Five Cases of Cytokine Release Syndrome in Patients Receiving Cytotoxic Chemotherapy Together With Nivolumab Plus Ipilimumab: A Case Report

We conducted a phase 3 clinical trial to compare the effi- cacy of platinum-based combination chemotherapy together with nivolumab plus ipilimumab relative to that of platinum-based combination chemotherapy together with pembrolizumab in previously untreated patients with advanced NSCLC. The trial was terminated prematurely after treatment of 295 patients because of a high proportion of treatment-related deaths, three of which were due to cytokine release syndrome (CRS), in the nivolumab plus ipilimumab treatment arm. In addition, we encountered two cases of CRS that were effectively managed, for a total of five cases (3.4%) among the 148 patients in the nivolumab plus ipilimumab arm. We here provide details of these five cases. Although patient background and timing of CRS onset differed, fever was observed before the emergence of CRS in all five cases. Oncologists should thus be aware that the development of fever during treatment of patients with nivolumab plus ipilimumab may herald the onset of CRS.