Colitis after checkpoint blockade: A retrospective cohort study of melanoma patients requiring admission for symptom control

Defining D-irAEs: consensus-based disease definitions for the diagnosis of dermatologic adverse events from immune checkpoint inhibitor therapy

With an increasing number of patients eligible for immune checkpoint inhibitors, the incidence of immune-related adverse events (irAEs) is on the rise. Dermatologic immune-related adverse events (D-irAEs) are the most common and earliest to manifest, often with important downstream consequences for the patient. Current guidelines lack clarity in terms of diagnostic criteria for D-irAEs. The goal of this project is to better define D-irAE for the purposes of identification, diagnosis, and future study of this important group of diseases.The objectives of this project were to develop consensus guidance for an approach to D-irAEs including disease definitions and severity grading. Knowing that consensus among oncologists, dermatologists, and irAE subspecialists would be critical for usability, we formed a Dermatologic irAE Disease Definition Panel. The panel was composed of 34 experts, including oncologists, dermatologists, a rheumatologist, and an allergist/immunologist from 22 institutions across the USA and internationally. A modified Delphi consensus process was used, with two rounds of anonymous ratings by panelists and two virtual meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness, and accuracy on 9-point scales in electronic surveys and provided free text comments. A working group aggregated survey responses and incorporated them into revised definitions. Consensus was based on numeric ratings using the RAND/UCLA Appropriateness Method with prespecified definitions.Following revisions based on panelist feedback, all items received consensus in the second round of ratings. Consensus definitions were achieved for 10 core D-irAE diagnoses: ICI-vitiligo, ICI-lichen planus, ICI-psoriasis, ICI-exanthem, ICI-bullous pemphigoid, ICI-Grover's, ICI-eczematous, ICI-eruptive atypical squamous proliferation, ICI-pruritus without rash, and ICI-erosive mucocutaneous. A standard evaluation for D-irAE was also found to reach consensus, with disease-specific exceptions detailed when necessary. Each disorder's description includes further details on disease subtypes, symptoms, supportive exam findings, and three levels of diagnostic certainty (definite, probable, and possible).These consensus-driven disease definitions standardize D-irAE classification in a useable framework for multiple disciplines and will be the foundation for future work. Given consensus on their accuracy and usability from a representative panel group, we anticipate that they can be used broadly across clinical and research settings.

Management of liver and gastrointestinal toxicity induced by immune checkpoint inhibitors: Position statement of the AEEH-AEG-SEPD-SEOM-GETECCU

The development of the immune checkpoint inhibitors (ICI) is one of the most remarkable achievements in cancer therapy in recent years. However, their exponential use has led to an increase in immune-related adverse events (irAEs). Gastrointestinal and liver events encompass hepatitis, colitis and upper digestive tract symptoms accounting for the most common irAEs, with incidence rates varying from 2% to 40%, the latter in patients undergoing combined ICIs therapy. Based on the current scientific evidence derived from both randomized clinical trials and real-world studies, this statement document provides recommendations on the diagnosis, treatment and prognosis of the gastrointestinal and hepatic ICI-induced adverse events.

Updates in the pathogenesis and management of immune-related enterocolitis, hepatitis and cardiovascular toxicities

Immune checkpoint inhibitors (ICIs) have become a cornerstone of treatment for many solid organ malignancies. Alongside increasing use, the occurrence of immune-related adverse events (irAEs) has also increased and remains a significant challenge when treating patients with ICI. The underlying pathophysiology of irAE development for many organ systems is yet to be elucidated, but may involve unmasking of latent autoimmunity, increased T-cell recognition of shared antigens on cancer and normal tissue and ICI-triggered immune dysregulation with overactivation of proinflammatory pathways and suppression of immune control pathways. Management strategies for irAEs have historically been borrowed from paradigms for conventional autoimmune conditions such as inflammatory bowel disease and autoimmune hepatitis; however, recent translational efforts have clearly demonstrated key differences in underlying immune signalling pathways. As we begin to understand these differences, we must adapt a more targeted approach to immunosuppression and exercise a more nuanced approach with the multiple biologic agents available to mitigate ICI-related toxicity without reversing the antitumour effect of ICI. In this review, we focus on three key immune-related toxicities where recent clinical and translational work has provided nuanced insights into pathogenesis and treatment strategies: enterocolitis, hepatitis and cardiovascular toxicity including myocarditis.

Management of liver and gastrointestinal toxicity induced by immune checkpoint inhibitors: Position statement of the AEEH-AEG-SEPD-SEOM-GETECCU

The development of the immune checkpoint inhibitors (ICI) is one of the most remarkable achievements in cancer therapy in recent years. However, their exponential use has led to an increase in immune-related adverse events (irAEs). Gastrointestinal and liver events encompass hepatitis, colitis and upper digestive tract symptoms accounting for the most common irAEs, with incidence rates varying from 2 % to 40 %, the latter in patients undergoing combined ICIs therapy. Based on the current scientific evidence derived from both randomized clinical trials and real-world studies, this statement document provides recommendations on the diagnosis, treatment and prognosis of the gastrointestinal and hepatic ICI-induced adverse events.

