Checkpoint Inhibitors

Immune Checkpoint Inhibitors and Infection: What Is the Interplay?

Immune checkpoint molecules are receptors expressed on immune cells, especially T-cells, which activate immunosuppressive pathways and lead them to a state known as T-cell exhaustion. Immune checkpoint inhibitors (ICIs) constitute a group of specific antibodies that target these molecules, restoring T-cell effector function. Several ICIs have already been approved by the FDA as therapeutic options for certain malignancies. However, evidence in the literature remains unclear regarding the possible risk of infection in patients receiving this treatment. A thorough examination of existing literature was carried out to investigate whether the use of ICIs increases the likelihood of specific infections and to explore the potential beneficial effects of ICIs on the treatment of infections. Our review found most infectious complications are related to immunosuppressive therapy for immune-related adverse events caused by checkpoint blockade. Current evidence shows that ICIs per se do not seem to generally increase the risk of infection, yet they might increase susceptibility to certain infections, such as tuberculosis. On the other hand, reinvigoration of immune responses triggered by ICIs might play a significant role in pathogen clearance, establishing a possible positive impact of ICIs, especially on chronic infectious diseases, such as HIV infection. Data from preclinical models are limited and larger clinical trials are warranted to shed more light on the effect of immune checkpoint blockade on specific pathogens.

Immune checkpoint inhibitor-induced neurotoxicity is not associated with seroprevalence of neurotropic infections

BACKGROUND

Immune checkpoint inhibitors (ICI) substantially improve outcome for patients with cancer. However, the majority of patients develops immune-related adverse events (irAEs), which can be persistent and significantly reduce quality of life. Neurological irAEs occur in 1-5% of patients and can induce severe, permanent sequelae or even be fatal. In order to improve the diagnosis and treatment of neurological irAEs and to better understand their pathogenesis, we assessed whether previous neurotropic infections are associated with neurological irAEs.

METHODS

Neurotropic infections that might predispose to ICI-induced neurological irAEs were analyzed in 61 melanoma patients from 3 countries, the Netherlands, Australia and Germany, including 24 patients with neurotoxicity and 37 control patients. In total, 14 viral, 6 bacterial, and 1 protozoal infections previously reported to trigger neurological pathologies were assessed using routine serology testing. The Dutch and Australian cohorts (NL) included pre-treatment plasma samples of patients treated with neoadjuvant ICI therapy (OpACIN-neo and PRADO trials; NCT02977052). In the Dutch/Australian cohort a total of 11 patients with neurological irAEs were compared to 27 control patients (patients without neurological irAEs). The German cohort (LMU) consisted of serum samples of 13 patients with neurological irAE and 10 control patients without any documented irAE under ICI therapy.

RESULTS

The association of neurological irAEs with 21 possible preceding infections was assessed by measuring specific antibodies against investigated agents. The seroprevalence of all the tested viral (cytomegalovirus, Epstein-Barr-Virus, varicella-zoster virus, measles, rubella, influenza A and B, human herpes virus 6 and 7, herpes simplex virus 1 and 2, parvovirus B19, hepatitis A and E and human T-lymphotropic virus type 1 and 2), bacterial (Borrelia burgdorferi sensu lato, Campylobacter jejuni, Mycoplasma pneumoniae, Coxiella burnetti, Helicobacter pylori, Yersinia enterocolitica and Y. pseudotuberculosis) and protozoal (Toxoplasma gondii) infections was similar for patients who developed neurological irAEs as compared to control patients. Thus, the analysis provided no evidence for an association of described agents tested for seroprevalence with ICI induced neurotoxicity.

CONCLUSION

Previous viral, bacterial and protozoal neurotropic infections appear not to be associated with the development of neurological irAEs in melanoma patients who underwent therapy with ICI across 3 countries. Further efforts are needed to unravel the factors underlying neurological irAEs in order to identify risk factors for these toxicities, especially with the increasing use of ICI in earlier stage disease.

[Rheumatological side effects of checkpoint inhibitors and their treatment]

The spectrum of tumors for which checkpoint inhibitor (CI) treatment is used is constantly expanding. The European Medicines Agency has currently approved nine CIs: one anti-cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) CI, one anti-lymphocyte activation gene 3 (LAG-3) CI, four anti-programmed cell death protein 1 (PD-1) CIs and three anti-programmed death ligand 1 (PD-L1) CIs. By blocking immune checkpoints the physiological downregulation of T cell activity against autologous tissue is prevented. This results in an immunologically unregulated activation of T cells directed against malignant cells. Healthy tissue also expresses antigens and thereby continuously activates autologous T cells. Thus, the blockade of immune checkpoints can lead to T cell activity against healthy tissue (immune-related adverse events, irAE). The irAEs can occur in any organ system and approximately 10% of all patients under CI treatment develop rheumatological irAEs, mostly arthralgia and myalgia. The classification criteria of rheumatological diseases do not need to be met to initiate treatment and the primary goal of treatment of irAEs is to enable continuation of CI treatment. Rheumatological irAEs should be recognized and treated quickly. In the treatment of musculoskeletal irAEs, three stages can be defined. In the first stage, nonsteroidal anti-inflammatory drugs or intra-articular as well as systemic glucocorticoids are used. In the second stage, conventional synthetic and in the third stage, biologic disease-modifying antirheumatic drugs are used. The most severe musculoskeletal irAE is myositis with cardiac and/or respiratory involvement and/or myasthenia gravis. In addition to high-dose glucocorticoids, intravenous immunoglobulins or plasma exchange are used in treatment.

