Multiple immune-related adverse events secondary to checkpoint inhibitor therapy in patients with advanced cancer: association with treatment effectiveness.

Introduction: Checkpoint inhibitors (CPI) are widely used in cancer treatment with a potential of causing immune-related adverse events (IRAEs). Several studies have reported a positive correlation between development of IRAEs and improved survival outcome. However, few studies have focused on the potential role of multiple IRAEs on treatment effectiveness. This study aimed at investigating the association between multiple IRAEs and treatment effectiveness in terms of progression-free survival (PFS) and overall survival (OS) in advanced cancer patients. Methods: We performed a retrospective cohort study at three Swedish centers. All patients (n=600) treated with PD-L1 or PD-1 inhibitor, in monotherapy or in combination for advanced cancer between January 2017 and December 2021 were included. Multiple IRAEs were defined as IRAEs involving more than one organ system either simultaneously or sequentially. Time-depending Cox-regression model to mitigate the risk for immortal time bias (ITB) was applied. Results: The major tumor types were non-small cell lung cancer (205 patients; 34.2%) and malignant melanoma (196 patients; 32.7%). Of all patients,32.8% developed single IRAE and 16.2% multiple IRAEs. Patients with multiple IRAEs showed significantly improved PFS (Hazard Ratio, HR=0.78 95% Confidence Interval, CI: 0.57-0.98) and OS (HR=0.65 95% CI: 0.44-0.95) compared to patients with single IRAE or no IRAE (HR=0.46 95% CI:0.34-0.62 for PFS vs HR=0.41 95% CI: 0.28-0.60 for OS). Conclusion: In conclusion, our data supports a stronger association between development of multiple as opposed to single IRAEs and clinical effectiveness in advanced cancer patients treated with CPIs.

Predicting immune-related adverse events using a simplified frailty score in cancer patients treated with checkpoint inhibitors: A retrospective cohort study.

OBJECTIVE: Checkpoint inhibitors (CPIs) are in widespread clinical use. Little is known about which patients are at risk for developing toxicity. It is essential being able to identify patients with higher risk of experiencing immune-related adverse events (IRAEs) before initiation of CPI treatment to optimize treatment decisions and follow-up strategy. The aim of this study was to investigate whether a simplified frailty score based on performance status (PS), age, and comorbidity expressed as Charlson comorbidity index (CCI) could predict development of IRAEs. METHODS: We performed a retrospective cohort study at three Swedish centers. All patients (n = 596) treated with PD-L1 or PD-1 inhibitor for advanced cancer between January 2017 and December 2021 were included. RESULTS: In total, 361 patients (60.6%) were classified as nonfrail and 235 (39.4%) as frail. The most common cancer type was non-small cell lung cancer (n = 203; 34.1%) followed by malignant melanoma (n = 195; 32.7%). Any grade of IRAE occurred in 138 (58.7%) frail and in 155 (42.9%) non-frail patients (OR: 1.58; 95% CI: 1.09-2.28). Age, CCI, and PS did not independently predict the occurrence of IRAEs. Multiple IRAEs occurred in 53 (22.6%) frail and in 45 (12.5%) nonfrail patients (OR: 1.62; 95% CI: 1.00-2.64). DISCUSSION: In conclusion, the simplified frailty score predicted all grade IRAEs and multiple IRAEs in multivariate analyses whereas age, CCI, or PS did not separately predict development of IRAEs suggesting that this easy-to-use score may be of value in clinical decision making but a large prospective study is needed to assess its true value.