The therapeutic landscape for relapsed/refractory diffuse large b-cell lymphoma (R/R DLBCL) is expanding, with bispecific antibodies emerging as key treatment strategies. These drugs have demonstrated high efficacy in this setting of patient, but leading to prolonged immunosuppression, exposing patients to a high risk of infections. We describe a R/R DLBCL patient achieving complete remission (CR) with glofitamab, although discontinued due to JC virus reactivation. Nineteen months post-treatment, the patient remains in CR, with declining viral copies and no evidence of neurological complications. The patient also has a history of chronic myeloid leukemia (CML), currently in treatment free remission (TFR). This is an example of durable DLBCL remission despite abbreviated glofitamab therapy, while highlighting challenges in balancing immunotherapy efficacy with opportunistic infection risks.