Management of Immune-Related Adverse Events from Immune-Checkpoint Inhibitors in Advanced or Metastatic Renal Cell Carcinoma

Immune checkpoint inhibitors (ICI) are now, among other cancers, routinely used for the treatment of advanced or metastatic renal cell carcinoma (mRCC). In mRCC various combinations of ICIs and inhibitors of the vascular epidermal growth factor receptor tyrosine kinase (VEGFR-TKIs) as well as dual checkpoint inhibition (nivolumab + ipilimumab), the latter for patients with intermediate and poor risk according to IMDC only (international metastatic renal cell carcinoma database consortium), are now standard of care in the first line setting. Therefore, a profound understanding of immune-related adverse events (irAE) and the differential diagnosis of adverse reactions caused by other therapeutic agents in combination therapies is of paramount importance. Here we describe prevention, early diagnosis and clinical management of the most relevant irAE derived from ICI treatment focusing on the new VEGFR-TKI/ICI combinations.

COVID-19 vaccination in advanced skin cancer patients receiving systemic anticancer treatment: A prospective singlecenter study investigating seroconversion rates

Background

COVID-19 vaccination reduces risk of SARS-CoV-2 infection, COVID-19 severity and death. However, the rate of seroconversion after COVID-19 vaccination in cancer patients requiring systemic anticancer treatment is poorly investigated. The aim of the present study was to determine the rate of seroconversion after COVID-19 vaccination in advanced skin cancer patients under active systemic anticancer treatment.

Methods

This prospective single-center study of a consecutive sample of advanced skin cancer patients was performed from May 2020 until October 2021. Inclusion criteria were systemic treatment for advanced skin cancer, known COVID-19 vaccination status, repetitive anti-SARS-CoV-2-S IgG serum quantification and first and second COVID-19 vaccination. Primary outcome was the rate of anti-SARS-CoV-2-S IgG seroconversion after complete COVID-19 vaccination.

Results

Of 60 patients with advanced skin cancers, 52 patients (86.7%) received immune checkpoint inhibition (ICI), seven (11.7%) targeted agents (TT), one (1.7%) chemotherapy. Median follow-up time was 12.7 months. During study progress ten patients had died from skin cancer prior to vaccination completion, six patients were lost to follow-up and three patients had refused vaccination. 41 patients completed COVID-19 vaccination with two doses and known serological status. Of those, serum testing revealed n=3 patients (7.3%) as anti-SARS-CoV-2-S IgG positive prior to vaccination, n=32 patients (78.0%) showed a seroconversion, n=6 patients (14.6%) did not achieve a seroconversion. Patients failing serological response were immunocompromised due to concomitant hematological malignancy, previous chemotherapy or autoimmune disease requiring immunosuppressive comedications. Immunosuppressive comedication due to severe adverse events of ICI therapy did not impair seroconversion following COVID-19 vaccination. Of 41 completely vaccinated patients, 35 (85.4%) were under treatment with ICI, five (12.2%) with TT, and one (2.4%) with chemotherapy. 27 patients (65.9%) were treated non adjuvantly. Of these patients, 13 patients had achieved objective response (complete/partial response) as best tumor response (48.2%).

Conclusion and relevance

Rate of anti-SARS-CoV-2-S IgG seroconversion in advanced skin cancer patients under systemic anticancer treatment after complete COVID-19 vaccination is comparable to other cancer entities. An impaired serological response was observed in patients who were immunocompromised due to concomitant diseases or previous chemotherapies. Immunosuppressive comedication due to severe adverse events of ICI did not impair the serological response to COVID-19 vaccination.

Kutane Nebenwirkungen unter Immun-Checkpoint-Inhibitor-Therapie

Moderne Immuntherapeutika wie Nivolumab, Pembrolizumab oder Ipilimumab, die sogenannte Immun-Checkpoints blockieren, haben die onkologische Therapie in den letzten Jahren revolutioniert. Mit dem neuen Wirkmechanismus der Blockade wichtiger Kontrollpunkte im Immunsystem zeigen sich jedoch auch eine Vielzahl an unterschiedlichen Nebenwirkungen. Diese treten nicht selten an der Haut auf. Zu den häufigsten dermalen Reaktionen unter Immuntherapie zählen die Vitiligo, Exantheme, blasenbildende Reaktionen oder der Lichen planus. Ausgeprägter Juckreiz kann Patienten stark beeinträchtigen. Der Verlauf bei auf die Haut beschränkten Nebenwirkungen ist häufig mild und gut zu behandeln oder selbstlimitierend. Hauterscheinungen können jedoch auch als Symptom systemischer Reaktionen auftreten. Eine frühe Diagnosestellung, die Einleitung einer adäquaten Therapie sowie eine interdisziplinäre Betreuung bei komplexen Erkrankungen sind entscheidend, um dauerhafte Einschränkungen für die Patienten zu verhindern und eine sichere Behandlung der zugrundeliegenden Tumorerkrankung gewährleisten zu können.

Treatment of patients with cancer using PD‑1/PD‑L1 antibodies: Adverse effects and management strategies (Review)

In 2020, there were an estimated 19.3 million new cancer cases and close to 10 million cancer deaths worldwide. Cancer remains one of the leading causes of death. In recent years, with the continuous improvement of our understanding of tumor immunotherapy, immunotherapeutics, such as immune checkpoint inhibitors, have gradually become a hot spot for tumor treatment. Amongst these, programmed cell death protein 1/programmed cell death protein ligand 1 (PD-1/PD-L1) related inhibitors, such as nivolumab and pembrolizumab, atezolizumab, avelumab and durvalumab have been shown to exhibit a high level of efficacy in several types of tumors. It has been confirmed that these inhibitors play an important role in the anti-tumor process, significantly improving the survival rate of patients and delaying the progress of the underlying cancer. However, its method of therapeutic interference and potential for damaging the immune system has caused concern regarding its suitability. As these adverse effects are caused by an immune response to endogenous tissues, they are designated as immune-related adverse events (irAEs). In this review, the typical irAEs reported in recent years and the management strategies adopted are highlighted, to serve as a reference in assessing the clinical response to these adverse reactions.

