Abstract
<jats:sec> <jats:title>Purpose</jats:title> <jats:p>This study aimed to characterize FAERS reports of immune-mediated upper gastrointestinal (GI) toxicities associated with immune checkpoint inhibitors and to explore disproportional reporting patterns across ICI classes and treatment regimens.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Input data were downloaded from the public release of the FDA database including time period between January 1 2016, and December 31, 2024. 132 patients with upper-GI toxicity were included. Categorical variables were compared using either the chi-square test or Fisher's exact test. To evaluate the potential association between ICIs and specific upper-GI toxicity events of interest, a disproportionality analysis was conducted using the Reporting Odds Ratio (ROR) method. A signal was considered statistically significant when the lower bound of the 95% confidence interval for the ROR exceeded 1.0.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Anti-PD-1 agents showed higher disproportional reporting of upper-GI toxicities compared to anti-PD-L1 (p = 0.001, ROR = 3.83 95% CI: 1.53–15.23). A higher proportion of hospitalization among reported cases were observed in patients treated with concurrent chemotherapy, compared to those did not receive chemotherapy (ROR = 2.5; 95% CI: 1.05–5.921; p = 0.045).</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusion</jats:title> <jats:p>Anti-PD-1 therapy showed a stronger reporting signal for upper-GI toxicity than anti-PD-L1 therapy in FAERS, although the number of anti-PD-L1 cases was small. Concurrent chemotherapy was associated with a higher proportion of hospitalization among reported cases. These findings are exploratory and hypothesis-generating.</jats:p> </jats:sec>