Efficacy and predictors of rechallenge with immune checkpoint inhibitors in non‐small cell lung cancer

BACKGROUND: The efficacy of rechallenge with immune checkpoint inhibitors (ICIs) in non‐small cell lung cancer (NSCLC) patients has not yet been fully clarified. This study aimed to identify the clinical characteristics of patients with NSCLC who benefited from rechallenge with ICIs. METHODS: We retrospectively reviewed the clinical records of 24 patients who were diagnosed with NSCLC and rechallenged with ICIs between August 2016 and July 2021. RESULTS: Of the 24 patients included in the study, 11 were in the responder group (45.8%) and 13 in the nonresponder group (54.2%). The number of patients who used a different ICI from that used in the initial therapy was significantly higher in the responder group than in the nonresponder group (p = 0.006). Multivariate analysis identified lung metastasis and female sex as significant independent risk factors for nonresponse to rechallenge with ICIs. Compared to the nonresponder group, the duration of treatment after rechallenge with ICIs was significantly longer in the responder group (p = 0.016), and there was a trend toward longer overall survival (p = 0.059). CONCLUSIONS: Patients with lung cancer who were rechallenged with ICIs and without progressive disease after initial ICI therapy were able to continue ICI therapy for a longer period of time. This may be associated with longer survival. Patients with lung metastases and female patients are more likely to be nonresponsive to rechallenge with ICIs. Administration of a different type of ICI from that used in the initial ICI therapy may result in disease control.