Sintilimab-induced autoimmune diabetes: A case report and review of the literature

BACKGROUND

With the widespread application of immune checkpoint inhibitor (ICI) therapy, the number of immune-related adverse effects (irAEs) has increased over the years. Autoimmune diabetes mellitus (DM) is a rare irAEs of ICIs and can be troublesome and life threatening.

CASE SUMMARY

We report a 78-year-old woman with no history of diabetes who presented with hyperglycemia up to 23.4 mmol/L (random blood glucose level) after 14 courses of sintilimab. Hemoglobin A1c was 8.2%, fasting insulin was 0.29 mIU/mL, and fasting C-peptide was decreased to a level with negative autoantibodies. Combing her medical history and laboratory examination, she was diagnosed with programmed cell death (PD)-1-inhibitor-induced, new-onset autoimmune DM. After controlling her blood glucose, she was treated with daily insulin by subcutaneous injection. She was allowed to continue anti-PD-1 therapy and she still obtained some therapeutic efficacy. We also reviewed some published cases (n = 36) of PD-1/PD-ligand 1 (PD-L1) inhibitor-induced DM. We also discuss potential pathogenic mechanisms, clinical features, prognostic markers (β cell antibodies, human leukocyte antigen type, PD-L1 Level) of this rare adverse effect.

CONCLUSION

It is important for all clinicians to be aware of DM as an irAEs of ICIs.

[Management of persistent colitis after successful immunotherapy for non-small cell carcinoma of the lung]

Immune checkpoint inhibitors have shown remarkable efficacy as new-generation drugs in anti-tumor therapy. However, the nonspecific activation of the immune system leads to a number of adverse side effects, so-called immune-related adverse events (irAEs), including the occurrence of diarrhea and colitis in about one third of treated patients.Endoscopically and histologically, there is significant overlap of immune-mediated colitis with classic IBD, making differentiation difficult.Therapeutically, high-dose glucocorticoids are used in grade 3 (severe) to grade 4 (life-threatening) colitis, in addition to discontinuation of ICI therapy. Steroid-refractory cases (up to 42%) benefit from the TNF inhibitor infliximab. Vedolizumab, analogous to inflammatory bowel disease, represents second-line therapy for infliximab-refractory cases. Little data exist to date on the efficacy of tofacitinib in refractory cases.We describe the case and therapeutic management of severe and persistent immune-mediated colitis after successful immunochemotherapy with pembrolizumab in an 80-year-old man with metastatic non-small cell carcinoma of the lung and pre-existing colitis unclassified and other comorbidities.

Grade 4 Neutropenia Secondary to Immune Checkpoint Inhibition - A Descriptive Observational Retrospective Multicenter Analysis

Introduction

Immune checkpoint inhibitors (ICI) are increasingly being used to treat numerous cancer types. Together with improved recognition of toxicities, this has led to more frequent identification of rare immune-related adverse events (irAE), for which specific treatment strategies are needed. Neutropenia is a rare hematological irAE that has a potential for a high mortality rate because of its associated risk of sepsis. Prompt recognition and timely treatment of this life-threatening irAE are therefore critical to the outcome of patients with immune-related neutropenia.

Methods

This multicenter international retrospective study was conducted at 17 melanoma centers to evaluate the clinical characteristics, diagnostics, treatment, and outcomes of melanoma patients with grade 4 neutropenia (<500 neutrophils/µl blood) treated with ICI between 2014 and 2020. Some of these patients received metamizole in addition to ICI (ICI+/met+). Bone marrow biopsies (BMB) of these patients were compared to BMB from non-ICI treated patients with metamizole-induced grade 4 neutropenia (ICI-/met+).

Results

In total, 10 patients (median age at neutropenia onset: 66 years; seven men) with neutropenia were identified, equating to an incidence of 0.14%. Median onset of neutropenia was 6.4 weeks after starting ICI (range 1.4–49.1 weeks). Six patients showed inflammatory symptoms, including fever (n=3), erysipelas (n=1), pharyngeal abscess (n=1), and mucositis (n=1). Neutropenia was diagnosed in all patients by a differential blood count and additionally performed procedures including BMB (n=5). Nine of 10 patients received granulocyte colony-stimulating factors (G-CSF) to treat their grade 4 neutropenia. Four patients received systemic steroids (including two in combination with G-CSF, and one in combination with G-CSF and additional ciclosporin A). Four patients were treated with one or more antibiotic treatment lines, two with antimycotic treatment, and one with additional antiviral therapy. Five patients received metamizole concomitantly with ICI. One fatal outcome was reported. BMB indicated a numerically lower CD4+ to CD8+ T cells ratio in patients with irNeutropenia than in those with metamizole-induced neutropenia.

Conclusion

Grade 4 neutropenia is a rare but potentially life-threatening side effect of ICI treatment. Most cases were sufficiently managed using G-CSF; however, adequate empiric antibiotic, antiviral, and antimycotic treatments should be administered if neutropenic infections are suspected. Immunosuppression using corticosteroids may be considered after other causes of neutropenia have been excluded.

The Continuum of Thyroid Disorders Related to Immune Checkpoint Inhibitors: Still Many Pending Queries

BACKGROUND

Until more data are available to shed light on the thyroid disorders related to immune checkpoint inhibitors (ICPi) implemented for the treatment of hematological malignancies, the decision-making is guided by pertinent data derived mostly from solid tumors.

METHODS

The present review provides a comprehensive and updated overview of the thyroid disorders related to ICPi, namely to inhibitors of cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death (PD) 1 (PD-1), and the ligand of the latter (PD-L1).