Treatment and outcomes of immune checkpoint inhibitors-associated colitis/diarrhea: A systematic review and meta-analysis

BACKGROUND

Immune checkpoint inhibitors (ICIs) have improved the outcomes of cancer patients. However, ICIs often lead to colitis/diarrhea. This study aimed to assess the treatment of ICIs-associated colitis/diarrhea and outcomes.

METHODS

PubMed, EMBASE, and Cochrane Library databases were searched for eligible studies which investigated the treatment and outcomes of colitis/diarrhea developing in patients who received ICIs. The pooled incidences of any-grade colitis/diarrhea, low-grade colitis, high-grade colitis, low-grade diarrhea, and high-grade diarrhea as well as the pooled rates of response to treatment, mortality, and ICIs permanent discontinuation and restarts in patients with ICIs-associated colitis/diarrhea were estimated using a random-effects model.

RESULTS

Among the 11,492 papers initially identified, 27 studies were included. The pooled incidences of any-grade colitis/diarrhea, low-grade colitis, high-grade colitis, low-grade diarrhea, and high-grade diarrhea were 17%, 3%, 17%, 13%, and 15%, respectively. The pooled rates of overall response, response to corticosteroid therapy, and response to biological agents were 88%, 50%, and 96%, respectively. The pooled short-term mortality in patients with ICIs-associated colitis/diarrhea was 2%. The pooled incidences of ICIs permanent discontinuation and restarts were 43% and 33%, respectively.

CONCLUSION

ICIs-associated colitis/diarrhea is common, but rarely lethal. Half of them are responsive to corticosteroid therapy. There is a fairly high rate of response to biological agents in steroid-refractory colitis/diarrhea patients.

Moderate Colitis Not Requiring IV Steroids Is Associated with Improved Survival in Stage IV Melanoma after Anti-CTLA4 Monotherapy, But Not Combination Therapy

Background

For patients with melanoma, gastrointestinal immune-related adverse events are common after receipt of anti-CTLA4 therapy. These present difficult decision points regarding whether to discontinue therapy. Detailing the situations in which colitis might predict for improved survival and how this is affected by discontinuation or resumption of therapy can help guide clinical decision-making.

Materials and Methods

Patients with stage IV melanoma receiving anti-CTLA4 therapy from 2008 to 2019 were analyzed. Immune-related colitis treated with ≥50 mg prednisone or equivalent daily or secondary immunosuppression was included. Moderate colitis was defined as receipt of oral glucocorticoids only; severe colitis was defined as requiring intravenous glucocorticoids or secondary immunosuppression. The primary outcome was overall survival (OS).

Results

In total, 171 patients received monotherapy, and 91 received dual checkpoint therapy. In the monotherapy group, 25 patients developed colitis and a nonsignificant trend toward improved OS was observed in this group. Notably, when colitis was categorized as none, moderate or severe, OS was significantly improved for moderate colitis only. This survival difference was not present after dual checkpoint therapy. There were no differences in known prognostic variables between groups, and on multivariable analysis neither completion of all ipilimumab cycles nor resumption of immunotherapy correlated with OS, while the development of moderate colitis did significantly affect OS.

Conclusion

This single-institution retrospective series suggests moderate colitis correlates with improved OS for patients with stage IV melanoma treated with single-agent anti-CTLA4, but not dual agent, and that this is true regardless of whether the immune-checkpoint blockade is permanently discontinued.

Systematic review: disease activity indices for immune checkpoint inhibitor-associated enterocolitis

BACKGROUND

Although there is interest in developing pharmacotherapies for the treatment of immune checkpoint inhibitor-associated enterocolitis (ICIC), there is currently no consensus on how to optimally measure disease activity in this condition.

AIMS

To identify all scoring indices used for the measurement of disease activity in ICIC, assess their operating properties, and explore their potential utility as outcome measures.

METHODS

We searched MEDLINE, EMBASE and the Cochrane Library from inception to November 2020 to identify studies that evaluated disease activity and severity in patients with ICI-associated enterocolitis. These scoring tools could be designed specifically for ICIC or adapted from other diseases, and assessed clinical, endoscopic, or histologic disease activity.

RESULTS

Sixty-four studies were included. The Common Terminology Criteria for Adverse Events is commonly used to describe symptoms, although has only been partially validated and was not designed as a disease activity index. Endoscopic and histologic indices used in inflammatory bowel disease have been adopted for ICIC including the Mayo Endoscopic Subscore, Ulcerative Colitis Endoscopic Index of Severity, Simple Endoscopic Score for Crohn's Disease, Nancy Histological Index, Robarts Histopathological Index, and Geboes Score, among others. None of these indices has been validated for use in ICIC, and all lacked content validity and responsiveness.

CONCLUSIONS

There are no validated clinical, endoscopic, or histologic outcomes to assess disease activity in ICIC. Development and validation of reliable and responsive outcome measures that can be used to measure disease activity will be paramount for both clinical practice and for the development of treatments.

