Systematic review: colitis associated with anti-CTLA-4 therapy

Checkpoints and beyond - Immunotherapy in colorectal cancer

Immunotherapy is the latest revolution in cancer therapy. It continues to show impressive results in malignancies like melanoma and others. At least so far, effects are modest in colorectal cancer (CRC) and only a subset of patients benefits from already approved checkpoint inhibitors. In this review, we discuss major hurdles of immunotherapy like the immunosuppressive niche and low immunogenicity of CRC next to current achievements of checkpoint inhibitors, interleukin treatment and adoptive cell transfer (dendritic cells/cytokine induced killer cells, tumor infiltrating lymphocytes, chimeric antigen receptor cells, T cell receptor transfer) in pre-clinical models and clinical trials. We intensively examine approaches to overcome low immunogenicity by combination of different therapies and address future strategies of therapy as well as the need of predictive factors in this emerging field of precision medicine.

Immune checkpoint inhibitor-induced gastrointestinal and hepatic injury: pathologists' perspective

Immune checkpoint inhibitors (CPIs) are a relatively new class of 'miracle' dugs that have revolutionised the treatment and prognosis of some advanced-stage malignancies, and have increased the survival rates significantly. This class of drugs includes cytotoxic T lymphocyte antigen-4 inhibitors such as ipilimumab; programmed cell death protein-1 inhibitors such as nivolumab, pembrolizumab and avelumab; and programmed cell death protein ligand-1 inhibitors such as atezolizumab. These drugs stimulate the immune system by blocking the coinhibitory receptors on the T cells and lead to antitumoural response. However, a flip side of these novel drugs is immune-related adverse events (irAEs), secondary to immune-mediated process due to disrupted self-tolerance. The irAEs in the gastrointestinal (GI) tract/liver may result in diarrhoea, colitis or hepatitis. An accurate diagnosis of CPI-induced colitis and/or hepatitis is essential for optimal patient management. As we anticipate greater use of these drugs in the future given the significant clinical response, pathologists need to be aware of the spectrum of histological findings that may be encountered in GI and/or liver biopsies received from these patients, as well as differentiate them from its histopathological mimics. This present review discusses the clinical features, detailed histopathological features, management and the differential diagnosis of the luminal GI and hepatic irAEs that may be encountered secondary to CPI therapy.

Resolution of Infliximab-Refractory Nivolumab-Induced Acute Severe Enterocolitis After Cyclosporine Treatment in a Patient with Non-Small Cell Lung Cancer

BACKGROUND Enterocolitis is an immune-related adverse event associated with nivolumab treatment. Although intravenous corticosteroids and infliximab are recommended as a first-line and second-line therapy, respectively, there is no established treatment for severe enterocolitis that is refractory to these drugs. CASE REPORT A 62-year-old male with non-small cell lung cancer, with multiple brain metastasis, received nivolumab as the eighth-line chemotherapy for his disease. A few days after nivolumab administration, grade 2-3 enterocolitis developed in the patient. The enterocolitis improved to grade 1 after careful observation; however, it was aggravated to grade 3 after resuming nivolumab treatment. After cessation of nivolumab, 3.3 mg of intravenous dexamethasone and 40 mg of methylprednisolone were administered for 16 days and subsequently 30-60 mg of oral prednisolone was administered for 50 days, with little improvement in the patient's colitis. A second-line treatment with 5 mg/kg of infliximab was twice attempted, but the patient had persistent diarrhea. Therefore, 50 mg of oral cyclosporine was started as a third-line therapy. Three days after the start of cyclosporine, the number of diarrhea events decreased, with resolution 2 weeks after cyclosporine administration. CONCLUSIONS Oral cyclosporine treatment can be a third-line therapy for enterocolitis associated with immune-related adverse events.

