Study of Isatuximab and Cemiplimab in Relapsed or Refractory Natural Killer/T-cell Lymphoid Malignancy

This study is to analyze the efficacy of PD1 inhibitor and anti-CD38 antibody in relapsed or refractory NK/T-cell lymphoid malignancy. The investigational products of this study are cemiplimab (PD1 inhibitor) and isatuximab (anti-CD38 antibody). The rationale for the use of cemiplimab in patients with NK/T-cell lymphoid malignancy is the aforementioned PD-L1 expression in tumor cells of ENKTL and ANKL. In addition, the proven efficacy of pembrolizumab in relapsed or refractory ENKTL support the use of PD1 inhibitor as a salvage therapy for this disorder. The addition of isatuximab to cemiplimab might induce synergistic activity because CD38-mediated immunosuppression as a mechanism of tumor cell escape from PD-1/PD-L1 blockade. Furthermore, targeting CD38 by isatuximab can preferentially block immunosuppressive regulatory T-cells and thereby restore immune effector function against multiple myeloma. These functions of CD38 blocking antibody might help to improve the efficacy of immune checkpoint inhibitor such as PD1 inhibitor. Given the presence of antibody-mediated cytotoxicity and direct anti-tumor effect of isatuximab against CD38-positive tumor cells, the combination of isatuximab with cemiplimab might show the synergistic activity resulting more improved treatment outcome than PD1 inhibitor alone. Thus, The investigators designed a phase II study of cemiplimab and isatuximab for patients with relapsed or refractory ENKTL and ANKL. In this study, The investigators analyze the efficacy of this novel combination and their adverse effects.