Purpose: Although chimeric antigen receptor T-cell (CAR-T) therapy development for B-cell malignancies has made significant progress in the last decade, broadening the success to treating T-cell acute lymphoblastic leukemia (T-ALL) has been limited. We conducted two clinical trials to verify the safety and efficacy of GC027, an "off-the-shelf" allogeneic CAR-T product targeting T-cell antigen, CD7. Here, we report 2 patients as case reports with relapsed/refractory T-ALL who were treated with GC027.
Patients and methods: Both the trials reported here were open-label and single-arm. A single infusion of GC027 was given to each patient after preconditioning therapy.
Result: Robust expansion of CAR-T cells along with rapid eradication of CD7+ T lymphoblasts were observed in the peripheral blood, bone marrow, and cerebrospinal fluid. Both patients achieved complete remission with no detectable minimal residual disease. At data cutoff, 30 September 2020, 1 of the 2 patients remains in ongoing remission for over 1 year after CAR T-cell infusion. Grade 3 cytokine release syndrome (CRS) occurred in both patients and was managed by a novel approach with a ruxolitinib-based CRS management. Ruxolitinib showed promising activity in a preclinical study conducted at our center. No graft-versus-host disease was observed.
Conclusions: The two case reports demonstrate that a standalone therapy with this novel CD7-targeted "off-the-shelf" allogeneic CAR-T therapy may provide deep and durable responses in select patients with relapsed/refractory T-ALL. GC027 might have a potential to be a promising new approach for treating refractory/relapsed T-ALL. Further studies are warranted.
©2020 American Association for Cancer Research.