Interim results from the Phase 1b MAST trial show that azercabtagene zapreleucel (azer-cel), an off-the-shelf CAR T-cell therapy, is highly active in several B-cell cancers. In heavily pretreated patients who had not received prior CAR T therapy, all 4 chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) patients achieved partial responses, 3 of 5 marginal zone lymphoma (MZL) patients had complete responses, and prior data in diffuse large B-cell lymphoma (DLBCL) showed a 75% overall response rate with 55% complete responses.
Azer-cel differs from standard CAR T therapies because it uses donor T-cells, allowing immediate availability. This “off-the-shelf” approach helps patients with rapidly progressing disease and overcomes the delays and logistical challenges of autologous CAR T manufacturing. The FDA granted Fast Track designation for DLBCL in March 2025.
The trial is expanding to include other B-cell cancers, such as primary CNS lymphoma, Waldenström macroglobulinemia, and mantle cell lymphoma. Researchers are also testing azer-cel in combination with BTK inhibitors for patients who have failed prior therapy. The company is preparing for pivotal studies with FDA-aligned dosing and trial design.