Update on Immune Checkpoint Inhibitor Enterocolitis

PURPOSE OF REVIEW

Immune checkpoint inhibitor (ICI) therapy revolutionized the treatment of multiple solid and hematologic malignancies. Yet, with it came profound inflammatory toxicities that mimic autoimmune diseases, termed immune-related adverse events (irAEs). Prominent among these is gastrointestinal inflammation, including a spectrum of gastritis, enteritis, and colitis. Here we synthesize an approach to immune checkpoint related enterocolitis (irEC) - including diagnostics and therapeutics - underpinned by new insights into the mechanism behind these phenomena.

RECENT FINDINGS

This review presents updated insights on how to approach irEC, including novel approaches to selective immunosuppressive therapy, the role of fecal microbiota transplant, and the underlying cellular mechanisms of irEC. This review provides an update on irEC diagnosis and therapy, with considerations of new therapies and special patient populations. The field of gastrointestinal irAEs requires additional investigation, which will ultimately provide the tools required for patients to continue to receive life-saving ICI therapy.

Immune Checkpoint Inhibitor-associated Diarrhea and Colitis: A Systematic Review and Meta-analysis of Observational Studies

BACKGROUND

Immune checkpoint inhibitors (ICIs) have transformed the management of advanced malignancies but are associated with diarrhea and colitis. The objective of our systematic review and meta-analysis was to determine the incidence and outcomes of ICI-associated diarrhea and colitis. Bibliographic databases were searched through August 13, 2019, for observational studies of ICI therapy reporting the incidence and/or treatment of diarrhea or colitis. The primary outcome was ICI-associated diarrhea and colitis. Meta-analyses were performed with random-effects models. Twenty-five studies (N=12,661) were included. All studies had a high risk of bias in at least 1 domain. The overall incidence of diarrhea/colitis was 12.8% [95% confidence interval (CI), 8.8-18.2, I2=96.5]. The incidence was lower in patients treated with anti-programmed cell death 1/programmed death-ligand 1 (4.1%, 95% CI, 2.6-6.5) than in those treated with anti-cytotoxic T-cell lymphocyte-associated antigen 4 (20.1%, 95% CI, 15.9-25.1). The remission of diarrhea and/or colitis was higher in patients treated with corticosteroids plus biologics (88.4%, 95% CI, 79.4-93.8) than in those treated with corticosteroids alone (58.3%, 95% CI, 49.3-66.7, Q=18.7, P<0.001). ICI were permanently discontinued in 48.1% of patients (95% CI, 17.8-79.1). ICI were restarted after temporary interruption in 48.6% of patients (95% CI, 18.2-79.4) of whom 17.0% (95% CI, 6.4-30.0) experienced recurrence. Real-world incidence of ICI-associated diarrhea/colitis exceeds 10%. These events lead to permanent ICI discontinuation in just over 50% of patients, while <20% have recurrence of symptoms if ICI are resumed. Further studies are needed to identify patients who would benefit from early treatment with biologics as well as appropriate patients to resume ICI therapy.

Comparative assessment of manual chart review and ICD claims data in evaluating immunotherapy-related adverse events

BACKGROUND

The aim of this retrospective study was to demonstrate that irAEs, specifically gastrointestinal and pulmonary, examined through International Classification of Disease (ICD) data leads to underrepresentation of true irAEs and overrepresentation of false irAEs, thereby concluding that ICD claims data are a poor approach to electronic health record (EHR) data mining for irAEs in immunotherapy clinical research.

METHODS

This retrospective analysis was conducted in 1,063 cancer patients who received ICIs between 2011 and 2017. We identified irAEs by manual review of medical records to determine the incidence of each of our endpoints, namely colitis, hepatitis, pneumonitis, other irAE, or no irAE. We then performed a secondary analysis utilizing ICD claims data alone using a broad range of symptom and disease-specific ICD codes representative of irAEs.

RESULTS

16% (n = 174/1,063) of the total study population was initially found to have either pneumonitis 3% (n = 37), colitis 7% (n = 81) or hepatitis 5% (n = 56) on manual review. Of these patients, 46% (n = 80/174) did not have ICD code evidence in the EHR reflecting their irAE. Of the total patients not found to have any irAEs during manual review, 61% (n = 459/748) of patients had ICD codes suggestive of possible irAE, yet were not identified as having an irAE during manual review.

DISCUSSION

Examining gastrointestinal and pulmonary irAEs through the International Classification of Disease (ICD) data leads to underrepresentation of true irAEs and overrepresentation of false irAEs.

Immune checkpoint inhibitor-mediated colitis in gastrointestinal malignancies and inflammatory bowel disease

Immune checkpoint inhibitors (ICI) have markedly changed the landscape of cancer therapy. By re-invigorating the immune system against tumors, ICI provide novel therapeutic options for a broad variety of malignancies, including many gastrointestinal (GI) cancers. However, these therapies can also induce autoimmune-like side effects in healthy tissue across the body. One of the most common of these side effects is ICI-mediated colitis and diarrhea (IMC). Here, we review the incidence and risk of IMC in ICI therapy, with a focus on what is known regarding IMC in patients with GI malignancies. We also discuss data available on the use of ICI and risk of IMC in patients with pre-existing inflammatory bowel disease, as these patients may have increased risk of IMC due to their underlying intestinal pathology.