Management of side effects of immune checkpoint blockade by anti-CTLA-4 and anti-PD-1 antibodies in metastatic melanoma

CTLA-4 and PD-1 are potential targets for tumor-induced downregulation of lymphocytic immune responses. Immune checkpoint-modifying monoclonal antibodies oppose these effects, inducing T cell-mediated immune responses to various tumors including melanoma. Both anti-CTLA-4 and anti-PD-1 antibodies modify the interaction between tumor, antigen-presenting cells, and T lymphocytes. With respect to overall survival, clinical studies have shown a major benefit for the anti-CTLA-4 antibody ipilimumab as well as the two anti-PD-1 antibodies nivolumab and pembrolizumab. Following approval of ipilimumab in 2011, the latter two achieved market authorization in the summer of 2015. Immune responses thus induced and enhanced inevitably entail autoimmune phenomena, affecting various organs to varying degrees. Knowledge of these side effects is crucial with regard to prevention and management by treating physicians. Typically occurring early on and presenting with pronounced and persistent diarrhea, colitis represents a major and severe side effect. Other immune-mediated disorders include dermatitis, hypophysitis, thyroiditis, hepatitis, iridocyclitis as well as other less common autoimmune phenomena. Early recognition and initiation of treatment can reduce risks and sequelae for patients. This review describes the mechanisms of action of immune checkpoint blockade as well as its clinical effects in metastatic melanoma, with a detailed focus on the spectrum of adverse events and their therapeutic management.

Next generation of immune checkpoint therapy in cancer: new developments and challenges

Immune checkpoints consist of inhibitory and stimulatory pathways that maintain self-tolerance and assist with immune response. In cancer, immune checkpoint pathways are often activated to inhibit the nascent anti-tumor immune response. Immune checkpoint therapies act by blocking or stimulating these pathways and enhance the body's immunological activity against tumors. Cytotoxic T lymphocyte-associated molecule-4 (CTLA-4), programmed cell death receptor-1 (PD-1), and programmed cell death ligand-1(PD-L1) are the most widely studied and recognized inhibitory checkpoint pathways. Drugs blocking these pathways are currently utilized for a wide variety of malignancies and have demonstrated durable clinical activities in a subset of cancer patients. This approach is rapidly extending beyond CTLA-4 and PD-1/PD-L1. New inhibitory pathways are under investigation, and drugs blocking LAG-3, TIM-3, TIGIT, VISTA, or B7/H3 are being investigated. Furthermore, agonists of stimulatory checkpoint pathways such as OX40, ICOS, GITR, 4-1BB, CD40, or molecules targeting tumor microenvironment components like IDO or TLR are under investigation. In this article, we have provided a comprehensive review of immune checkpoint pathways involved in cancer immunotherapy, and discuss their mechanisms and the therapeutic interventions currently under investigation in phase I/II clinical trials. We also reviewed the limitations, toxicities, and challenges and outline the possible future research directions.

Immune Checkpoint Inhibitor-Induced Colitis: Diagnosis and Management

Immune checkpoint inhibitors are monoclonal antibodies indicated for an increasing number of malignant diseases. These agents can cause specific side effects, which need to be anticipated while clear patterns of management need to be established. Immune checkpoint inhibitor-mediated gastrointestinal side effects, including diarrhea and colitis, occur in up to 30% of patients. Severe colitis can lead to severe dehydration or intestinal perforation. Endoscopic lesions and histopathological features of immune checkpoint inhibitor-induced colitis are similar to an inflammatory bowel disease (IBD) flare. Patients with immune checkpoint inhibitor-induced diarrhea and colitis are treated with corticosteroids. Infliximab can be used in cases of corticosteroid failure. Rectosigmoïdoscopy or colonoscopy should be performed when severe immune checkpoint inhibitor-induced colitis is suspected, but endoscopic investigations should not delay treatment. Specific patient education as well as co-operation between oncologists and gastroenterologists is essential.

Identifying and managing the adverse effects of immune checkpoint blockade

Immunotherapy has revolutionized the field of oncology. By inhibiting the cytotoxic T-lymphocyte-associated protein (CTLA-4) and programmed death-1 (PD-1) immune checkpoint pathways, multiple studies have demonstrated greatly improved survival in locally advanced and metastatic cancers including melanoma, renal, lung, gastric, and hepatocellular carcinoma. Trials in other malignancies are ongoing, and undoubtedly the number of drugs in this space will grow beyond the six currently approved by the Food and Drug Administration. However, by altering the immune response to fight cancer, a new class of side effects has emerged known as immune-related adverse events (irAEs). These adverse events are due to overactivation of the immune system in almost any organ of the body, and can occur at any point along a patient's treatment course. irAEs such as endocrinopathies (thyroiditis), colitis, and pneumonitis may occur more commonly. However, other organs such as the liver, heart, or brain may also be affected by immune overactivation and any of these side effects may become life threatening. This review presents an approach to promptly recognize and manage these toxicities, to hopefully minimize morbidity and mortality from irAEs.

