IN8bio Updates on Phase 1 INB-200 Study at 2024 ASCO Annual Meeting

IN8bio, Inc., a clinical-stage biopharmaceutical company, revealed promising preliminary outcomes from a study of its gamma-delta (γδ) T cell therapy, INB-200, at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago. This innovative therapy is aimed at treating glioblastoma (GBM), a highly aggressive brain cancer. The preliminary data, collected until May 30, 2024, show that 92% of the evaluable patients treated with INB-200 surpassed the median progression-free survival (PFS) of seven months typically achieved with the standard-of-care Stupp regimen.

The Phase 1 study investigated the safety and initial efficacy of adding DeltEx DRI γδ T cells to the maintenance therapy with temozolomide (TMZ). Thirteen patients were enrolled and treated across three dosing cohorts—one dose in Cohort 1, three doses in Cohort 2, and six doses in Cohort 3. Positive preliminary results were noted across all cohorts. Notably, all patients who completed their prescribed treatments exceeded the median PFS of seven months, with one patient in Cohort 2 remaining progression-free for nearly three years.

Dr. Burt Nabors, Division Director of Neuro-oncology at the Heersink School of Medicine, University of Alabama at Birmingham, emphasized the study's significance, noting that the inclusion of multiple intracranial injections of γδ T cells could offer a substantial advancement in treatment outcomes for GBM patients.

The standard treatment for newly diagnosed glioma patients involves primary resection, followed by six weeks of daily chemoradiation therapy and six cycles of monthly TMZ therapy, achieving a median PFS of 7 months. However, patients in the Phase 1 study of INB-200 have shown promising improvements. The safety profile of INB-200 is also encouraging, with no reported cell therapy-related toxicities, such as immune effector cell-associated neurotoxicity syndrome or cytokine release syndrome, even at the highest dose of six infusions.

Dr. Trishna Goswami, Chief Medical Officer of IN8bio, highlighted the absence of significant adverse events related to the cell therapy across all doses. The company is now progressing to Phase 2 trials with INB-400, which involves a regimen of up to six infusions of autologous γδ T cells in combination with the Stupp protocol for newly diagnosed patients.

The ASCO presentation detailed various key findings from the Phase 1 study, including the superiority of INB-200 treated patients over the standard PFS of seven months. Furthermore, one patient with an IDH-mutant glioma remains alive and progression-free at nearly 35 months. These results suggest potential durability and efficacy of the DeltEx DRI γδ T cells.

The radiological assessments showed indications of treatment effects, such as changes in MRI enhancements and resolution of midline shifts. One patient exhibited a 36% reduction in a lesion, pointing toward a positive treatment effect.

William Ho, CEO and co-founder of IN8bio, expressed optimism about the continuing maturation of Phase 1 study results and anticipated further disclosures from long-term follow-up at future medical meetings.

INB-200 represents a novel approach, involving genetically modified autologous DeltEx DRI γδ T cells for solid tumors. This platform aims to enable γδ T cells to survive and function alongside chemotherapy, leveraging their natural ability to target and destroy cancer cells. IN8bio’s DeltEx platform attempts to develop cell therapies that can distinguish between healthy and diseased tissue, offering a specialized treatment for solid and liquid tumors.

The company has already initiated a Phase 2 trial of INB-400 in GBM and continues to evaluate the safety and efficacy of its innovative γδ T cell therapies across multiple ongoing trials.