Inhibitors of immune checkpoints-PD-1, PD-L1, CTLA-4-new opportunities for cancer patients and a new challenge for internists and general practitioners

The treatment of cancer patients with immune checkpoint inhibitors (ICI) (anti-CTLA-4, anti-PD-1, anti-PD-L1, combined therapy anti-PD-1/PD-L1 with anti-CTLA-4) has without doubt been a significant breakthrough in the field of oncology in recent years and constitutes a major step forward as a novel type of immunotherapy in the treatment of cancer. ICIs have contributed to a significant improvement in the outcome of treatment and prognosis of patients with different types of malignancy. With the expansion of the use of ICIs, it is expected that caregivers will face new challenges, namely, they will have to manage the adverse side effects associated with the use of these drugs. New treatment options pose new challenges not only for oncologists but also for specialists in other clinical fields, including general practitioners (GPs). They also endorse the need for taking a holistic approach to the patient, which is a principle widely recognized in oncology and especially relevant in the case of the expanding use of ICIs, which may give rise to a wide variety of organ complications resulting from treatment. Knowledge and awareness of the spectrum of immune-related adverse events (irAEs) will allow doctors to qualify patients for treatment more appropriately, prevent complications, correctly recognize, and ultimately treat them. Additionally, patients with more non-specific symptoms would be expected, in the first instance, to consult their general practitioners, as complications may appear even after the termination of treatment and do not always proceed in line with disease progression. Dealing with any iatrogenic complications, will not only be the remit of oncologists but because of the likelihood that specific organs may be affected, is likely to extend also to specialists in various fields of internal medicine. These specialists, e.g., endocrinologists, dermatologists, pulmonologists, and gastroenterologists, are likely to receive referrals for patients suffering from specific types of adverse events or will be asked to provide care in cases requiring hospitalization of patients with complications in their field of expertise. In view of these considerations, we believe that there is an urgent need for multidisciplinary teamwork in the treatment of cancer patients undergoing immunotherapy and suffering the consequent adverse reactions to treatment.

Consensus disease definitions for neurologic immune-related adverse events of immune checkpoint inhibitors

Expanding the US Food and Drug Administration-approved indications for immune checkpoint inhibitors in patients with cancer has resulted in therapeutic success and immune-related adverse events (irAEs). Neurologic irAEs (irAE-Ns) have an incidence of 1%-12% and a high fatality rate relative to other irAEs. Lack of standardized disease definitions and accurate phenotyping leads to syndrome misclassification and impedes development of evidence-based treatments and translational research. The objective of this study was to develop consensus guidance for an approach to irAE-Ns including disease definitions and severity grading. A working group of four neurologists drafted irAE-N consensus guidance and definitions, which were reviewed by the multidisciplinary Neuro irAE Disease Definition Panel including oncologists and irAE experts. A modified Delphi consensus process was used, with two rounds of anonymous ratings by panelists and two meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness and accuracy on 9-point scales in electronic surveys and provided free text comments. Aggregated survey responses were incorporated into revised definitions. Consensus was based on numeric ratings using the RAND/University of California Los Angeles (UCLA) Appropriateness Method with prespecified definitions. 27 panelists from 15 academic medical centers voted on a total of 53 rating scales (6 general guidance, 24 central and 18 peripheral nervous system disease definition components, 3 severity criteria and 2 clinical trial adjudication statements); of these, 77% (41/53) received first round consensus. After revisions, all items received second round consensus. Consensus definitions were achieved for seven core disorders: irMeningitis, irEncephalitis, irDemyelinating disease, irVasculitis, irNeuropathy, irNeuromuscular junction disorders and irMyopathy. For each disorder, six descriptors of diagnostic components are used: disease subtype, diagnostic certainty, severity, autoantibody association, exacerbation of pre-existing disease or de novo presentation, and presence or absence of concurrent irAE(s). These disease definitions standardize irAE-N classification. Diagnostic certainty is not always directly linked to certainty to treat as an irAE-N (ie, one might treat events in the probable or possible category). Given consensus on accuracy and usability from a representative panel group, we anticipate that the definitions will be used broadly across clinical and research settings.

The dark side of immunotherapy

Immunotherapy has broadened the therapeutic scope and response for many cancer patients with drugs that are generally of higher efficacy and less toxicity than prior therapies. Multiple classes of immunotherapies such as targeted antibodies and immune checkpoint inhibitors (ICI), cell-based immunotherapies, immunomodulators, vaccines, and oncolytic viruses have been developed to help the immune system target and destroy malignant tumors. ICI targeting programmed cell death protein-1 (PD-1) or its ligand (PD-L1) are among the most effective immunotherapy agents and are a major focus of current investigations. They have received approval for at least 16 different tumor types as well as for unresectable or metastatic tumors with microsatellite instability-high (MSI-H) or mismatch repair deficiency or with high tumor mutational burden (defined as ≥10 mutations/megabase). However, it is important to recognize that immunotherapy may be associated with significant adverse events. To summarize these events, we conducted a PubMed and Google Scholar database search through April 2020 for manuscripts evaluating treatment-related adverse events and knowledge gaps associated with the use of immunotherapy. Reviewed topics include immune-related adverse events (irAEs), toxicities on combining immunotherapy with other agents, disease reactivation such as tuberculosis (TB) and sarcoid-like granulomatosis, tumor hyperprogression (HPD), financial toxicity, challenges in special patient populations such as solid organ transplant recipients and those with auto-immune diseases. We also reviewed reports of worse or even lethal outcomes compared to other oncologic therapies in certain scenarios and summarized biomarkers predicting adverse events.

