Clinical outcome in recurrent and/or metastatic head and neck cancer patients after discontinuation of nivolumab monotherapy due to immune-related adverse events.

BACKGROUND Significant immune-related adverse events (irAEs) requiring therapy discontinuation sometimes occur. The influence of discontinuation on disease control after an irAE is unclear. OBJECTIVES The aim of this study was to investigate whether or not patients continued to show a response or durable disease control even after stopping therapy following an irAE. MATERIAL AND METHODS The response after nivolumab monotherapy discontinuation was examined for 14 patients in whom therapy was stopped without progression. RESULTS The best response was CR in 5 (36%) patients, PR in 8 (57%) patients and SD in 1 (7%) patient. The estimated 1-year overall and progression-free survival rates were 92.9% and 78.6%, respectively. The best response during nivolumab therapy in patients who developed PD was CR in 0 of 5 patients (0%), PR in 3 of 8 patients (38%) and SD in 1 patient (100%). Patients obtaining CR tended to have a lower risk of PD than those with PR or SD. CONCLUSIONS AND SIGNIFICANCE Patients with CR status may continue to show a response or durable disease control even after stopping therapy due to an irAE.