NeoImmuneTech, Inc. reported that Nature Communications published the results of an in vivo study combining the long-acting human IL-7, NT-I7, with chimeric antigen receptor (CAR) T cells directed against CD19+ B cell lymphoma and acute myeloid leukemia. The study led by Dr. DiPersio and his team at Washington University investigated the impact of NT-I7 on in vivo CAR-T cell expansion and anti-tumor response employing sophisticated models of B cell lymphoma or acute myeloid leukemia and an immune competent syngeneic model of acute promyelocytic leukemia. Utilizing these tools, the group tested whether NT-I7 could expand a less differentiated CAR-T product with improved durability and tumor killing abilities in multiple models of hematological cancer.

Over the past 10 years, CAR-T cell therapy has become routinely used to treat patients with refractory hematologic malignancies. Despite progress, long-lived memory responses and long-term in vivo persistence of CAR-T cells have yet to be consistently achieved to prevent tumor cell escape and clinical relapse. In the study reported in Nature Communications, NT-I7 protected CD19-targeting CAR-T cells from cell death, enhancing their viability while promoting their expansion in the presence of CD19+ tumor cells. CAR-T cells expanded in the presence of NT-I7 were less differentiated but with equivalent effector cytokine secreting abilities.

Treatment of tumor bearing mice with NT-I7 enhanced in vivo expansion and subsequent anti-tumor effects of CAR-T cells targeting CD19+ B cell lymphoma or CD33+ acute-myeloid leukemia. The combination of NT-I7 and CAR-T cells dramatically extended survival. Impressively, co-treatment of tumor bearing mice with NT-I7 reduced the minimum number of CAR-T cells needed to achieve a survival benefit by imparting increased tumor killing abilities to CAR-T cells on a per cell basis and expanding CAR-T cells in vivo.

These studies provide compelling evidence that NT-I7 has the potential to enhance CAR-T therapy for the treatment of hematological diseases by promoting CAR-T anti-tumor activity, expansion and persistence. This study presented in Nature Communications demonstrates the potential for NT-I7 to support impactful clinical use of multiple CAR-T therapies with improved safety and tolerability. Strategic combination of NT-I7 with CD19-targeting CAR-T cells is currently being tested as part of a multi-site clinical trial (NCT05075603) for the treatment of relapsed/refractory large B-cell lymphoma.