Organ-Specific Immune-Related Adverse Events for PD-1 Antibodies in Lung Cancer Treatment

Anti-PD-1 therapy has revolutionized the clinical treatment of lung cancer. With the increasing number of lung cancer patients being treated, there is also an increase in the number of immune-related adverse events (irAEs) being reported. These irAEs involve multiple organs and systems, mainly manifest as inflammatory side effects, and are different from the adverse events observed with traditional lung cancer treatment. These effects are often mild and treatable and reversible; however, in a few cases the side effects can be severe and lead to termination of immunotherapy. Management involves glucocorticoid-based related immunomodulators, which should be carefully prescribed to balance the efficacy and side effects of the PD-1 antibody treatment. This review will describe the characteristics and mechanisms of irAEs in specific organs, and will serve as a guide to help optimize treatment plans and improve patient outcomes.

Systematic review with meta-analysis: effectiveness of anti-inflammatory therapy in immune checkpoint inhibitor-induced enterocolitis

BACKGROUND

Immune checkpoint inhibitors have revolutionised cancer treatment, but at the cost of off-target immune-mediated organ damage. This includes checkpoint inhibitor-induced enterocolitis which frequently requires hospitalisation and may be life-threatening. Empiric treatment typically includes corticosteroids and infliximab, although no large-scale studies have confirmed their effectiveness.

AIM

To investigate the effectiveness of anti-inflammatory therapy in checkpoint inhibitor-induced enterocolitis METHODS: We performed a systematic review and meta-analysis of studies reporting clinical outcomes of checkpoint inhibitor-induced enterocolitis in adult cancer patients treated with anti-inflammatory agents. We searched Medline, EMBASE, and the Cochrane library through April and extracted the proportion of patients responding to anti-inflammatory therapy. Variation in effect size was studied using a random-effects meta-regression analysis, with checkpoint inhibitor agent and tumour type as the variables.

RESULTS

Data were pooled from 1210 treated patients across 39 studies. Corticosteroids were effective in 59% (95% CI 54- 65) of patients, with response significantly more favourable in patients treated with anti-PD-1/L1 monotherapy, compared with anti-CTLA-4 containing regimens (78%, 95% CI 69-85 vs 56 %, 95% CI 49-63, P = 0.003), and more favourable in lung cancer patients compared with melanoma patients (88%, 95% CI 62-97 vs 55%, 95% CI 47-63, P = 0.04). Infliximab was effective in 81% (95% CI 73-87) of patients, and vedolizumab in 85% (95% CI 60-96).

CONCLUSION

Corticosteroids, infliximab and vedolizumab, are effective in the treatment of checkpoint inhibitor-induced enterocolitis. Checkpoint inhibitor regimen and cancer type were significant moderators in response to corticosteroid therapy.

Immunotherapy induced enterocolitis and gastritis - What to do and when?

Oncological treatment has been revolutionised by the advent of immune checkpoint inhibitors (ICPi), which block inhibitory immune pathways to enhance anti-tumour responses and improve survival. This mode of action is non-specific so can cause immune-related adverse events, of which diarrhoea and enterocolitis are amongst the most common. ICPi-enterocolitis frequently leads to cancer therapy interruption. ICPi-gastritis typically occurs at a later stage of ICPi therapy and can present more insidiously with nausea and vomiting. ICPi-enterocolitis and gastritis are treated with corticosteroids, with refractory cases typically requiring biologic therapy. This review will briefly consider the pathogenesis of ICPi-induced GI disease, before focussing on the practical management of these conditions. The anticipated global increase in ICPi use across cancer types highlights the importance of prospective research in order that we can understand the immuno-microbiology of ICPi-enterocolitis and gastritis. This will lead to predictive biomarkers and help to define optimal treatment regimens.

What have we learned from animal models of idiosyncratic, drug-induced liver injury?

INTRODUCTION

Idiosyncratic, drug-induced liver injury (IDILI) continues to plague patients and restrict the use of drugs that are pharmacologically effective. Mechanisms of IDILI are incompletely understood, and a better understanding would reduce speculation and could help to identify safer drug candidates preclinically. Animal models have the potential to enhance knowledge of mechanisms of IDILI.

AREAS COVERED

Numerous hypotheses have emerged to explain IDILI pathogenesis, many of which center on the roles of the innate and/or adaptive immune systems. Animal models based on these hypotheses are reviewed in the context of their contributions to understanding of IDILI and their limitations.

EXPERT OPINION

Animal models of IDILI based on an activated adaptive immune system have to date failed to reproduce major liver injury that is of most concern clinically. The only models that have so far resulted in pronounced liver injury are based on the multiple determinant hypothesis or the inflammatory stress hypothesis. The liver pathogenesis in IDILI animal models involves various leukocytes and immune mediators such as cytokines. Insights from animal models are changing the way we view IDILI pathogenesis and are leading to better approaches to preclinical prediction of IDILI potential of new drug candidates.