RESULTS

With the increasing recognition of ir thyroid disorders, many outstanding issues have emerged. Ir thyroid disorders are reminiscent of, but not identical to, thyroid autoimmunity. Interclass and intraclass ICPi differences regarding thyroid immunotoxicity await interpretation. The available data concerning the predictive value of thyroid autoantibodies for the development of ir thyroid disorders are inconclusive. Mounting data indicate an association of ir thyroid disorders with ICPi efficacy, but a causative link is still lacking. The path forward is a tailored approach, entailing: (i) the validation of tumor-specific, patient-specific, and ICPi-specific predictive factors; (ii) appropriate patient selection; (iii) the uncoupling of antitumor immunity from immunotoxicity; (iv) a multidisciplinary initiative; and (v) global registry strategies.

CONCLUSIONS

Untangling and harnessing the interrelationship of immuno-oncology with endocrinology underlying the ir thyroid disorders will yield the optimal patient care.

[Management of toxicities from immunotherapy]

Immunotherapy with checkpoint inhibitors - monoclonal antibodies targeting cytotoxic T lymphocyte-associated antigen 4 (CTLA4) or the programmed death-1 receptor (PD-1) and its ligand PD-L1 - is now standard of care in the treatment of patients with various tumor types. Therefore, the management of immune-related adverse events (irAEs) has become part of clinical routine.Immune-related adverse events can involve any organ or tissue. They can occur very early within days or weeks after initiation of treatment but can also occur months into treatment and after termination of treatment. Newest data suggest that irAEs can occur until 2 years after stopping therapy.Immune-related adverse events are graded according to Common Terminology Criteria for Adverse Events (CTCAE). Treatment ranges from local or symptomatic treatment, systemic application of corticosteroids to other immunosuppressive agents according to severity.The following article seeks to give a general approach to the management of patients receiving immunotherapy and experiencing irAEs including prevention, diagnostics and treatment.

B7 homologue 3 as a prognostic biomarker and potential therapeutic target in gastrointestinal tumors

The most common digestive system (DS) cancers, including tumors of the gastrointestinal tract (GIT) such as colorectal cancer (CRC), gastric cancer (GC) and esophageal cancer (EC) as well as tumors of DS accessory organs such as pancreatic and liver cancer, are responsible for more than one-third of all cancer-related deaths worldwide, despite the progress that has been achieved in anticancer therapy. Due to these limitations in treatment strategies, oncological research has taken outstanding steps towards a better understanding of cancer cell biological complexity and heterogeneity. These studies led to new molecular target-driven therapeutic approaches. Different in vivo and in vitro studies have revealed significant expression of B7 homologue 3 (B7-H3) among the most common cancers of the GIT, including CRC, GC, and EC, whereas B7-H3 expression in normal healthy tissue of these organs was shown to be absent or minimal. This molecule is able to influence the biological behavior of GIT tumors through the various immunological and nonimmunological molecular mechanisms, and some of them are shown to be the result of B7-H3-related induction of signal transduction pathways, such as Janus kinase 2/signal transducer and activator of transcription 3, phosphatidylinositol 3-kinase/protein kinase B, extracellular signal-regulated kinase, and nuclear factor-κB. B7-H3 exerts an important role in progression, metastasis and resistance to anticancer therapy in these tumors. In addition, the results of many studies suggest that B7-H3 stimulates immune evasion in GIT tumors by suppressing antitumor immune response. Accordingly, it was observed that experimental depletion or inhibition of B7-H3 in gastrointestinal cancers improved antitumor immune response, impaired tumor progression, invasion, angiogenesis, and metastasis and decreased resistance to anticancer therapy. Finally, the high expression of B7-H3 in most common cancers of the GIT was shown to be associated with poor prognosis. In this review, we summarize the established data from different GIT cancer-related studies and suggest that the B7-H3 molecule could be a promising prognostic biomarker and therapeutic target for anticancer immunotherapy in these tumors.

Immunotherapy in hepatocellular carcinoma: evaluation and management of adverse events associated with atezolizumab plus bevacizumab

In light of positive efficacy and safety findings from the IMbrave150 trial of atezolizumab plus bevacizumab, this novel combination has become the preferred first-line standard of care for patients with unresectable hepatocellular carcinoma (HCC). Several additional trials are ongoing that combine an immune checkpoint inhibitor with another agent such as a multiple kinase inhibitor or antiangiogenic agent. Therefore, the range of first-line treatment options for unresectable HCC is likely to increase, and healthcare providers need succinct information about the use of such combinations, including their efficacy and key aspects of their safety profiles. Here, we review efficacy and safety data on combination immunotherapies and offer guidance on monitoring and managing adverse events, especially those associated with atezolizumab plus bevacizumab. Because of their underlying liver disease and high likelihood of portal hypertension, patients with unresectable HCC are at particular risk of gastrointestinal bleeding, and this risk may be exacerbated by treatments that include antiangiogenic agents. Healthcare providers also need to be alert to the risks of proteinuria and hypertension, colitis, hepatitis, and reactivation of hepatitis B or C virus infection. They should also be aware of the possibility of rarer but potentially life-threatening adverse events such as pneumonitis and cardiovascular events. Awareness of the risks associated with these therapies and knowledge of adverse event monitoring and management will become increasingly important as the therapeutic range broadens in unresectable HCC.

Employing Drug Delivery Strategies to Overcome Challenges Using TLR7/8 Agonists for Cancer Immunotherapy

Toll-like receptors (TLRs) are a potential target for cancer immunotherapy due to their role in the activation of the innate immune system. More specifically, TLR7 and TLR8, two structurally similar pattern recognition receptors that trigger interferon and cytokine responses, have proven to be therapeutically relevant targets for cancer in numerous preclinical and clinical studies. When triggered by an agonist, such as imiquimod or resiquimod, the TLR7/8 activation pathway induces cellular and humoral immune responses that can kill cancer cells with high specificity. Unfortunately, TLR7/8 agonists also present a number of issues that must be overcome prior to broad clinical implementation, such as poor drug solubility and systemic toxic effects. To overcome the key limitations of TLR7/8 agonists as a cancer therapy, biomaterial-based drug delivery systems have been developed. These delivery devices are highly diverse in their design and include systems that can be directly administered to the tumor, passively accumulated in relevant cancerous and lymph tissues, triggered by environmental stimuli, or actively targeted to specific physiological areas and cellular populations. In addition to improved delivery systems, recent studies have also demonstrated the potential benefits of TLR7/8 agonist co-delivery with other types of therapies, particularly checkpoint inhibitors, cancer vaccines, and chemotherapeutics, which can yield impressive anti-cancer effects. In this review, we discuss recent advances in the development of TLR7/8 agonist delivery systems and provide perspective on promising future directions.

