Gastrointestinal toxicities associated with immune checkpoint inhibitors: a disproportionality analysis leveraging VigiBase, the WHO Adverse Drug Reaction Database

Focus on Immune Checkpoint Inhibitors-related Intestinal Inflammation: From Pathogenesis to Therapeutical Approach

Recently, antitumor immunotherapies have witnessed a breakthrough with the emergence of immune checkpoint inhibitors (ICIs) including programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors. Unfortunately, the use of ICIs has also led to the advent of a novel class of adverse events that differ from those of classic chemotherapeutics and are more reminiscent of autoimmune diseases, the immune-related adverse events (IRAEs). Herein, we performed an insight of the main IRAEs associated with ICIs, focusing on gastroenterological IRAEs and specifically on checkpoint inhibitor colitis, which represents the most widely reported IRAE to date. We comprehensively dissected the current evidence regarding pathogenesis, diagnosis, and management of ICIs-induced colitis, touching upon also on innovative therapies.

An unusual case of immune-related gastritis in one patient receiving toripalimab therapy

PD-1 inhibitors contribute to immune response against malignancies. These drugs also result in serial side effects. Here the authors report a case of immune-related gastritis induced by PD-1 inhibitor. A female with metastatic lung cancer developed severe epigastric pain and acid reflux during treatment with toripalimab. She underwent several gastroscopies, which showed progressively worse gastritis. After discontinuing toripalimab, those symptoms were resolved. This rare report highlights gastritis associated with toripalimab, describes the symptoms and histology features and records the progression of this side effect and the corresponding treatment. Based on the improvement after toripalimab withdrawal, the authors believed that she had autoimmune gastritis caused by toripalimab. This case reminds us that correct diagnosis and proper management are critical to patients undergoing treatment with PD-1 inhibitors.

Gastrointestinal injury induced by immunomodulators: A review article

An increasing number of immunomodulators, either anti-inflammatory or immunity-enhancing, have brought about a revolutionary effect in the management of a variety of autoimmune disorders and malignancies. However, their ability to cause gastrointestinal (GI) injury and induce GI symptoms has been increasingly and unexpectedly recognized. GI injury associated with immunomodulators may demonstrate various histologic and endoscopic patterns. Optimal diagnosis and treatment require a multidisciplinary approach. This review aims to provide an overview of the literature on its pathogenesis, the clinical, endoscopic, and histologic features, and suggested approaches to manage these newly recognized immunomodulator-induced GI adverse effects (AEs). We also reviewed current biomarkers predictive of GI toxicity and potential risk factors to identify susceptible patients. In addition, these immune-mediated AEs were compared with inflammatory bowel disease, a well-documented form of inflammation-driven GI injury. We hope this review will raise awareness and vigilance among clinicians of these entities to increase early diagnosis and rapid referral to specialist care.

Gastrointestinal perforation associated with novel antineoplastic agents: A real-world study based on the FDA Adverse Event Reporting System

Purpose: Gastrointestinal perforation (GIP) is a fatal adverse event (AE). The AE of GIP induced by novel antineoplastic agents has attracted attention recently. We aimed to explore the AE signals of GIP related to novel antineoplastic agents comprehensively based on the FDA Adverse Event Reporting System (FAERS). Methods: The FAERS database containing 71 quarters of records was used for analysis. Reporting odds ratio (ROR), information component (IC), and empirical Bayesian geometric mean (EBGM) were utilized to evaluate the signals of GIP associated with novel antineoplastic drugs. Standardization of drug names was by employing MedEx-UIMA software and Python. Data analysis and visualization were performed using MySQL Workbench and R software. Results: After cleaning and handling the data, 5226 GIP cases were identified that were associated with new antineoplastic medications, where these agents were the main suspected contributors. A total of 37 novel antineoplastic drugs were detected with signals of GIP for ROR and IC. Only 22 drugs showed statistically significant signals for EBGM. We found the GIP signals of 22 novel antineoplastic drugs overlapped for the 3 indicators, including anti-vascular endothelial growth factor/vascular endothelial growth factor receptor, anti-endothelial growth factor receptor, immune checkpoint inhibitors, and so on. Conclusion: The potential risk of GIP associated with several novel antineoplastic agents was identified through data mining, which provided valuable information on the safety risks associated with GIP among these drugs. The potential threat of GIP should be recognized and managed properly when using these novel antineoplastic agents.

Tumor immune checkpoints and their associated inhibitors

Immunological evasion is one of the defining characteristics of cancers, as the immune modification of an immune checkpoint (IC) confers immune evasion capabilities to tumor cells. Multiple ICs, such as programmed cell death protein-1 (PD-1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), can bind to their respective receptors and reduce tumor immunity in a variety of ways, including blocking immune cell activation signals. IC blockade (ICB) therapies targeting these checkpoint molecules have demonstrated significant clinical benefits. This is because antibody-based IC inhibitors and a variety of specific small molecule inhibitors can inhibit key oncogenic signaling pathways and induce durable tumor remission in patients with a variety of cancers. Deciphering the roles and regulatory mechanisms of these IC molecules will provide crucial theoretical guidance for clinical treatment. In this review, we summarize the current knowledge on the functional and regulatory mechanisms of these IC molecules at multiple levels, including epigenetic regulation, transcriptional regulation, and post-translational modifications. In addition, we provide a summary of the medications targeting various nodes in the regulatory pathway, and highlight the potential of newly identified IC molecules, focusing on their potential implications for cancer diagnostics and immunotherapy.

Ileus in patients treated with immune checkpoint inhibitors: A retrospective, pharmacovigilance study using Food and Drug Administration Adverse Event Reporting System database

OBJECTIVE

Immune checkpoint inhibitors (ICIs) have been widely used in cancer treatment; however, some case reports suggested that ICIs treatment might result in ileus. This study aims to comprehensively reveal the relationship between ileus and ICIs treatment in real-world cases from Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS).

METHODS

Reports from January 1, 2011 to December 31, 2020 were extracted from the FAERS. ICIs-related adverse events in patients were defined as related to use of anti-programmed cell death protein 1 antibodies (PD-1, nivolumab and pembrolizumab), anti-programmed cell death-ligand 1 inhibitors (PD-L1, atezolizumab, durvalumab, avelumab, and cemiplimab), and anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4, ipilimumab and tremelimumab). ICIs-related ileus cases were identified to characterize their clinical features. Reporting odds ratios (ROR) and information component (IC) were used to assess the relationship between ICIs and ileus.

RESULTS

Among the 105 001 cases related to ICIs, 245 were reported with ICI-related ileus. The affected patients were mainly elderly (median age, 64.5 years) and male (58%, n = 143). The median onset for all cases was 36 (range 0-880) days, and no statistical difference was observed between monotherapy and combination therapy (PD-1 or PD-L1 plus CTLA-4) (p = 0.21). Most patients required drug withdrawal treatment (n = 113, 74%) and can achieve a recovered-resolved state (n = 72, 46%). All ICIs were significantly associated with ileus (ROR = 4.27, 95%Cl: 3.75-4.85; IC = 2.04, 95%Cl: 1.79-2.31). Ileus events were most commonly reported in PD-1 treatment (n = 164, ROR = 3.83, 95%Cl: 3.28-4.48; IC = 1.90, 95%Cl: 1.62-2.21).

CONCLUSION

This pharmacovigilance database analysis suggested that ICIs are related to ileus. However, combination therapy may not speed up the onset of ileus.