A major obstacle to the development of effective CAR T-cells for T-cell malignancies is that the surface marker profile of malignant T-cells largely overlaps that of activated T lymphocytes. We developed a CAR T-cell approach that targets CD7, a T-cell marker highly expressed in all cases of T-cell ALL, including ETP-ALL. Its expression is also highly stable even in T-ALL cells exposed to chemotherapy. To prevent fratricide effect of the T cells, surface CD7 expression are effectively downregulated with the expression of an anti-CD7 Protein Expression Blocker (PEBL). Patients will receive anti-CD7 PEBL CART-cells. This will allow targeting the entire leukemia cell population to induce deeper and more durable remissions.
The objective of this study is to assess the safety and efficacy of anti-CD7 CAR T-cells in patients with refractory or relapsed T-lineage acute lymphoblastic leukemia (T-ALL).