The Diagnosis and Management of Endocrine Side Effects of Immune Checkpoint Inhibitors

BACKGROUND

The immunologically mediated side effects of immune checkpoint inhibitors (CPI) often involve the endocrine system as well, and they can even be fatal, as in the case of unrecognized hypophysitis. Distinguishing such side effects from tumor-related changes is often difficult, because their clinical features can be nonspecific.

METHODS

This review is based on publications retrieved by a selective search in PubMed, with special attention to international recommendations.

RESULTS

Depending on their target molecules, the CPI now in use differ from one another in the incidence of side effects such as autoimmune thyroid disease (4-16%), hypophysitis (0.1- 18%), adrenalitis (0.7-8%), and autoimmune diabetes mellitus (0.5-2%). The typical clinical warning signs and laboratory constellations of hypophysitis include exhaustion, hyponatremia, and headache. Hypo- and hyperthyroidism and primary adrenocortical insufficiency likewise have nonspecific manifestations. Autoimmune diabetes mellitus often takes a fulminant course. Patients being treated with CPI should be monitored at close intervals, at least as frequently as the administration of the drug, so that endocrine side effects can be recognized in time. In case of doubt, glucocorticoid supplementation should be given whenever hypocortisolism is suspected, even before endocrine evaluation is completed and the results are available. Interrupting or discontinuing CPI treatment is rarely indicated.

CONCLUSION

With the increasing number of patients being treated with CPI, more and more physicians from a wide variety of specialties, not necessarily working in specialized centers, now have to consider immunologically mediated endocrine side effects in the differential diagnosis, and treat them properly when they arise. These things should be done in collaboration with endocrinologists. The ongoing study of such side effects of the CPI now in use, and of those that will be introduced in the future, is important and will lead to improved understanding.

[Side effects of immune checkpoint inhibitor treatment of urological tumors]

Immune checkpoint inhibitors (ICI) are currently routinely used for the treatment of advanced or metastatic urothelial and renal cell carcinomas. Furthermore, several clinical trials are currently investigating their role in adjuvant and neoadjuvant settings as well as in high-risk non-muscle-invasive bladder cancer. As a result, urologists are increasingly confronted with patients who are currently receiving, have recently received or will receive ICI treatment. Care is often interdisciplinary, with urologists playing a central role. Therefore, a profound understanding of immune-mediated adverse events and their differential diagnoses with respect to side effects of other medications in combination treatment are therefore extremely important. This article focusses on the prevention, early diagnosis and clinical management of the most relevant immune-related side effects derived from the new VEGFR-TKI/ICI combinations.

Inflammatory markers in autoimmunity induced by checkpoint inhibitors

PURPOSE

Immune checkpoint inhibitors (ICI) are highly effective in several cancer entities, but also invoke a variety of immune-related adverse events (irAE). These are mostly reversible, but can be life-threatening or even fatal. Currently, the pathogenesis is not fully understood, but crucial for effective treatment. Prediction and early detection of irAE could be facilitated and treatment optimized if relevant biomarkers and effector mechanisms were better characterized.

METHODS

This study included a total of 45 irAE in patients with metastatic melanoma who were treated with ICI. All patients underwent a complete work-up with exclusion of other causes. Longitudinal blood samples were analyzed for a panel of soluble markers and compared to baseline and to patients who did not experience any irAE. Measurements included LDH, interleukin (IL)-6, IL-1β, IL-17, C-reactive protein (CRP) and tumor necrosis factor (TNF)-alpha as well as tumor markers S100 and melanoma inhibitory activity (MIA).

RESULTS

During the early onset of irAE increases in serum IL-6 (from mean 24.4 pg/ml at baseline to 51.0 pg/ml; p = 0.003) and CRP (from mean 7.0 mg/l at baseline to 17.7 mg/l; p = 0.001) and a decrease in MIA (from mean 5.4 pg/ml at baseline to 4.8 pg/ml; p = 0.035) were detected. No changes in IL-17 were noted. These effects were observed for irAE of different organ systems.

CONCLUSION

Increases of a combination of IL-6 and CRP serum levels can be used for the early detection of irAE and tailored management. Interestingly, changes in MIA serum levels also correlate with irAE onset.

The potential applications of T cell receptor (TCR)-like antibody in cervical cancer immunotherapy

Cervical cancer is ranked as the fourth most common cancer in women worldwide. Monoclonal antibody has created a new dimension in the immunotherapy of many diseases, including cervical cancer. The antibody's ability to target various aspects of cervical cancer (oncoviruses, oncoproteins, and signaling pathways) delivers a promising future for efficient immunotherapy. Besides, technologies such as hybridoma and phage display provide a fundamental platform for monoclonal antibody generation and create the opportunity to generate novel antibody classes including, T cell receptor (TCR)-like antibody. In this review, the current immunotherapy strategies for cervical cancer are presented. We have also proposed a novel concept of T cell receptor (TCR)-like antibody and its potential applications for enhancing cervical cancer therapeutics. Finally, the possible challenges in TCR-like antibody application for cervical cancer therapeutics have been addressed, and strategies to overcome the challenges have been highlighted to maximize the therapeutic benefits.

