Long-term safety of siltuximab in patients with idiopathic multicentric Castleman disease: a prespecified, open-label, extension analysis of two trials

[Siltuximab as a salvage therapy in multi-refractory adult-onset Still's disease: A case series]

INTRODUCTION

Adult-onset Still's disease (AOSD) is a systemic auto-inflammatory disorder characterized by a cytokine storm. Four major cytokines can be specifically targeted in severe, refractory or corticosteroid-dependent forms: interleukin 1 (IL-1), interleukin 6 (IL-6), interleukin 18 (IL-18), and Tumor necrosis factor alpha (TNFa). According to the French national protocol for adult-onset Still's disease, anti-IL-6 agents are the second-line of treatment after corticosteroids. We report here on the efficacy and safety of siltuximab prescribed off-label in patients with multi-refractory forms.

OBSERVATIONS/RESULTS

These 4 patients, aged 24 to 74 years old, had polycyclic and inflammatory AOSD. The introduction of siltuximab was proposed after failure or poor tolerance of several lines of treatment. A partial or complete clinico-biological response was observed in all 4 patients.

CONCLUSION

Siltuximab is a possible salvage treatment for multi-refractory AOSD.

Haemophagocytic lymphohistiocytosis in HIV-associated HHV-8-positive multicentric Castleman disease

OBJECTIVE

The clinical and laboratory characteristics of HHV-8-associated multicentric Castleman disease (MCD) in people with HIV (PWH) overlap with those of haemophagocytic lymphohistiocytosis (HLH) disease and indeed the two diagnoses may co-exist. A risk-stratified treatment approach to MCD based on Rituximab immunotherapy for mild cases and chemo-immunotherapy for severe cases has been shown to yield excellent outcomes in PWH. In contrast, HLH disease, previously known as secondary HLH, has a dismal prognosis even when promptly treated according to guidelines.

DESIGN

A retrospective multicentre cohort study.

METHODS

Retrospective analysis of prospectively collected clinical and pathological data on patients with biopsy-proven HIV-associated MCD at the National Centre for HIV Malignancy at Chelsea and Westminster Hospital, London between 2008 and 2024 and at the Department of Infectious Diseases at St. Joseph Hospital Berlin-Tempelhof, Germany between 2020 and 2024.

RESULTS

In our UK-German cohort, including 113 PWH with MCD, we confirmed that HLH disease secondary to MCD is common (30%), and we demonstrated that HLH disease in this context does not adversely influence survival or risk of MCD relapse.

CONCLUSION

We suggest that a high HScore in MCD should not lead to a change in the treatment in this specific setting.

Diagnostic challenges in patients with Castleman disease, a single center experience from Hungary

Castleman disease is a rare and atypical lymphoproliferative disorder characterized by diverse clinical manifestations. It has both unicentric and multicentric forms, the latter with further subdivisions, i.e., human herpesvirus 8-associated and idiopathic forms. The diagnosis of Castleman disease is often delayed, as it is rare, and because it shares clinical features with different autoimmune, inflammatory, and malignant lymphoproliferative disorders. The first-line treatment in unicentric form is mainly surgical, while in idiopathic Castleman disease, anti-interleukin-6 treatment is the therapy of choice. In virus-associated diseases, antiretroviral therapy and rituximab are recommended. In Hungary, only a few cases of Castleman disease have been published. This report presents our two decades of experience in the challenging diagnosis and management of this rare disorder, most properly underdiagnosed in Hungary. We provide insights into seven unicentric and five idiopathic multicentric Castleman disease cases, the latter ones especially highlighting the diagnostic and therapeutic challenges due to the variable and unique clinical features both of patients and diseases, e.g., bronchiolitis obliterans, stage IV diabetic renal failure, anti-HBc positivity, siltuximab treatment period, respectively.

Real-practice management and treatment of idiopathic multicentric Castleman disease with siltuximab: a collection of clinical experiences

Castleman disease (CD) is a group of lymphoproliferative disorders that share common histopathological features yet have widely different aetiologies, clinical features and grades of severity as well as treatments and outcomes. Siltuximab is currently the only therapy approved by the FDA and EMA for idiopathic multicentric CD and is recommended as first-line therapy in treatment guidelines. Despite the extensive characterization of siltuximab treatment in clinical trials, available evidence from real-world practice is still scant. This collection of clinical experiences focuses on patients treated with siltuximab therapy, particularly regarding the idiopathic multicentric CD diagnostic work-up, and on treatment administration in patients with complex disease entering differential diagnosis with CD or concomitant diseases. Thus, these data help further characterize and improve the use of siltuximab in real practice in terms of effectiveness and safety of long-term administration as well as consequences of treatment interruption.

Clinical features and outcomes in patients with human immunodeficiency virus-negative, Castleman's disease: a single medical center study in Tunisia

INTRODUCTION

Castleman's disease (CD), known as angiofollicular lymph node hyperplasia, is an uncommon condition. The two most common histological subtypes are hyaline vascular and plasma cell. We performed a retrospective analysis to define the clinic-pathological features and survival of CD, which is quite rare focusing on the particularities of our series with a review of the recent literature.

