Immune checkpoint inhibitor rechallenge after immune-related adverse events: a retrospective study from VigiBase update in 2024 looking for emergent safety signals.

Abstract

Limited information is available on the safety of a rechallenge with an immune checkpoint inhibitor (ICI) after occurrence of an immune-related adverse event (irAE). We aim to identify potential emergent safety signals. This is an update of our observational pharmacovigilance cohort study. We exanimated individual case safety reports from the WHO database VigiBase. We included all individual case safety reports with ICI and rechallenged ICI. We identified that incident irAE cases using the Medical Dictionary for Regulatory Activities V.26.1 related with at least one ICI administration were systematically collected until 1 March 2024. The primary outcome was the recurrence rate (expressed as a percentage with its 95% CI) of the initial irAE postrechallenge with the same ICI. We identified 1016 irAEs cases from ICI rechallenges. Of these, 323 irAEs recurrences occurred (31.8%, 95% CI 28.1 to 34.0). The most common postrechallenge irAEs were nephritis (recurrence rate: 50%, 95% CI 25 to 75), skin irAEs (44%, 95% CI 31 to 58) and colitis (39%, 95% CI 33 to 44). In this updated, largest cohort study on rechallenge (NCT04696250), we observed a 31.8% recurrence rate of the same irAE postrechallenge with the same ICI, building on our previous findings. NCT04696250.