{
  "abstract": "Background As the proportion of cancer patients eligible for immune checkpoint inhibitor (ICI) treatments has increased over the past decade, 1 2 the importance of assessing their benefit-risk balance has grown correspondingly. Despite the clinical benefits, the use of ICI carries the risk of toxicity such as immune-related adverse events (irAEs). If left unmanaged, irAEs can compromise treatment efficacy and may even lead to serious morbidity and mortality.3 4 Although various sources provide safety data on ICI treatments, the reported incidence of irAEs may not always be consistent across them.Methods We analyzed 36 severe irAEs across clinical trial and real-world datasets to assess reporting discrepancies. irAE data were collected from 54 clinical trials that supported FDA approval of nine ICI drugs, resulting in 61 unique trial-treatment combinations. Only data with matched participant counts (n = 19,799) between ClinicalTrials.gov and corresponding published literature were included, allowing for the direct comparison of irAE counts. Real-world adverse event data from 65,555 cancer patients were obtained from the FDA Adverse Event Reporting System (FAERS). Relative odds ratios (RORs) were calculated to evaluate the association between specific treatments and irAEs in both ClinicalTrials.gov and FAERS. Concordance between these data sources was assessed using Cohen’s kappa score, with statistical significance evaluated through permutation testing.Results Between literature and ClinicalTrialsgov, direct comparison of reported irAE counts showed inconsistencies for 35 out of 36 irAEs. Of these, 35 irAEs were under-reported in literature, whereas 22 were over-reported in at least one trial-treatment combination. When analyzing proportions of misreporting across trials, 31 irAEs were more frequently under-reported in the literature, and 4 were more frequently over-reported. In comparison with FAERS data, arthralgia was the most over-reported irAE in ClinicalTrials.gov (7/9 drug treatments), while adrenal insufficiency was the most under-reported (4/9 drug treatments). Between ClinicalTrials.gov and FAERS, 27 out of 36 irAEs showed low concordance (kappa score < 0.2), while hypophysitis, infusion reactions, and colitis showed moderate but significant concordance.Conclusions Direct comparison of irAE counts between literature and ClinicalTrials.gov revealed frequent discrepancies, with a tendency toward under-reporting in the literature, despite both sources reporting on the same clinical trials. These findings highlight the need for improved consistency in reporting adverse events from clinical trials. Moreover, irAE reporting in clinical trials is not always concordant with real-world data, which may affect ICI treatment decisions for individual patients in a real-world clinical setting.References Haslam A, Olivier T, Prasad V. How many people in the are eligible for and respond to checkpoint inhibitors: an empirical analysis . Int J Cancer. 2025 Jun 15;156(12):2352–9.Prasad V, Haslam A, Olivier T. Updated estimates of eligibility and response: immune checkpoint inhibitors. Journal of Clinical Oncology [Internet]. 2024 Jun 1 [cited 2025 Feb 11];42(16_suppl):e14613-e1461Available from: https://ascopubs.org/doi/10.1200/JCO.2024.42.16_suppl.e14613 3. Schneider BJ, Naidoo J, Santomasso BD, Lacchetti C, Adkins S, Anadkat M, et al. Management of immune-related adverse events in patients treated with immune checkpoint inhibitor therapy: ASCO guideline update. Journal of Clinical Oncology [Internet]. 2021 Dec 20 [cited 2025 Feb 11];39(36):4073–126. Available from: https://ascopubs.org/doi/10.1200/JCO.21.01440Naidoo J, Johnson DB, Doran C, Wang Y, Zhang Y, Le TK, et al. Management of severe immune-related adverse events and outcomes in patients with advanced non-small cell lung cancer receiving immune checkpoint inhibitors. Oncologist. 2024 Nov 20.",
  "authors": [
    {
      "affiliations": [
        "University of Utah, Salt Lake City, UT, USA"
      ],
      "name": "Olivia Cheng"
    },
    {
      "affiliations": [
        "University of Utah, Salt Lake City, UT, USA"
      ],
      "name": "Emily Tan"
    },
    {
      "affiliations": [
        "University of Utah, Salt Lake City, UT, USA"
      ],
      "name": "David Stone"
    },
    {
      "affiliations": [
        "University of Utah, Salt Lake City, UT, USA"
      ],
      "name": "Xi Qiao"
    },
    {
      "affiliations": [
        "University of Utah, Salt Lake City, UT, USA"
      ],
      "name": "Arabella Young"
    },
    {
      "affiliations": [
        "Huntsman Cancer Institute, Salt Lake City, UT, USA"
      ],
      "name": "Aik Choon Tan"
    }
  ],
  "title": "1058 Evaluating the reporting discrepancies of immune-related adverse events between clinical trials and real-world data for immune checkpoint inhibitors",
  "uid": "a7c14c9e-d8f8-56cd-b72d-5689369b60d7"
}