METHODS

This is a retrospective study conducted in the department of internal medicine of Hedi Chaker hospital in Sfax, Tunisia over 25 years. The disease was histologically confirmed in all patients. For each file, we collected a set of data by filling in a pre-designed form.

RESULTS

18 patients were included. There were 8 men and 10 women with a mean age of 42.8 years. CD was monocentric in 5 cases (28%) and multicentric in 13 cases (72%). Clinically, peripheral adenopathy was present in 77.7% of patients and deep adenopathy in 72.2%. Systemic signs were found in 13 patients, including general condition (4.4%), fever (16.6%), serositis (27.7%), and skin involvement (33.3%). A biological inflammatory syndrome accompanied the clinical picture in 66% of patients. Abnormalities in the blood count were found in 12 cases (66%), with anemia in 11 cases, thrombocytosis in 3 cases, and hypereosinophilia in 3 cases. Cutaneous Kaposi's sarcoma was associated with Castleman's disease in 2 cases, Hodgkin's lymphoma, angioimmunoblastic T-cell lymphoma, and lymph node T-cell lymphoma were found in 1 case respectively. 3 of the patients had associated connective tissue diseases such as Sjögren's syndrome in 2 cases and rheumatoid arthritis in 1 case. HHV8 serology was positive in 1 case with a multicentric plasma cell form. Histologically, the plasma cell form represented 50% of cases, hyaline-vascular (39% of cases), and mixed (11% of cases). Therapeutically, high-dose corticosteroid therapy was initiated in 13 cases. As a second-line treatment, MOPP chemotherapy was used in 1 case due to transformation into Hodgkin's lymphoma, and biotherapy (rituximab) was used in 2 cases in the multicentric form. Surgical removal of superficial adenopathy was performed in 2 patients with monocentric CD.

CONCLUSION

: Castleman's disease (CD) is a non-malignant lymphoproliferation of localized or multicentric form with a wide and heterogeneous clinical spectrum. Diagnosis can be difficult due to the lack of clinical and radiological specificity. Management depends on the clinical form involving surgical and/or medical management.

Idiopathic multicentric Castleman disease: An update in diagnosis and treatment advances

Idiopathic multicentric Castleman disease (iMCD) is a rare disease, and it is likely underdiagnosed because of the heterogeneity of clinical manifestations and laboratory findings. While the disease leads to significant morbidity and mortality, its causes are not yet fully elucidated. There have been significant advances in diagnosis and treatment of iMCD in the past decade, including the approval of the anti-IL-6 antibody siltuximab. In this review, we provide an update of the many new developments and publications surrounding iMCD.

Treatment consistent with idiopathic multicentric Castleman disease guidelines is associated with improved outcomes

Idiopathic multicentric Castleman disease (iMCD) is a rare hematologic disorder with an unknown etiology. Clinical presentation is heterogeneous, ranging from mild constitutional symptoms with lymphadenopathy to life-threatening multiorgan dysfunction. International, consensus treatment guidelines developed in 2018 relied upon a limited number of clinical trials and small case series; however, to our knowledge, real-world performance of these recommendations has not been subsequently studied. Siltuximab, a monoclonal antibody against interleukin 6 (IL6), is approved for the treatment of iMCD and recommended first-line, and tocilizumab, a monoclonal antibody directed against the IL6 receptor, is recommended when siltuximab is unavailable. Chemotherapy, rituximab, and immunomodulators are recommended as second- and third-line treatments based on limited evidence. Corticosteroid monotherapy is used by clinicians, although not recommended. Here, we draw upon the ACCELERATE Natural History Registry to inventory regimens and evaluate regimen response for 102 expert-confirmed iMCD cases. Siltuximab with/without (w/wo) corticosteroids was associated with a 52% response, whereas corticosteroid monotherapy was associated with a 3% response. Anti-IL6-directed therapy with siltuximab or tocilizumab demonstrated better response and more durability than was observed with rituximab w/wo corticosteroids. Cytotoxic chemotherapy was associated with a 52% response and was predominantly administered in patients characterized by thrombocytopenia, anasarca, fever, renal failure/reticulin fibrosis, and organomegaly. Our results provide evidence in support of current recommendations to administer anti-IL6 as first-line treatment, to administer cytotoxic chemotherapy in patients with severe refractory disease, and to limit corticosteroid monotherapy. Evidence remains limited for effective agents for patients who are refractory to anti-IL6-directed therapy. This trial was registered at www.clinicaltrials.gov as #NCT02817997.

