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.
Keywords: Nivolumab; complete response; head and neck; immune-related adverse event; squamous cell carcinoma.