The Pattern of Time to Onset and Resolution of Immune-Related Adverse Events Caused by Immune Checkpoint Inhibitors in Cancer: A Pooled Analysis of 23 Clinical Trials and 8,436 Patients

The occurrence pattern of immune-related adverse events (irAEs) induced by immune checkpoint inhibitor (ICI) in cancer treatment remains unclear. Phase II-III clinical trials that evaluated ICI-based treatments in cancer and were published between January 2007 and December 2019 were retrieved from public electronic databases. The pooled median time to onset (PMT-O), resolution (PMT-R), and immune-modulation resolution (PMT-IMR) of irAEs were generated using the metamedian package of R software. Twenty-two eligible studies involving 23 clinical trials and 8,436 patients were included. The PMT-O of all-grade irAEs ranged from 2.2 to 14.8 weeks, with the longest in renal events. The PMT-O of grade ≥ 3 irAEs was significantly longer than that of all-grade irAEs induced by programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1) inhibitors (27.5 weeks vs. 8.4 weeks, p < 0.001) and treatment of nivolumab (NIV) plus ipilimumab (IPI) (7.9 weeks vs. 6.0 weeks, p < 0.001). The PMT-R of all-grade irAEs ranged from 0.1 to 54.3 weeks, with the shortest and longest in hypersensitivity/infusion reaction and endocrine events, respectively. The PMT-IMR of grade ≥ 3 irAEs was significantly shorter than that of all-grade irAEs caused by PD-1/PD-L1 blockade (6.9 weeks vs. 40.6 weeks, p=0.002) and NIV+IPI treatment (3.1 weeks vs. 5.9 weeks, p=0.031). This study revealed the general and specific occurrence pattern of ICI-induced irAEs in pan-cancers, which was deemed to aid the comprehensive understanding, timely detection, and effective management of ICI-induced irAEs.