NEW YORK, July 9, 2026
IN8bio announced the publication of peer-reviewed Phase 1 clinical trial results for its investigational DeltEx™ Drug Resistant Immunotherapy (DRI) in The Journal of Clinical Oncology (JCO), highlighting encouraging outcomes in patients with newly diagnosed glioblastoma (GBM). The published study evaluated INB-200, an autologous genetically modified gamma-delta (γδ) T cell therapy engineered to resist chemotherapy through MGMT gene modification, allowing the immune cells to remain active during standard temozolomide (TMZ) treatment. Administered directly into the brain following surgery and chemoradiation, the therapy demonstrated a median progression-free survival (mPFS) of 16.1 months in repeat-dose patients, more than double the approximately 6.9-month benchmark achieved with standard-of-care treatment alone, while maintaining a favorable safety profile without dose-limiting toxicities, cytokine release syndrome, or immune-related neurotoxicity.
DeltEx DRI Demonstrates Strong Clinical Activity with Favorable Safety Profile
The Phase 1 frequency-escalation study enrolled 13 patients with newly diagnosed glioblastoma who received one, three, or up to six intracranial doses of DeltEx DRI alongside the established Stupp treatment regimen, consisting of surgical resection, chemoradiation, and maintenance temozolomide chemotherapy. Across all treated participants, the therapy achieved a median progression-free survival of 9.9 months, representing a 43.5% improvement over historical outcomes reported with standard therapy alone. The greatest clinical benefit was observed among patients receiving repeated doses, where median overall survival reached 19.5 months, exceeding the historical standard-of-care median overall survival of approximately 14.6 months. Importantly, investigators reported no dose-limiting toxicities (DLTs), no cytokine release syndrome (CRS), and no immune effector cell-associated neurotoxicity syndrome (ICANS), supporting the feasibility of repeated intracranial administration of chemotherapy-resistant γδ T cells during ongoing chemotherapy.
Chemotherapy-Resistant Gamma-Delta T Cells Offer Novel Treatment Strategy
DeltEx™ Drug Resistant Immunotherapy is designed to overcome one of the major limitations in treating glioblastoma, where residual tumor cells often survive despite aggressive surgery, radiation, and chemotherapy. IN8bio engineers gamma-delta T cells with an MGMT-expressing lentivector, enabling them to resist the damaging effects of alkylating chemotherapy while remaining capable of attacking cancer cells. By delivering these modified immune cells directly into the tumor cavity, the therapy is intended to eliminate residual malignant cells, enhance anti-tumor immune responses, and improve long-term disease control. Researchers believe this strategy creates important synergy between conventional chemotherapy and cellular immunotherapy, potentially establishing a new treatment paradigm for one of the most aggressive and difficult-to-treat forms of brain cancer, where survival has remained largely unchanged for more than two decades.
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Publication Strengthens Clinical Development of IN8bio’s DeltEx Platform
The publication in The Journal of Clinical Oncology, one of the world’s leading oncology journals, represents a significant scientific milestone for IN8bio and validates the clinical foundation of its DeltEx™ platform. The company believes the peer-reviewed data support continued advancement of INB-200 and INB-400, both chemotherapy-resistant gamma-delta T cell therapies designed for glioblastoma. Beyond brain cancer, IN8bio continues to develop a broader pipeline of γδ T cell therapies and γδ T cell engagers targeting multiple oncology and autoimmune indications, including INB-600 for solid tumors and INB-100 for high-risk leukemia patients undergoing stem cell transplantation. The company expects to provide additional clinical updates on its DeltEx DRI glioblastoma program later this year as it continues working toward improving outcomes for patients facing one of oncology’s greatest unmet medical needs.
Source: IN8bio press release
