Introduction: Little evidence exists on the safety and efficacy of the rechallenge of immune checkpoint inhibitors (ICIs) after immune-related adverse events (irAEs) in patients with cancer.
Methods: We searched PubMed, Web of Science, Embase, and Cochrane for articles on ICI rechallenge after irAEs for systemic review and meta-analysis. The outcomes included the incidence and associated factors for safety and objective response rate (ORR) and disease control rate (DCR) for efficacy.
Results: A total of 789 ICI rechallenge cases from 18 cohort studies, 5 case series studies, and 54 case reports were included. The pooled incidence of all-grade and high-grade irAEs after rechallenge in patients with cancer was 34.2% and 11.7%, respectively. Compared with initial ICI treatment, rechallenge showed a higher incidence for all-grade irAEs (OR, 3.81; 95% CI, 2.15-6.74; p < 0.0001), but similar incidence for high-grade irAEs (p > 0.05). Types of initial irAEs (pneumonitis and global irAEs) and cancer (non-small cell lung cancer and multiple cancer) recapitulated these findings. Gastrointestinal irAEs and time interval between initial irAEs and ICI rechallenge were associated with higher recurrence of high-grade irAEs (p < 0.05), whereas initial anti-PD-1/PD-L1 antibodies were associated with a lower recurrence (p < 0.05). Anti-PD-1/PD-L1 antibodies rechallenge was associated with a lower all-grade irAE recurrence (p < 0.05). The pooled ORR and DCR after rechallenge were 43.1% and 71.9%, respectively, showing no significant difference compared with initial ICI treatment (p > 0.05).
Conclusions: ICI rechallenge after irAEs showed lower safety and similar efficacy outcomes compared with initial ICI treatment.
Systematic review registration: PROSPERO, identifier CRD42020191405.
Keywords: cancer; efficacy; immune checkpoint inhibitors; immune-related adverse events; rechallenge; safety.
Copyright © 2021 Zhao, Zhang, Xu, Yang, Liang, Zhang, Zhang and Zhang.