Baseline gut microbiota predicts clinical response and colitis in metastatic melanoma patients treated with ipilimumab

Background

Ipilimumab, an immune checkpoint inhibitor targeting CTLA-4, prolongs survival in a subset of patients with metastatic melanoma (MM) but can induce immune-related adverse events, including enterocolitis. We hypothesized that baseline gut microbiota could predict ipilimumab anti-tumor response and/or intestinal toxicity.

Patients and methods

Twenty-six patients with MM treated with ipilimumab were prospectively enrolled. Fecal microbiota composition was assessed using 16S rRNA gene sequencing at baseline and before each ipilimumab infusion. Patients were further clustered based on microbiota patterns. Peripheral blood lymphocytes immunophenotypes were studied in parallel.

Results

A distinct baseline gut microbiota composition was associated with both clinical response and colitis. Compared with patients whose baseline microbiota was driven by Bacteroides (cluster B, n = 10), patients whose baseline microbiota was enriched with Faecalibacterium genus and other Firmicutes (cluster A, n = 12) had longer progression-free survival (P = 0.0039) and overall survival (P = 0.051). Most of the baseline colitis-associated phylotypes were related to Firmicutes (e.g. relatives of Faecalibacterium prausnitzii and Gemmiger formicilis), whereas no colitis-related phylotypes were assigned to Bacteroidetes. A low proportion of peripheral blood regulatory T cells was associated with cluster A, long-term clinical benefit and colitis. Ipilimumab led to a higher inducible T-cell COStimulator induction on CD4+ T cells and to a higher increase in serum CD25 in patients who belonged to Faecalibacterium-driven cluster A.

Conclusion

Baseline gut microbiota enriched with Faecalibacterium and other Firmicutes is associated with beneficial clinical response to ipilimumab and more frequent occurrence of ipilimumab-induced colitis.

Managing toxicities associated with immune checkpoint inhibitors: consensus recommendations from the Society for Immunotherapy of Cancer (SITC) Toxicity Management Working Group

Cancer immunotherapy has transformed the treatment of cancer. However, increasing use of immune-based therapies, including the widely used class of agents known as immune checkpoint inhibitors, has exposed a discrete group of immune-related adverse events (irAEs). Many of these are driven by the same immunologic mechanisms responsible for the drugs' therapeutic effects, namely blockade of inhibitory mechanisms that suppress the immune system and protect body tissues from an unconstrained acute or chronic immune response. Skin, gut, endocrine, lung and musculoskeletal irAEs are relatively common, whereas cardiovascular, hematologic, renal, neurologic and ophthalmologic irAEs occur much less frequently. The majority of irAEs are mild to moderate in severity; however, serious and occasionally life-threatening irAEs are reported in the literature, and treatment-related deaths occur in up to 2% of patients, varying by ICI. Immunotherapy-related irAEs typically have a delayed onset and prolonged duration compared to adverse events from chemotherapy, and effective management depends on early recognition and prompt intervention with immune suppression and/or immunomodulatory strategies. There is an urgent need for multidisciplinary guidance reflecting broad-based perspectives on how to recognize, report and manage organ-specific toxicities until evidence-based data are available to inform clinical decision-making. The Society for Immunotherapy of Cancer (SITC) established a multidisciplinary Toxicity Management Working Group, which met for a full-day workshop to develop recommendations to standardize management of irAEs. Here we present their consensus recommendations on managing toxicities associated with immune checkpoint inhibitor therapy.

