Skin toxicity associated with immune checkpoint inhibitors based on the FDA adverse event reporting system 2011 – 2023 data

To evaluate skin toxicity associated with immune checkpoint inhibitors (ICIs) using data mining and the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). Data on skin toxicity associated with the use of ICIs were retrieved for the period January 2011 to September 2023. Analysis was done using various methods, including reporting odds ratio (ROR) estimates, proportional reporting ratios (PRR), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker estimates (MGPS). Mortality and hospitalization data were also assessed. A total of 8,129 skin toxicity reports concerning "ICIs" as the "primary suspected cause" were documented, accounting for 18.89% of all reported adverse events. Anti-PD-1 agents showed the highest incidence of skin toxicity, whereas anti-CTLA-4 monotherapy was associated with the most significant changes in ROR, PRR, empirical Bayesian geometric mean (EBGM), and information component (IC) values. The median onset of toxicity was 17 days after commencement of ICI treatment, consistent across sexes, age groups, and ICI types. The highest mortality rate occurred with anti-PD-1 treatment (11.37%), and there was a significant difference in mortality rates between different ICI treatments (monotherapy vs. combination therapy) (p = 0.03). Differences are present between ICI regimens in the pattern of skin toxicity with anti-PD-1 therapies exhibiting the highest incidence of skin toxicity and mortality rates, while anti-CTLA-4 therapies showed the most marked signals.