Factors Influencing the Adjuvant Therapy Decision: Results of a Real-World Multicenter Data Analysis of 904 Melanoma Patients

Adjuvant treatment of melanoma patients with immune-checkpoint inhibition (ICI) and targeted therapy (TT) significantly improved recurrence-free survival. This study investigates the real-world situation of 904 patients from 13 German skin cancer centers with an indication for adjuvant treatment since the approval of adjuvant ICI and TT. From adjusted log-binomial regression models, we estimated relative risks for associations between various influence factors and treatment decisions (adjuvant therapy yes/no, TT vs. ICI in BRAF mutant patients). Of these patients, 76.9% (95% CI 74-80) opted for a systemic adjuvant treatment. The probability of starting an adjuvant treatment was 26% lower in patients >65 years (RR 0.74, 95% CI 68-80). The most common reasons against adjuvant treatment given by patients were age (29.4%, 95% CI 24-38), and fear of adverse events (21.1%, 95% CI 16-28) and impaired quality of life (11.9%, 95% CI 7-16). Of all BRAF-mutated patients who opted for adjuvant treatment, 52.9% (95% CI 47-59) decided for ICI. Treatment decision for TT or ICI was barely associated with age, gender and tumor stage, but with comorbidities and affiliated center. Shortly after their approval, adjuvant treatments have been well accepted by physicians and patients. Age plays a decisive role in the decision for adjuvant treatment, while pre-existing autoimmune disease and regional differences influence the choice between TT or ICI.

Retrospective Analysis of Checkpoint Inhibitor Therapy-Associated Cases of Bullous Pemphigoid From Six German Dermatology Centers

Immune-related adverse events (irAEs) are a class-effect of checkpoint inhibitors (CIs). The development of a Bullous pemphigoid (BP)-like blistering disease, driven by autoantibodies against the hemidesmosomal protein BP180, is a potentially serious irAE whose incidence seems to be increasing. We therefore set out to characterize the clinical and (immuno)histopathological features and treatment responses of cases of BP which developed during or after CI therapy collated in six German tertiary referral centers between 2014 and 2018. We identified twelve cases of BP which emerged during and/or after CI therapy. The time interval between the initiation of CI therapy and the diagnosis of BP was 3-74 weeks (median: 23 weeks). Age at the time of diagnosis of BP varied between 62 and 80 years (median: 76 years). The clinical presentation of the patients was diverse but the severity was relatively mild when compared to that seen in most cases of spontaneous BP. Only four patients met all of the immunopathological criteria recommended in the European guidelines for the diagnosis of BP. Topical corticosteroid treatment was sufficient to achieve disease control in most patients. CI therapy could be continued in 8 out of 12 patients. In summary, our study indicates that cases of BP during or after CI therapy bear several peculiarities distinguishing them from spontaneous BP. Given the diversity of the clinical presentation of CI-induced BP the application of existing diagnostic algorithms developed for spontaneous BP can be utilized to uncover the frequency and features of CI-induced BP and to develop and optimize management algorithms.

Nebenwirkungen immunonkologischer Therapien

Immunonkologische Therapien und insbesondere die Immuncheckpoint-Inhibitoren (ICPi) als Hauptvertreter dieser neuen Substanzklasse kommen bei zunehmender Anzahl von soliden und teils auch hämatologischen Tumorentitäten und Indikationen zum Einsatz. Die relativ hohen (Langzeit-)Tumoransprechraten auch in fortgeschrittenen und therapierefraktären Stadien haben die therapeutischen Möglichkeiten der Onkologie geradezu revolutioniert. Gleichzeitig bringt der zunehmende Einsatz von ICPi auch neue Herausforderungen: Immunonkologische Therapien verursachen ein breites Spektrum an autoimmunen Nebenwirkungen, sogenannten „immune-related adverse events“ (irAEs), die teilweise klassischen Autoimmunopathien ähneln und jedes Organsystem betreffen können. Die große Mehrheit der ICPi-behandelten Patienten erlebt ein irAE an mindestens einem Organsystem und davon weisen ca. 5–20% ein rheumatisches irAEs auf. Diese sind interessanterweise mit einem besseren Tumoransprechraten bei ICPi-Therapie assoziiert und können entweder die Erstmanifestation einer klassischen entzündlich-rheumatischen Erkrankung oder auch nur eine transiente Nebenwirkung mit spezifischen Charakteristika sein. Zweifelsohne wird das interdisziplinäre Management immunvermittelter Nebenwirkungen auch den Rheumatologen in den nächsten Jahren zunehmend beschäftigen. Der vorliegende Artikel fasst die Erkenntnisse zum klinischen Management von irAEs für den praktizierenden Rheumatologen zusammen.

Analysis of immune-related adverse events caused by immune checkpoint inhibitors using the Japanese Adverse Drug Event Report database

PURPOSE

The aim of our study was to characterize the clinical features of immune-related adverse events (irAEs) associated with immune checkpoint inhibitors (ICIs) in a real-world setting using the Japanese Adverse Drug Event Report (JADER) database.

METHODS

The irAEs were defined using the preferred terms of the Medical Dictionary for Regulatory Activities. irAEs were categorized as follows: adrenal insufficiency, colitis, eye diseases, hematological disorder, hepatitis, hyperthyroidism, hypopituitarism, hypothyroidism, myasthenia gravis, myocarditis, nephritis/renal dysfunction, pneumonitis, rash, and type 1 diabetes mellitus. We used several indices such as reporting odds ratio (ROR) to assess disproportionality in pharmacovigilance data, time-to-onset analysis using Weibull shape parameters, and the association rule mining technique to evaluate possible risk factors between variables in the spontaneous reporting system database.