Retrospective Analysis of Treatment and Complications of Immune Checkpoint Inhibitor-Associated Colitis: Histological Ulcerations as Potential Predictor for a Steroid-Refractory Disease Course

Background/Aims

Among the severe immune-related adverse events (irAEs) that occur with immune checkpoint inhibitor (ICI) therapy, colitis is the most frequent one. This study aimed at describing the experience from the largest gastroenterology unit in Switzerland with immune checkpoint inhibitor-associated colitis (ICIAC), its clinical presentation, management, and outcomes.

Methods

We performed a retrospective review of patients who were referred for the evaluation of ICIAC between January 2011 and October 2018 to the Division of Gastroenterology and Hepatology, University Hospital Zurich.

Results

Thirty-three patients with immune-related colitis grade 3 or 4 met the inclusion criteria and were analyzed in detail: All patients had diarrhea, 64% had abdominal pain, 42% had bloody stool, 27% had emesis, and 18% developed fever. In total, 33% were successfully treated with corticosteroids alone; 66% were steroid-refractory and treated with infliximab or vedolizumab. Two of these patients developed severe complications requiring surgery. All patients reached complete remission of ICIAC and its symptoms. At colonoscopy, ulcerations were seen in 37% of steroid-refractory versus 63% of steroid-responsive cases. Deep histological ulcerations invading the submucosa were only present in steroid-refractory cases.

Conclusion

ICIAC is a severe irAE which frequently requires high-dose steroids and a close follow-up due to deleterious complications. The detection of histologically diagnosed deep ulcerations may predict a steroid-refractory course and may warrant early application of infliximab. However, larger studies are required to confirm our findings.

Mucosal inflammation predicts response to systemic steroids in immune checkpoint inhibitor colitis

BACKGROUND

Immune-related colitis is a common, often serious complication of immune checkpoint inhibition (ICI). Although endoscopy is not strictly recommended for any grade of diarrhea/colitis, emerging evidence suggests that endoscopic evaluation may have important therapeutic implications. In this retrospective study, we sought to comprehensively characterize the clinical and histologic features of ICI-induced colitis with a specific focus on evaluating the prognostic role of endoscopy.

METHODS

Data were collected from the medical records of 130 patients with confirmed ICI-induced colitis. In a subset of patients (n=44) with endoscopic and pathologic data, endoscopic data were scored using the Mayo Endoscopic Score (MES) with scores ranging from 0 (no inflammation) to 3 (colonic ulceration). The impact of infliximab on antitumor outcomes was evaluated using progression-free survival (PFS) and overall survival (OS).

RESULTS

We identified 130 patients with ICI-induced colitis across two institutions. All patients were treated with corticosteroids. Additional and/or alternative immunosuppression was employed in 59 cases, with 52 patients (42%) requiring at least one infusion of infliximab 5 mg/kg. Endoscopic assessment with biopsy was performed in 123 cases of suspected colitis (95%), with 44 cases available for MES tabulation. Presence of ulceration (MES 3) was associated with use of infliximab (p=0.008) and MES was significantly higher in patients who received infliximab compared with those who did not (p=0.003) with a median score of 2.5; conversely, those with an MES of zero rarely required secondary immunosuppression. Notably, symptoms of colitis based on Common Terminology Criteria for Adverse Events grade had no association with endoscopic findings based on MES classification. After adjustment for baseline patient and disease characteristics, there was no significant difference in steroid duration or cancer-related outcomes in patients treated with infliximab.

CONCLUSIONS

In our study, we demonstrate the association of endoscopic features, specifically the MES, with immunosuppressive needs. Importantly, we also show that MES was not related to severity of patient symptoms. The data suggest that endoscopic features can guide clinical decision-making better than patient symptoms, both identifying high-risk patients who will require infliximab and those who are likely to respond to initial corticosteroids.

Immune-related adverse events of checkpoint inhibitors

Cancer immunotherapies have changed the landscape of cancer treatment during the past few decades. Among them, immune checkpoint inhibitors, which target PD-1, PD-L1 and CTLA-4, are increasingly used for certain cancers; however, this increased use has resulted in increased reports of immune-related adverse events (irAEs). These irAEs are unique and are different to those of traditional cancer therapies, and typically have a delayed onset and prolonged duration. IrAEs can involve any organ or system. These effects are frequently low grade and are treatable and reversible; however, some adverse effects can be severe and lead to permanent disorders. Management is primarily based on corticosteroids and other immunomodulatory agents, which should be prescribed carefully to reduce the potential of short-term and long-term complications. Thoughtful management of irAEs is important in optimizing quality of life and long-term outcomes.

Immune-Related Adverse Events (irAEs): Diagnosis, Management, and Clinical Pearls

PURPOSE OF REVIEW

While immune checkpoint inhibitor (ICI) therapy has improved melanoma patient outcomes, it has also resulted in the rise of unique immune-related adverse events (irAEs). Here, we review and synthesize irAE management recommendations from several oncological societies into a streamlined format to aid in diagnosis and management. We also include clinical pearls highlighting several recent research studies in this field.