Immune checkpoint inhibitor colitis: the flip side of the wonder drugs

Immune checkpoint inhibitors block the co-inhibitory receptors on T cells to activate their cytotoxic immune function and are rapidly being explored for the treatment of various advanced-stage malignancies. These novel drugs have already significantly increased survival rates. The first available immune checkpoint inhibitors were cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors (such as ipilimumab), followed by programmed cell death protein 1 (PD-1) and programmed cell death protein ligand 1 (PD-L1) inhibitors (such as pembrolizumab and nivolumab). Anti-PD-1 and anti-PD-L1 therapies have demonstrated better efficacy and tolerability and less severe adverse effects compared to anti-CTLA-4 agents. Idelalisib, a PI3Kδ isoform inhibitor, is another immunotherapeutic agent that is often classified separately and is currently used in treatment of chronic lymphocytic leukemia and non-Hodgkin lymphomas. Despite successful therapeutic responses, immune-related adverse events have been reported with the use of these agents. The gastrointestinal side effects, particularly diarrhea, are among the most commonly reported symptoms. The histologic features of immune checkpoint inhibitor-associated colitis show a spectrum of patterns of injury among various drug classes. There is significant overlap between immune checkpoint inhibitor-associated colitis and other colitides, making the differential diagnosis difficult-especially in the absence of clinical history. The histopathology data on immune checkpoint inhibitor-associated colitis are limited. Here we review clinical features as well as various histologic patterns of colitis associated with these groups of medications.

Inflammatory gastrointestinal diseases associated with PD-1 blockade antibodies

BACKGROUND

Immune check-point blockade agents have shown clinical activity in cancer patients but are associated with immune-related adverse events that could limit their development. The aim of this study was to describe the gastrointestinal immune-related adverse events (GI-irAE) in patients with cancer treated with anti-PD-1.

METHODS

this is a retrospective study of consecutive adult patients who had a suspected GI-irAE due to anti-PD-1 antibodies between 2013 and 2016. Patients were recruited through a pharmacovigilance registry. Patients' data were reviewed by a multidisciplinary committee that included gastroenterologists, oncologists and a pathologist. Quantitative variables are described by median (range), qualitative variable by frequency (percentage).

RESULTS

Forty-four patients were addressed to a Gastroenterology unit for a suspected GI-IrAE. Twenty patients had a confirmed GI-irAE related to anti-PD-1, which occurred 4.2 months (0.2; 22.1) after the initiation of anti-PD-1. GI-IrAE incidence rate under anti-PD-1 treatment was estimated to be 1.5%. Among patients with GI-IrAE, main symptoms were diarrhoea (n = 16, 80%), abdominal pain (n = 13, 65%), nausea and vomiting (n = 11, 55%), intestinal obstruction (n = 1, 5%), and haematochezia (n = 2, 10%). No patient had colectomy. Four distinct categories of GI-irAE were observed: acute colitis (n = 8, 40%), microscopic colitis (n = 7, 35%), upper gastrointestinal tract inflammation (n = 4, 20%) and pseudo-obstruction (n = 1, 5%). Response rates to corticosteroids were 87.5% (7/8) in acute colitis, 57% (4/7) in microscopic colitis and 75% (3/4) in upper gastrointestinal tract inflammation. Median time to resolution was 36 days (6-172) in acute colitis, and 98 days (42-226) in microscopic colitis.

CONCLUSION

This study suggests that GI-irAE are different and less frequent with anti PD-1 than with anti CTLA-4.

Checkpoint inhibitors and gastrointestinal immune-related adverse events

PURPOSE OF REVIEW

Recent development of checkpoint inhibitors is a challenge for oncologists. Indeed, it leads to specific immune adverse events, close to autoimmune disorders, which require a specific management. Colitis is one of the most frequent immune adverse events, in particular with anticytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) therapy.

RECENT FINDINGS

Severe colitis is frequent with immune checkpoint inhibitors and leads in a few cases to bowel perforation and death. This review focuses on specific pathogenic pathway and recent findings on risk factors and managements of colitis.

SUMMARY

Anti-CTLA-4 antibodies are the most involved immune checkpoint inhibitors in colitis, and the combinations with anti-programmed death ligand 1 dramatically increase the rate of colitis. The early use of budesonide, and in some cases corticosteroids and/or infliximab should be recommended, as colitis is responsive to infliximab in almost all cases. Immune-related colitis shares some characteristics with inflammatory bowel disease but with little specificity. In particular, it has been recently showed that gut microbiota could interact with anti-CTLA-4 treatment to modulate efficacy but also to induce colitis. This opens the way for preventive or curative treatments capable of inducing modulation of the microbiota or fecal transplantation.