RESULTS

The JADER database contained 534 688 reports from April 2004 to June 2018. The RORs of pneumonitis including interstitial lung disease for nivolumab, pembrolizumab, and ipilimumab were 7.02 (95% confidence interval: 6.55-7.52), 9.08 (8.28-9.97), and 1.74 (1.27-2.38), respectively. The median onsets (quartiles, 25-75%) of myocarditis caused by nivolumab and pembrolizumab were 28.0 (15.5-60.5) and 18.0 (13.0-44.5) days, respectively. Co-therapy with nivolumab and ipilimumab may be associated with irAEs in several categories as per the association rule mining analysis.

CONCLUSION

Our results demonstrated a potential risk of irAEs associated with ICIs, based on RORs and time-to-onset analysis. Furthermore, our findings indicated that patients receiving nivolumab and ipilimumab as co-therapy should be carefully monitored.

Opportunities for using in silico-based extended dosing regimens for monoclonal antibody immune checkpoint inhibitors

Therapeutic drug monitoring (TDM) involves frequent measurements of drug concentrations to ensure levels remain within a therapeutic window, and it is especially useful for drugs with narrow therapeutic indices or extensive interindividual pharmacokinetic variability. This technique has never been applied to immuno-oncology drugs, but, given recent examinations of clinical data (both exposure and response) on a number of these drugs, further investigations into TDM may be justified to reduce costs as well as potentially reducing the severity and/or duration of immune-related adverse events. Specifically, all but one of the approved PD-1 and PD-L1 inhibitors (pembrolizumab, nivolumab, cemiplimab-rwlc, atezolizumab, avelumab, durvalumab) have been shown to exhibit a plateaued exposure-response (E-R) curve at doses evaluated extensively to date, as well as time-dependent changes in drug exposure. Furthermore, responders have a greater decrease in drug clearance over time and would, therefore, have supratherapeutic serum concentrations. With frequent trough measurements, it is possible to use pharmacokinetic modelling and simulation to estimate drug clearance via Bayesian methods. Based on patient-specific estimates for clearance, optimal alternative dosing strategies can be simulated to lower drug and cost burden yet maintain therapeutic levels, especially as the clearance of the drug decreases over time. This review will comprehensively discuss each of the FDA approved PD-1, PD-L1/2 and CTLA-4 inhibitors regarding their indications and current recommended dosing, with evidence supporting the investigation of these types of TDM strategies.

PD-L1 Checkpoint Inhibition Narrows the Antigen-Specific T Cell Receptor Repertoire in Chronic Lymphocytic Choriomeningitis Virus Infection

Checkpoint inhibitors are effective in restoring exhausted CD8⁺ T cell responses in persistent viral infections or tumors. Several compounds are in clinical use for different malignancies, but trials in patients with chronic viral infections have also been conducted. In a mouse model of persistent lymphocytic choriomeningitis virus (LCMV) infection, it was shown that checkpoint inhibitor treatment increased T cell proliferation and functionality, but its influence on the antigen-specific T cell receptor (TCR) repertoire is unknown. NP396-specific CD8⁺ T cells dominate during acute LCMV infection and are predominantly exhausted during chronic infection. Next-generation sequencing of NP396-specific TCRs showed that exhaustion corresponds with a significantly reduced NP396-specific TCR repertoire diversity: Shannon indices of 4 in immunized mice to 2.6 in persistently infected mice. Anti-PD-L1 treatment during persistent LCMV infection restored NP396-specific T cell responses and reduced viral titers. Nevertheless, anti-PD-L1-treated mice showed an even more narrowed TCR repertoire, with reduced TCR diversity compared to that of persistently infected control mice (Shannon indices of 2.1 and 2.6, respectively). Interestingly, anti-PD-L1 treatment-induced narrowing of the TCR repertoire negatively correlates with functional and physical restoration of the antigen-specific T cell response. Further, we found that private, hyperexpanded TCR clonotypes dominated the T cell response after anti-PD-L1 treatment. Although being private, these top clonotypes from anti-PD-L1-treated mice revealed a more closely related CDR3 motif than those of top clonotypes from persistently infected control mice. In conclusion, although targeting the PD-1/PD-L1 pathway reinvigorates exhausted CD8⁺ T cells, it fails to restore T cell repertoire diversity.IMPORTANCE Checkpoint inhibitors are effective immunotherapeutics to restore cancer- and virus-induced exhausted CD8⁺ T cells, by enhancing the quality and survival of immune responses. Although checkpoint inhibitors are already used as therapy against various cancers, not much is known about their multifaceted impact on the exhausted CD8⁺ T cell receptor (TCR) repertoire. This report describes for the first time the evolvement of an exhausted antigen-specific CD8⁺ TCR repertoire under checkpoint inhibitor treatment. By using a well-established virus model, we were able to show major shifts toward oligoclonality of the CD8⁺ TCR repertoire response against a massively exhausted lymphocytic choriomeningitis virus (LCMV) epitope. While supporting viral control in the LCMV model, oligoclonality and more private of TCR repertoires may impact future pathogenic challenges and may promote viral escape. Our results may explain the ongoing problems of viral escapes, unpredictable autoimmunity, and heterogeneous responses appearing as adverse effects of checkpoint inhibitor treatments.

The Systemic Treatment of Melanoma

BACKGROUND

The systemic treatment of metastatic melanoma has improved considerably with the introduction of new, targeted substances and immune checkpoint inhibitors. This article presents treatment options for advanced inoperable melanoma and in the setting of adjuvant treatment after complete metastasectomy.

METHODS

The data for analysis were derived from a selective literature search in PubMed and a search for systematic reviews in the Cochrane Library.

