the SOC protocols at the same clinical centers with the same treating physicians as the DeltEx DRI cohorts. The SOC control patients performed in-line with expectations based on historical GBM mPFS of 6.9 months, despite a greater number of patients receiving gross total resections. This demonstrates both the aggressive nature of GBM, even with SOC treatment, and the significant need for new treatment options. The funds received from IN8bio's recent financing announced late in 2025 will support further discussions with the FDA on potential clinical pathways, including any potential for accelerated approval.

Across both Phase 1, INB-200, and Phase 2, INB-400, trials at multiple centers, DeltEx DRI γδ T cells continued to demonstrate a well-tolerated safety profile, with:

No DLTs
No cytokine release syndrome (CRS)
No immune effector cell-associated neurotoxicity (ICANS)
No unexpected infections or SAEs

Kate Rochlin, PhD, Chief Operating Officer, IN8bio, added, "These results show a consistent biological and clinical story. In the DeltEx DRI treated patients, we observed persistent and elevated levels of γδ T cells in circulation, immune cell infiltration within the tumors, and broader systemic immune activation. This is significant in understanding the immune impact in patients treated with this therapy, particularly in a setting traditionally considered a "cold" tumor combined with long-term lymphodepleting chemotherapy. Furthermore, these findings indicate that localized intracranial delivery of DeltEx DRI can drive systemic immune responses, an aspect that could be important in fighting GBM. This is a disease marked by profound treatment-induced lymphodepletion, rapid progression, and poor outcomes.

The data presented at SNO was the first time IN8bio had presented multi-center DeltEx treated and control SOC patient data from the both 1 and Phase 2 trials. Across all sites, early trends in mPFS and mOS were consistent with the original INB-200 trial, reinforcing:

Reproducibility across clinical centers
Scalability of the repeated-dose approach
A strong foundation for further development

About IN8bio

IN8bio is a clinical-stage biopharmaceutical company developing γδ T cell product candidates for unmet medical needs. γδ T cells are a specialized population of T cells that possess unique properties, including the ability to differentiate between healthy and diseased tissue. The Company's lead program, INB-100, is focused on acute myeloid leukemia, evaluating haplo-matched allogeneic γδ T cells given to patients following a hematopoietic stem cell transplant. The Company is also evaluating autologous DeltEx DRI γδ T cells, in combination with standard of care, for glioblastoma in its INB-200 and 400 programs, and INB-600, advancing novel γδ T cell engagers for potential oncology and autoimmune indications. For more information about IN8bio, visit www.IN8bio.com.

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IN8bio, Inc.

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IN8bio Presents Updated Phase I/II Data Demonstrating Meaningful and Durable Survival Improvements in Newly Diagnosed Glioblastoma