Biological agents in gastrointestinal cancers: adverse effects and their management

Biological therapy comprises agents that by virtue of their unique mechanisms of action, are able to specifically incite a response against or target malignant cells. They differ from conventional chemotherapy with regard to mechanisms of action, indications and side effect profile. Biologic agents have revolutionized therapy for a number of malignancies. In the setting of gastrointestinal (GI) malignancies, agents targeting vascular endothelial growth factor (VEGF), human epidermal growth factor receptor 2 (Her2/Neu) and epidermal growth factor receptor (EGFR) have proven to be invaluable additions to chemotherapy. However, these agents bring with them a set of side effects attributable to their unique mechanisms of action. The anti VEGF agents-bevacizumab, aflibercept and ramucirumab, can result in renal and vascular complications such as hypertension, arterial thrombotic events (ATE), proteinuria and GI perforations. The anti EGFR agents classically cause dermatological toxicities, in addition to hypomagnesemia, which can be dose limiting for patients. Trastuzumab, a monoclonal antibody that targets Her2/Neu, is known to cause cardiotoxicity, especially when used with anthracyclines. Use of immunotherapy agents such as nivolumab is associated with the development immune related adverse events (irAEs). The use of these agents is expected to increase over the next few years and it is crucial that patients and practitioners are aware of their adverse effects and current management strategies. This review highlights the adverse events associated with the use of biologic and immunologic therapies in GI cancers, their incidence and current management strategies.

Immunological Characteristics of Colitis Associated with Anti-CTLA-4 Antibody Therapy

Anti-CTL4-A therapy is associated with development of colitis. We characterized ipilimumab-associated colitis in nine melanoma patients (6 male, mean age: 55.3-yrs). Median value for diarrhea grade was 2, number of ipilimumab doses 2, and interval since last administration 3-wks. Endoscopic characteristics resembled inflammatory bowel disease and histology revealed predominance of plasmacytes or CD4+ T-cells. We observed significant upregulation of Th1 and Th17 effector pathways (>10-fold increase for IFN-γmRNA, >5-fold for IL-17A, p < 0.01 vs. controls). Significant elevation of FoxP3 was also detected. In conclusion, ipilimumab administration results in elevations of effector lymphocytes and pro-inflammatory mediators in the gut lamina propria.

Inflammatory bowel disease and cancer response due to anti-CTLA-4: is it in the flora?

Checkpoint inhibitors blocking CTLA-4 (ipilimumab) and PD-1 (nivolumab, pembrolizumab) have transfigured our cancer treatment paradigm. However, these drugs can induce immune-related adverse events that share clinical and pathological characteristics with immune-mediated diseases. One of the most severe immune-related adverse event observed with anti-CTLA-4 is an enterocolitis that mirrors naturally occurring inflammatory bowel disease. This paper reviews the clinical, immunological, and microbiota data associated with the immune-related enterocolitis induced by the cancer immunotherapy blocking CTLA-4, ipilimumab. A parallel analysis of the mechanisms underlying inflammatory bowel diseases on the one hand, and anti-CTLA-4-induced colitis on the other hand, stresses the crucial role of the gut microbiota and of resident T_reg in the genesis of both iatrogenic and spontaneous inflammatory bowel diseases.