RECENT FINDINGS

Knowledge of immunotherapy toxicity has continually evolved, and several major oncologic societies have recently released new or updated guidelines. Keeping up with the evolving field of immunotherapy and related toxicities is crucial, because ICI use, in combination with other agents, will only continue to increase and likely result in new and different patterns of irAEs. Providing clear and concise references for clinicians will help ensure proper irAE evaluation and management going forward. We present one such reference here, covering management of common and/or serious irAEs.

Autoimmune diseases and immune-checkpoint inhibitors for cancer therapy: review of the literature and personalized risk-based prevention strategy

Patients with cancer and with preexisting active autoimmune diseases (ADs) have been excluded from immunotherapy clinical trials because of concerns for high susceptibility to the development of severe adverse events resulting from exacerbation of their preexisting ADs. However, a growing body of evidence indicates that immune-checkpoint inhibitors (ICIs) may be safe and effective in this patient population. However, baseline corticosteroids and other nonselective immunosuppressants appear to negatively impact drug efficacy, whereas retrospective and case report data suggest that use of specific immunosuppressants may not have the same consequences. Therefore, we propose here a two-step strategy. First, to lower the risk of compromising ICI efficacy before their initiation, nonselective immunosuppressants could be replaced by specific selective immunosuppressant drugs following a short rotation phase. Subsequently, combining ICI with the selective immunosuppressant could prevent exacerbation of the AD. For the most common active ADs encountered in the context of cancer, we propose specific algorithms to optimize ICI therapy. These preventive strategies go beyond current practices and recommendations, and should be practiced in ICI-specialized clinics, as these require multidisciplinary teams with extensive knowledge in the field of clinical immunology and oncology. In addition, we challenge the exclusion from ICI therapy for patients with cancer and active ADs and propose the implementation of an international registry to study such novel strategies in a prospective fashion.

Gastrointestinal and Hepatic Complications of Immunotherapy: Current Management and Future Perspectives

PURPOSE OF REVIEW

Checkpoint inhibitor (CPI) immunotherapy has transformed the treatment of multiple cancers over the past decade, leading to durable remissions, but also to severe inflammatory toxicities. These toxicities, termed immune-related adverse events (irAEs), can affect any organ system in the body, but commonly induce inflammation in barrier organs. Gastrointestinal (GI) and hepatic irAEs are among the most frequent and most severe from contemporary immunotherapies, with inflammation in the colon and or small intestines (entero)colitis as the single most common GI irAE. The aim of this review is to describe the evidence supporting our current understanding of CPI enterocolitis and hepatitis, as well as the management of these entities.

RECENT FINDINGS

Although most patients who develop enterocolitis recover without long-term GI sequelae, enterocolitis is still an important reason for treatment discontinuation, which, in patients with metastatic cancer, can be a life-threatening outcome. At present, we have almost no prospective, randomized data regarding the management of CPI enterocolitis, and current management algorithms are based on expert opinion and small retrospective studies with a high likelihood of bias. Retrospective studies have defined colonic ulceration as a predictor of colitis responsiveness to corticosteroids, and have defined microscopic colitis as a subtype of CPI enterocolitis with a distinct treatment response. Corticosteroids appear to be effective for 60-70% of patients with CPI enterocolitis, with about a third of patients requiring escalation to a biologic agent such as infliximab or vedolizumab. Yet proper sequencing of these treatments to minimize risk and maximize treatment benefit has not been established, and we do not know how treatment of colitis influences cancer outcomes. CPI enterocolitis and hepatitis are important causes of treatment interruption and discontinue, and significant morbidity in patients undergoing immunotherapy. As guidelines for diagnosis and management rely heavily on expert opinion, we have an urgent need for randomized and prospective trials that use both colitis and cancer outcomes to determine optimal management strategies.

Budesonide treatment for microscopic colitis from immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (CPIs) are effective against a variety of malignancies but can be limited by inflammatory toxicities such as enterocolitis. Enterocolitis is typically treated with systemically active glucocorticoids. Endoscopy can stratify patients by the severity of mucosal inflammation, including identifying patients with colitis in the absence of visible mucosal changes: microscopic colitis. Whether patients with CPI microscopic colitis could be managed differently from colitis with more severe mucosal involvement is unclear. The objective of this study was to describe outcomes in CPI microscopic colitis focusing on the response to first line treatment with budesonide.

METHODS

We evaluated data from a retrospective cohort from a single-center large academic hospital. The participants were all adult patients evaluated by endoscopy for suspected CPI enterocolitis between 3/2017 and 3/2019. The exposures were: Mayo Endoscopic Score (range 0-3). The subset was: oral budesonide, maximum dose 12 mg daily, administered minimum of 5 weeks. The main outcomes and measures were: Primary: time from first CPI exposure to first glucocorticoid use; use of systemic glucocorticoids; time from symptom onset to resolution; continuation of CPI therapy; number of additional CPI infusions received. Secondary: admissions for symptom control; novel irAE development; need for second-line immunosuppression; oncologic outcomes.

