Immune checkpoint inhibitor-induced interstitial lung disease with and without CTLA-4 regimen in non-small cell lung cancer patients and PD-L1 < 1 %: A multicenter, retrospective study.

Background: For patients with advanced or recurrent non-small cell lung cancer (NSCLC) and PD-L1 < 1 %, a combination of an anti-CTLA-4 and anti-PD-1 antibody with and without platinum-based chemotherapy are used as a first-line treatment. Although the combined use of anti-CTLA-4 antibody has favorable therapeutic efficacy, increased incidence and severity of immune-related adverse events, including immune checkpoint inhibitor-induced interstitial lung disease (ICI-ILD), remains a challenge.

Methods: A multicenter retrospective study of patients with advanced or recurrent NSCLC and PD-L1 < 1 % who received immune checkpoint inhibitors as a first-line treatment. The primary and secondary endpoints were incidence and prognostic impact, respectively, of ICI-ILD.

Results: The cohort included 376 patients, with 119 and 257 receiving a CTLA-4 regimen and non-CTLA-4 regimen, respectively. The ICI-ILD incidence tended to be higher in patients treated with the CTLA-4 regimen, but the difference from the non-CTLA-4 regimen was not significant. Patients with ICI-ILD treated with the CTLA-4 regimen tended to have longer progression-free survival and overall survival than those who received non-CLTLA-4 treatment, but the difference was not significant.

Conclusion: For patients with NSCLC and PD-L1 < 1 %, the incidence of ICI-ILD tended to be higher in CTLA-4 regimens, and survival of patients with ICI-ILD tended to be longer for CTLA-4 regimens than for non-CTLA-4 regimens. Although the incidence of ICI-ILD in patients given CTLA-4 regimens tended to be higher than in those given non-CTLA-4 regimens, development of ICI-ILD does not necessarily negatively impact survival.