Auto-immunité et gestion des toxicités des traitements par anti-check point inhibiteurs

AUTOIMMUNITY AND MANAGEMENT OF THE IMMUNE-RELATED ADVERSE EFFECTS OF THE IMMUNE CHECKPOINT INHIBITORS: The immune checkpoint molecules such as CTLA-4 and PD-1 are involved in the tolerance mechanisms preventing the immune system to react against the self-antigens. When these receptors expressed on the lymphocyte membrane, bind to their ligands, they induce a negative signal to the cell which becomes unable to be completely activated in the presence of its antigen. In a context of tumor, the infiltrating T cells are frequently exhausted due to the expression of CTLA-4 and PD-1 ligands by the microenvironment impairing the antitumoral immunity. The use of antagonistic antibodies targeting these receptors or their ligands (called checkpoint inhibitors) aims to block their interaction unbalancing the negative regulation of the antitumoral lymphocytes. However, this effect affects all lymphocytes and may also disrupt the negative regulation of the peripheral autoreactive lymphocytes. Thus, a significant proportion of patients treated by these molecules develop immune-related symptoms affecting different tissues and organs due to lymphocyte activation. These symptoms are called immune-related adverse events (irAEs). This article aims to summarize the scientific data demonstrating the implication of these molecules in the tolerance mechanisms and in the autoimmune diseases. It also reports on the IrAEs observed in treated patients and gives an outline of guidelines to monitor and manage these patients.

Adverse Events in Cancer Immunotherapy

Cancer immunotherapy has resulted in durable responses in patients with metastatic disease, unseen with traditional chemotherapy. Several therapies have been approved by the Food and Drug Administration for the treatment of various cancers, including: immune checkpoint inhibitors, cytokines - interleukin 2 (IL-2) and interferon alpha (IFN), and the cancer vaccine sipuleucel-T. These therapies upregulate the immune system to enhance antitumor responses. As a consequence, they can cause inflammatory and immune-related adverse events that can affect one or more organs, can be serious, and on occasion lifethreatening. The management of these adverse events is complex, and requires a multidisciplinary approach involving not only oncologists, but also other internal medicine specialists, to ensure prompt diagnosis and optimal management of these complications.

PD-1 inhibitor gastroenterocolitis: case series and appraisal of 'immunomodulatory gastroenterocolitis'

AIMS

PD-1 inhibitors facilitate immune response against certain tumour types, including melanoma. These drugs have led to prolonged survival but can also result in autoimmune-type side effects, including gastrointestinal inflammation. The histopathological effects of this medication class have not been well studied.

METHODS AND RESULTS

We identified 37 gastrointestinal tract biopsies from 20 patients taking a PD-1 or PD-L1 inhibitor and evaluated clinicopathological findings. Diarrhoea was the most common symptom, and endoscopic findings ranged from mild erythema to erosion/ulceration. Common histological findings included lamina propria expansion, villous blunting (if applicable), intra-epithelial neutrophils and increased crypt/gland apoptosis, although intra-epithelial lymphocytes were rarely prominent. A few cases showed crypt rupture with resultant histiocytic/granulomatous response. Most patients responded to drug cessation and/or steroids, but follow-up endoscopies were not performed.

CONCLUSIONS

PD-1/PD-L1 inhibitors can cause gastritis, enteritis and colitis, similar to other immunomodulatory antibodies (such as CTLA-4 inhibitors and PI3Kδ inhibitors), but the histological findings vary somewhat among drug classes. Clinical history, lack of prominent intra-epithelial lymphocytes and crypt rupture may help to distinguish PD-1 inhibitor gastroenterocolitis from mimics, which include other medication effect, inflammatory bowel disease, graft-versus-host disease, cytomegalovirus infection and autoimmune enteropathy.

Ipilimumab-induced colitis: experience from a tertiary referral center

BACKGROUND

Ipilimumab is an anticytotoxic T-lymphocyte antigen-4 (CTLA-4) monoclonal antibody used for the treatment of malignant melanoma. It can cause immune-mediated inflammatory adverse events, including diarrhoea and even intestinal perforation or death in clinical trials but there is a dearth of data on postmarketing outcomes.

METHODS

A total of 546 patients attending for treatment of metastatic melanoma between 1 January 2009 and 31 August 2015 were identified by interrogation of the oncology database. A total of 83 of these patients received ipilimumab. Clinical information was extracted from chart reviews, endoscopy and radiology reports, and prescription data.

RESULTS

A total of 83 patients received ipilimumab. Only 19.3% (n = 16) of patients developed a diarrhoeal illness not attributable to other causes. The median grade of diarrhoea among included patients was 2 (range 1-4). In two cases, diarrhoea settled spontaneously without any specific treatment. A total of 87.5% of patients received antidiarrhoeal agents such as loperamide or codeine. These resolved symptoms in all patients with grade 1 diarrhoea. For other treatment, 50% patients received systemic glucocorticosteroids and 31.3% required infliximab. Infliximab resolved symptoms in 100% of cases compared with 50% for systemic glucocorticosteroids.

