Successful Treatment of Diffuse Large B-Cell Lymphoma and Antisynthetase Syndrome with Bispecific Antibody Glofitamab.

Glofitamab, a CD20×CD3 T-cell-engaging bispecific monoclonal antibody, has emerged as a promising therapeutic agent for relapsed/refractory B-cell non-Hodgkin lymphoma. The advent of chimeric antigen receptor T-cell therapy and T-cell-engaging bispecific antibodies has also stimulated growing interest in their potential application in autoimmune diseases. Here, we report a case of diffuse large B-cell lymphoma (DLBCL) in a patient with a long-standing history of antisynthetase syndrome (ASyS). The patient achieved complete remission of lymphoma with third-line glofitamab therapy after failure of first-line R-CHOP and second-line polatuzumab vedotin combined with lenalidomide. Remarkably, her ASyS symptoms, which had been refractory to multiple immunosuppressive agents (cyclosporine, methotrexate, hydroxychloroquine) and targeted therapies (tofacitinib, baricitinib), also resolved following glofitamab treatment. This case underscores the potential of glofitamab not only as an effective treatment for refractory DLBCL but also as a novel therapeutic strategy for concomitant autoimmune manifestations, warranting further investigation in the context of autoimmune disorders.