RESULTS

Immune checkpoint inhibitors, which target the cytotoxic T-lymphocyte antigen or the "programmed death" (PD) receptor, activate T-cells and other immune cells, so that the body's own immune system attacks the melanoma. In unselected patients, immune checkpoint inhibition using nivolumab improved overall survival compared with dacarbazine (hazard ratio [HR]: 0.42; P<0.001). The antibody pem- brolizumab also led to better overall survival than ipilimumab (HR 0.68; P<0.001). Combination treatment with anti-CTLA-4 and anti-PD-1 antibodies improved overall survival even more than ipilimumab monotherapy, albeit at the cost of greater toxic- ity (HR 0.55; P<0.001). Another treatment approach aims to inhibit intracellular signal transduction in the melanoma cells. For patients with a BRAF-V66 mutation, combination treatments with BRAF/MEK inhibitors led to a rapid response in most cases (64-75%). In principle, the novel treatments are also effective in patients with cerebral metastases. In the adjuvant setting, both immune checkpoint inhibitors and BRAF/MEK inhibitors reduced the risk of recurrence by about 50%.

CONCLUSION

High-quality studies show that the new substances are clinically effective in the palliative and adjuvant treatment of melanoma.

Immune Checkpoint Inhibitor-Induced Acute Pancreatitis and Colitis

Given the promising response of immune checkpoint inhibitors (ICPIs) in treating advanced malignancies, their use in clinical practice is on the rise. ICPIs are associated with a wide spectrum of immune-related adverse events (irAEs). The reported side effects of therapy can be severe enough to require interruption or withdrawal. We are presenting a case of a checkpoint inhibitor-induced acute pancreatitis and colitis, treated with high-dose steroids. This case highlights the need for all physicians to be aware of the different presentations of irAEs from checkpoint inhibitors to provide the correct diagnosis and management.

[Side effects of novel cancer immunotherapies]

Systemic treatment with immune checkpoint inhibitors (ICI) has revolutionized the treatment of hematological and oncological diseases in recent years. The mechanism of action hinges on enhancing the natural ability of the immune system to eliminate malignant cells. The most important substances in this arena include inhibitors of PD‑1, PD-L1 and CTLA‑4. As a consequence, the spectrum of treatment-associated adverse reactions is shifting away from classical cytotoxic effects (e.g. pancytopenia and polyneuropathy) towards novel entities of immune-mediated complex diseases. These so-called immune-related adverse events (irAEs) can involve any organ system and mimic known classical autoimmune conditions. Timely recognition of irAEs is the key for rapid initiation of a suitable treatment and is especially challenging in the clinical routine as it requires an intensive interdisciplinary management. Nephrologists are particularly confronted with this kind of problem due to the highly interdisciplinary nature of their work. This article summarizes the broad spectrum of currently known renal and more frequently occuring non-renal forms of irAEs and aims to prime the reader on diagnostic and therapeutic options.

[Supportive therapy and management of side effects in dermato-oncology]

In the context of supportive therapy, possible complaints which may be caused by the cancer itself, by the antitumoral therapy or by psychosocial concerns are considered. Due to the introduction of new anticancer drugs in dermato-oncology, clinicians are confronted with a novel spectrum of adverse events. There are a number of inflammatory, immune-mediated side effects caused by immunotherapies, which can affect virtually any organ. Targeted therapies also have specific side effects. Basically, the management of adverse events depends on their severity. Besides treatment breaks and dosage modifications, immunotherapy-related adverse events are treated with systemic immunosuppressants. Supportive symptomatic therapy is offered. The additional consideration of psychosocial problems can improve quality of life of cancer patients.

Recurrence of Pemphigus Vulgaris Under Nivolumab Therapy

For many types of cancer, immune checkpoint inhibitors have proven to be a highly effective treatment. The monoclonal anti-PD-1 antibody nivolumab stimulates the immune system and is one of the newest treatment options for non-small cell lung cancer. In doing so, immune checkpoint inhibitors can trigger many skin lesions that have not yet been completely investigated in their entirety. In this case report, pemphigus vulgaris is identified as a potential adverse event that occurs under the treatment with nivolumab. In addition to the standard methods, we examined our patient's samples with ex vivo confocal laser scanning microscopy. This is a new and innovative diagnostic method that uses vertical scanning to provide fast, high-resolution imaging of freshly excised tissue, even using fluorescently labeled antibodies.

Nivolumab plus Carboplatin and Paclitaxel as the First-line Therapy for Advanced Squamous Cell Carcinoma of the Lung with Strong Programmed Death-ligand 1 Expression: A Case Report

An 80-year-old male patient was diagnosed to have squamous cell carcinoma of the lung which had a high level of programmed death-ligand 1 (PD-L1) expression. He was prescribed with intravenously administered nivolumab combined with carboplatin and paclitaxel as the first-line therapy. A rapid remission was achieved with nearly total necrosis and cavitation of the original tumor. However, the successful treatment result was accompanied with pneumonitis most likely as an adverse effect of nivolumab. After discontinuation of nivolumab and starting prednisolone treatment, the pneumonitis was soon brought under control. During the treatment course, temporary exacerbation of the disease status led to an interesting differential diagnosis between hyperprogression and pseudoprogression. Tremendous efficacy of combination immunochemotherapy as the first-line treatment for squamous non-small cell lung cancer (NSCLC) with highly expressed PD-L1 has been well demonstrated in this case.

The Diverse Function of PD-1/PD-L Pathway Beyond Cancer

The recent success of PD-1 and PD-L1 blockade in cancer therapy illustrates the important role of the PD-1/PD-L1 pathway in the regulation of antitumor immune responses. However, signaling regulated by the PD-1/PD-L pathway is also associated with substantial inflammatory effects that can resemble those in autoimmune responses, chronic infection, and sepsis, consistent with the role of this pathway in balancing protective immunity and immunopathology, as well as in homeostasis and tolerance. Targeting PD-1/PD-L1 to treat cancer has shown benefits in many patients, suggesting a promising opportunity to target this pathway in autoimmune and inflammatory disorders. Here, we systematically evaluate the diverse biological functions of the PD-1/PD-L pathway in immune-mediated diseases and the relevant mechanisms that control these immune reactions.