CONCLUSIONS

The rate of diarrhoea related to ipilimumab in real-world practice is substantial, but below the range observed in data from RCTs. Grade 1 colitis can usually be managed symptomatically, without recourse to stopping ipilimumab. When diarrhoea was grade 2 or above, results from glucocorticosteroids use proved disappointing; but infliximab has been shown to work well. Further research is required into the earlier use of infliximab as an effective treatment for ipilimumab-induced diarrhoea.

Immune checkpoint inhibitors side effects and management

The next decade in cancer therapy will be marked by the expansion of immunotherapies, namely immune checkpoint inhibitors. The increasing number and combination of checkpoint inhibitors and the variety of their mechanisms of action and indications will most likely multiply the side effects associated with these therapies and make their management more complicated and diversified. Given the growing rate of approval of different checkpoint inhibitors in different cancers in multiple settings, a review summarizing the major side effects of the new agents in use today and their management seems to be appropriate. Highlighting these adverse events and their management in a single review might help the daily practice of the physicians and consequently contribute the patient's safety and quality of life.

Ipilimumab (Anti-Ctla-4 Mab) in the treatment of metastatic melanoma: Effectiveness and toxicity management

In the last years the onset of new therapies changed the management of malignant melanoma. Anti CTLA-4 antibody ipilimumab was the first drug to achieve a significant improvement in survival of advanced stage melanoma. This new therapeutic agent is characterized by a number of side effects that are totally different from those of traditional chemotherapy, mainly caused by the immune system activation. The purpose of this paper is to underline the central role of ipilimumab in the treatment of metastatic melanoma and to characterize related adverse events in terms of incidence, duration and severity of presentation. The early recognition of these side effects is crucial in order to ensure an appropriate management of the toxicities, thus reducing the long term clinical sequelae and the inappropriate treatment discontinuation.

How to Diagnose and Treat IBD Mimics in the Refractory IBD Patient Who Does Not Have IBD

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract and includes both Crohn's disease and ulcerative colitis. Patients with IBD often present with abdominal pain, diarrhea, and rectal bleeding but may also have a wide variety of other symptoms such as weight loss, fever, nausea, vomiting, and possibly obstruction. Given that the presentation of IBD is not specific, the differential diagnosis is broad and encompasses a wide spectrum of diseases, many of which can mimic and/or even coexist with IBD. It is important for physicians to differentiate symptoms due to refractory IBD from symptoms due to IBD mimics when a patient is not responding to standard IBD treatment. Many of the various IBD mimics include infectious etiologies (viral, bacterial, mycobacterial, fungal, protozoal, and helminthic infections), vascular causes, other immune causes including autoimmune etiologies, drug-induced processes, radiation-induced, and other etiologies such as small intestinal bacterial overgrowth, diverticulitis, and bile acid malabsorption. Thoughtful consideration and evaluation of these potential etiologies through patient history and physical examination, as well as appropriate tests, endoscopic evaluation, and cross-sectional imaging is required to evaluate any patient presenting with symptoms consistent with IBD.

Cancer Immunotherapy with Anti-CTLA-4 Monoclonal Antibodies Induces an Inflammatory Bowel Disease

BACKGROUND

Therapeutic monoclonal anti-cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) antibodies are associated with immune-mediated enterocolitis. The aim of this study was to provide a detailed description of this entity.

METHODS

We included patients with endoscopic signs of inflammation after anti-CTLA-4 infusions for cancer treatment. Other causes of enterocolitis were excluded. Clinical, biological and endoscopic data were recorded. A single pathologist reviewed endoscopic biopsies and colectomy specimens from 27 patients. Patients with and without enterocolitis after ipilimumab-treated melanoma were compared, to identify clinical factors associated with enterocolitis.

