Risk factors and prognostic role of renal adverse event in patients receiving immune checkpoint inhibitor therapy: analysis of data from a retrospective cohort study.

Background: Along with the widespread use of immune checkpoint inhibitors (ICIs), there has been a surge in immune-related adverse events which can limit the efficacy of ICIs. However, to date, there is a paucity of reports on renal adverse events (RAEs) related to ICIs. Therefore, this study reports the incidence, risk factors, pathological features of RAEs in patients receiving ICI therapy and its association with overall survival. Methods: The medical records of patients who received at least 1 cycle of anti-programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) monoclonal antibody (mAb) between January 1st 2018 and July 31th 2021 were retrospectively reviewed. All available serum creatinine data were extracted and used to calculate the estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and RAEs were defined as a 25% decrease in eGFR from baseline. Logistic regression was used to analyze the risk factors for RAEs. The Kaplan-Meier method was used to compare the survival among patients with and without RAEs. Results: A total of 328 patients receiving ICI therapy were enrolled and 42 developed RAEs. Patients with RAEs had a lower median baseline acute monocyte count (AMC), higher median baseline ratio of lymphocyte and monocyte (LMR), were more likely to have hypertension, coronary heart disease, and distant metastasis, and were more likely to be receiving more cycles of ICI therapy. Multivariate analysis revealed that RAEs were associated with distant metastasis and the number of cycles of ICI therapy. RAEs were not associated with baseline creatinine, eGFR, ICI type, nor the line of ICI therapy. Regardless of whether patients were receiving first-line ICI therapy or non-first line ICI therapy, patients with RAEs had lower survival rates compared to patients without RAEs. Of the patients with RAEs, 2 received renal biopsies and were pathologically confirmed with acute interstitial nephritis (AIN). Conclusions: RAEs were not a rare complication in patients receiving ICIs treatment. Distant metastasis and the number of cycles of ICI therapy were associated with RAEs. Patients who developed RAEs were associated with worse survival.