RESULTS

We identified 38 patients with biopsy confirmed CPI enterocolitis, 13 in the microscopic colitis cohort, and 25 in the non-microscopic colitis cohort. Budesonide use was higher in the microscopic colitis cohort (12/13 vs 3/25, p < 0.001), and systemic glucocorticoid use was higher in non-microscopic colitis (22/25 vs. 3/13, p < 0.001). Time from symptom onset to resolution did not differ. Microscopic colitis patients more frequently remained on CPI after developing (entero)colitis (76.9% vs 16.0%, p < 0.001). Microscopic colitis patients tolerating further CPI received, on average, 4.2 CPI infusions more than non-microscopic colitis patients tolerating CPI (5.8 vs 1.6, p = 0.03). Microscopic colitis was associated with increased time-to-treatment-failure (HR 0.30, 95% CI 0.14-0.66) and progression-free survival (HR 0.22, 95% CI 0.07-0.70).

CONCLUSIONS

Gastrointestinal mucosal inflammation without visible mucosal injury is a distinct, prevalent CPI enterocolitis subset that can be diagnosed by endoscopy. First-line budesonide appears effective in controlling "microscopic colitis" symptoms and prolonging immunotherapy duration. These findings present a compelling rationale for routine endoscopic evaluation of suspected CPI enterocolitis and suggest an alternative glucocorticoid-sparing treatment strategy for a subset of such patients.

Colitis after checkpoint blockade: A retrospective cohort study of melanoma patients requiring admission for symptom control

BACKGROUND

Immune checkpoint inhibitors (CPIs) have revolutionized oncologic therapy but can lead to immune-related adverse events (irAEs). Corticosteroids are first-line treatment with escalation to biologic immunosuppression in refractory cases. CPI-related gastroenterocolitis (GEC) affects 20%-50% of patients receiving CPIs and can carry significant morbidity and mortality. Severe CPI-related GEC is not well-described. We present the clinical characterization of all CPI-related GEC requiring admission at a single institution.

METHODS

Clinical, laboratory, radiographic, and endoscopic data were extracted from charts of all melanoma patients ≥18 years of age admitted to one institution for CPI-related GEC, from February 5, 2011 to December 13, 2016. Patients were followed until December 31, 2017 for further admissions. Survival, outcomes, and pharmaceutical-use analyses were performed.

RESULTS

Median time-to-admission from initial CPI exposure was 73.5 days. Median length of stay was 4.5 days. About 50.0% required second-line immunosuppression. Readmission for recrudescence occurred in 33.3%. Common Terminology Criteria for Adverse Events (CTCAE) grade was not significantly associated with outcomes. Hypoalbuminemia (P = 0.005), relative lymphopenia (P = 0.027), and decreased lactate dehydrogenase (P = 0.026) were associated with second-line immunosuppression. There was no difference in progression-free survival (PFS) or OS (P = 0.367, 0.400) for second-line immunosuppression. Subgroup analysis showed that early corticosteroid administration (P = 0.045) was associated with decreased PFS.

CONCLUSIONS

Severe CPI-related GEC typically manifests within 3 months of immunotherapy exposure. Rates of second-line immunosuppression and readmission for recrudescence were high. CTCAE grade did not capture the degree of severity in our cohort. Second-line immunosuppression was not associated with poorer oncologic outcomes; however, early corticosteroid exposure was associated with decreased PFS. Further investigation is warranted.

Concurrent therapy with immune checkpoint inhibitors and TNFα blockade in patients with gastrointestinal immune-related adverse events

BACKGROUND

Immune checkpoint inhibitors (ICI) have demonstrated remarkable efficacy as cancer therapeutics, however, their use remains limited due to the development of immune related adverse events (irAEs). Immune related enterocolitis (irEC) is among the most common severe irAEs leading to the discontinuation of ICIs. Inhibitors of tumor necrosis factor alpha (anti-TNFα) have been used to treat irEC. Recent animal studies have shown that concurrent treatment with anti-TNFα and ICIs improves tumor responses and decreases colitis severity. This approach has not yet been studied in prospective trials in humans. Here we describe, for the first time, the outcomes of patients who were treated concurrently with anti-TNFα and one or two ICIs.

CASE PRESENTATIONS

Five patients with different primary malignancies were treated with ipilimumab/nivolumab (2 patients), pembrolizumab (1 patient), ipilimumab (1 patient), or cemiplimab (1 patient). All patients developed irEC within 40 days of their first ICI dose. The patients presented with a combination of upper and lower gastrointestinal symptoms and subsequently underwent upper endoscopy and/or lower endoscopy. Endoscopy results demonstrated a spectrum of acute inflammatory changes across the gastrointestinal tract. Steroid therapy was used as first line treatment. To prevent prolonged steroid use and recurrence of gastrointestinal inflammation after resumption of cancer therapy, patients were treated concurrently with infliximab and ICI. Patients tolerated further ICI therapy with no recurrence of symptoms. Repeat endoscopies showed resolution of acute inflammation and restaging imaging showed no cancer progression.

CONCLUSIONS

Concurrent treatment with anti-TNFα and ICI appears to be safe, facilitates steroid tapering, and prevents irEC. Prospective clinical trials are needed to assess the outcomes of this treatment modality.