IN8bio (INAB) Study Result summary

Study background and rationale

• Phase I trial evaluated safety and efficacy of allogeneic gamma-delta T cells (INB-100) to prevent relapse in high-risk leukemia patients post haploidentical stem cell transplant.

• Patients had intermediate or high-risk features, including poor genetics and mutations such as FLT3 and TP53, and received no maintenance therapy.

• The study targeted the period of immune vulnerability post-transplant, aiming for durable immune surveillance and relapse prevention.

• Historical controls from CIBMTR and KUCC were used for comparison, highlighting the unmet need in AML relapse prevention.

Study design and patient population

• Open-label, single-center, dose-escalation phase I trial with up to three dose levels of gamma-delta T cells.

• Included both original and expansion cohorts, with a median patient age of 68 and high-risk disease profiles.

• Many patients had failed multiple prior therapies, including CAR-T treatments.

• Two dose levels evaluated; dose level 2 (3x10^6 cells/kg) selected as recommended phase II dose.

• Expansion cohort ongoing, aiming for up to 25 patients and additional centers.

Efficacy results

• 100% of AML patients remain in complete remission, with a median follow-up of 20.1 months.

• One-year progression-free survival (PFS) and overall survival (OS) rates reached 100% for AML patients.

• Median complete remission duration in the original cohort is 23.3 months, with some patients in remission over three years.

• Compared to historical controls, INB-100 showed markedly lower relapse and mortality rates at one year.

• Across all patients, PFS was 81.3%, with durable remissions observed even in those with high-risk mutations.