RESULTS

Thirty-nine patients with anti-CTLA-4 enterocolitis were included (ipilimumab n = 37; tremelimumab n = 2). The most frequent symptom was diarrhoea. Ten patients had extra-intestinal manifestations. Most colonoscopies showed ulcerations involving the rectum and sigmoid, 66% of patients had extensive colitis, 55% had patchy distribution and 20% had ileal inflammation. Endoscopic colonic biopsies showed acute colitis in most patients, while half of the patients had chronic duodenitis. Thirty-five patients received steroids that led to complete clinical remission in 13 patients (37%). Twelve patients required infliximab, of whom 10 (83%) responded. Six patients underwent colectomy (perforation n = 5; toxic megacolon n = 1); one of them died postoperatively. Four patients had a persistent enterocolitis at follow-up colonoscopy. Patients with enterocolitis were more frequently prescribed NSAIDs compared with patients without enterocolitis (31 vs 5%, p = 0.003).

CONCLUSIONS

Ipilimumab and tremelimumab may induce a severe and extensive form of inflammatory bowel disease. Rapid escalation to infliximab should be advocated in patients who do not respond to steroids. Patients treated with anti-CTLA-4 should be advised to avoid NSAIDs.

Immune checkpoint inhibitors in lung cancer: past, present and future

Inhibitory ligands on tumor cells and their corresponding receptors on T cells are collectively called immune checkpoint molecules and have emerged as druggable targets that harness endogenous immunity to fight cancer. Immune checkpoint inhibitors targeting CTLA-4, PD-1 and PD-L1 have been developed for the treatment of patients with non-small-cell lung cancer and other malignancies, with impressive clinical activity, durable responses and a favorable toxicity profile. This article reviews the development, current status and future directions for some of these agents. The efficacy and safety data for drugs such as ipilimumab, nivolumab, pembrolizumab, atezolizumab and durvalumab are reviewed, along with combination strategies and response evaluation criteria. The toxicity profiles and predictive biomarkers of response are also discussed.

Intestinal microbiome analyses identify melanoma patients at risk for checkpoint-blockade-induced colitis

The composition of the intestinal microbiota influences the development of inflammatory disorders. However, associating inflammatory diseases with specific microbial members of the microbiota is challenging, because clinically detectable inflammation and its treatment can alter the microbiota's composition. Immunologic checkpoint blockade with ipilimumab, a monoclonal antibody that blocks cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) signalling, is associated with new-onset, immune-mediated colitis. Here we conduct a prospective study of patients with metastatic melanoma undergoing ipilimumab treatment and correlate the pre-inflammation faecal microbiota and microbiome composition with subsequent colitis development. We demonstrate that increased representation of bacteria belonging to the Bacteroidetes phylum is correlated with resistance to the development of checkpoint-blockade-induced colitis. Furthermore, a paucity of genetic pathways involved in polyamine transport and B vitamin biosynthesis is associated with an increased risk of colitis. Identification of these biomarkers may enable interventions to reduce the risk of inflammatory complications following cancer immunotherapy.

A subset of cancer patients treated with immune checkpoint blockade develops colitis. Here the authors show that lower abundance of Bacteroidetes and vitamin B biosynthetic modules in fecal samples of melanoma patients can predict their susceptibility to colitis following anti-CTLA-4 treatment.

Ipilimumab-associated colitis or refractory Clostridium difficile infection?

We present a case of a patient with a diagnostic dilemma who was referred for possible faecal microbiota transplantation (FMT) for refractory diarrhoea secondary to Clostridium difficile infection (CDI). On detailed history, the patient was exposed to ipilimumab concomitantly while being treated for CDI, and was instead diagnosed with diarrhoea secondary to superimposed ipilimumab-associated colitis. Ipilimumab is an anti-CTLA4 monoclonal antibody approved for use in metastatic melanoma and under trial for other indications. Ipilimumab is associated with several immune-related adverse effects, of which diarrhoea and colitis are the most common. While FMT has shown tremendous efficacy in managing recurrent and refractory CDI, it was not offered in this case due to negative C. difficile testing showing a high degree of suspicion for ipilimumab-associated colitis due to recent drug use. Our patient was successfully managed with fluid resuscitation and steroids, and remains symptom free at last follow-up at 9 months.