Enfortumab Vedotin-Induced Febrile Neutropenia and Hyperglycemia Successfully Treated with Multidisciplinary Treatment Including Continuous Hemodialysis Filtration and Insulin Injection in a Patient with Chemo-Resistant Metastatic Urothelial Carcinoma: A Case Report.

Introduction: Enfortumab vedotin (EV) is an antibody-drug conjugate combining a monoclonal antibody targeting nectin-4 with a highly potent microtubule disrupting agent. EV is expected to be a candidate for the third-line treatment for urothelial carcinoma previously treated with platinum-based chemotherapy and PD-1/PD-L1 inhibitors. Very few cases of patients experienced hyperglycemia of unknown cause.

Case presentation: We describe a 72-year-old Asian man with mild obesity, type 2 diabetes, hyperlipidemia, hypertension, and chemo-resistant metastatic urothelial carcinoma. He developed hyperglycemia and febrile neutropenia after 3 doses of EV. He had hyperglycemia of 489 mg/dL and was started on continuous intravenous insulin infusion (CVII). The patient's intravenous insulin requirements peaked at 316 units per day. He also developed febrile neutropenia and consequent sepsis caused acute kidney injury. Continuous hemodialysis filtration (CHDF) together with antibiotics were started to treat the septic condition. The blood glucose level gradually decreased after CHDF treatment and CHDF was continued for 14 days. The timing of liberation from CHDF correlated with the elimination half-life of EV of 3.4 days. CVII was treated for 26 days and the patient was finally released from the intensive care unit.

Conclusion: This case indicates that the uncontrollable hyperglycemia induced by EV during metastatic urothelial carcinoma treatment is effectively managed with CVII and CHDF until the elimination of the adverse effect of EV.