Unmet Clinical Needs in the Management of Idiopathic Multicentric Castleman Disease: A Consensus-based Position Paper From an ad hoc Expert Panel

Castleman disease describes a group of heterogeneous clinicopathological disorders now included in the tumor-like lesions with B-cell predominance of the World Health Organization classification. Managing idiopathic multicentric Castleman disease (iMCD) is challenging, because few systematic studies or comparative randomized clinical trials have been conducted. International, consensus evidence-based guidelines for iMCD were published in 2018, but gaps in the therapeutic options for difficult-to-treat patients, who do not respond to siltuximab and other conventional therapies, still exist. This article presents the results of group discussion among an ad hoc constituted Panel of Italian experts to identify and address unmet clinical needs (UCNs) in managing iMCD. Recommendations on the appropriateness of clinical decisions and proposals for new research concerning the identified UCNs were issued through formalized multiple-step procedures after a comprehensive analysis of the scientific literature. The following key UCNs were addressed: strengthening the diagnostic certainty in iMCD patients before planning first-line therapy; management of siltuximab therapy; choice and management of immune-modulating, or chemotherapy agents in patients resistant/intolerant to siltuximab therapy. While most of the conclusions reached by the Panel are consistent with the existing guidelines, some alternative therapeutic options were stressed, and the discussion contributed to bringing forth the issues that need further investigation. Hopefully, this comprehensive overview will improve the practice of iMCD and inform the design and implementation of new studies in the field.

The liver cancer immune microenvironment: Therapeutic implications for hepatocellular carcinoma

The liver is the sixth most common site of primary cancer in humans and the fourth leading cause of cancer-related death in the world. Hepatocellular carcinoma (HCC) accounts for 90% of liver cancers. HCC is a prevalent disease with a progression that is modulated by the immune system. Half of the patients with HCC receive systemic therapies, traditionally sorafenib or lenvatinib, as a first-line therapy. In the last few years, immune-checkpoint inhibitors (ICIs) have revolutionized cancer therapy and have gained an increased interest in the treatment of HCC. In 2020, the combination of atezolizumab (anti-programmed death-ligand 1) and bevacizumab (anti-vascular endothelial growth factor) improved overall survival over sorafenib, resulting in Food and Drug Administration (FDA) approval as a first-line treatment for patients with advanced HCC. Despite these major advances, a better molecular and cellular characterization of the tumor microenvironment is still needed because it has a crucial role in the development and progression of HCC. Inflamed (hot) and noninflamed (cold) HCC tumors and genomic signatures have been associated with response to ICIs. However, there are no additional biomarkers to guide clinical decision-making. Other immune-targeting strategies, such as adoptive T-cell transfer, vaccination, and virotherapy, are currently under development. This review provides an overview on the HCC immune microenvironment, different cellular players, current available immunotherapies, and potential immunotherapy modalities.

The diverse landscape of dermatologic toxicities of non-immune checkpoint inhibitor monoclonal antibody-based cancer therapy

BACKGROUND

Since their first approval 25 years ago, monoclonal antibodies (mAbs) have become important targeted cancer therapeutics. However, dermatologic toxicities associated with non-immune checkpoint inhibitor (non-ICI) mAbs may complicate the course of cancer treatment. Data on the incidence and types of these reactions are limited.

METHODS

A comprehensive review was conducted on dermatologic toxicities associated with different classes of non-ICI mAbs approved for treatment of solid tumors and hematologic malignancies. The review included prospective Phase 1, 2, and 3 clinical trials; retrospective literature reviews; systematic reviews/meta-analyses; and case series/reports.

RESULTS

Dermatologic toxicities were associated with several types of non-ICI mAbs. Inflammatory reactions were the most common dermatologic toxicities, manifesting as maculopapular, urticarial, papulopustular/acneiform, and lichenoid/interface cutaneous adverse events (cAEs) with non-ICI mAbs. Immunobullous reactions were rare and a subset of non-ICI mAbs were associated with the development of vitiligo cAEs.

CONCLUSION

Dermatologic toxicities of non-ICI mAbs are diverse and mostly limited to inflammatory reactions. Awareness of the spectrum of the histopathologic patterns of cAE from non-ICI mAbs therapy is critical in the era of oncodermatology and oncodermatopathology.

Approche thérapeutique des maladies de Castleman : l’émergence des thérapies ciblées

The spectrum of Castleman disease encompasses several different disorders. Nowadays three different forms of the disease are individualized: unicentric Castleman disease, multicentric HHV-8 associated Castleman disease and idiopathic multicentric Castleman disease. In the latter a severe form called TAFRO syndrome (thrombocytopenia, anasarca, myelofibrosis, renal dysfunction, and organomegaly) tend to be individualized. Improvement in the classification and understanding of the physiopathology of CD have allowed improvement in treatment strategies. Treatment of rare but often severe manifestations, such as paraneoplastic pemphigus and bronchiolitis obliterans in unicentric CD and hemophagocytic syndrome and/or Kaposi' sarcoma in HHV8 associated CD, are better adapted. Most of current treatment strategies are based on retrospective and very few prospective studies. Both anti-IL6/6R and anti-CD20 biotherapies have greatly improved the management of certain forms of the disease. We report in this review the most relevant studies and national or international expert consensus statements for the treatment in the different types of CD. © 2022 Published by Elsevier Masson SAS on behalf of Société nationale française de médecine interne (SNFMI).

Role of SARS-CoV-2-induced Cytokine Storm in Multi-Organ Failure: Molecular Pathways and Potential Therapeutic Options

Coronavirus disease 2019 (COVID-19) outbreak has become a global public health emergency and has led to devastating results. Mounting evidence proposes that the disease causes severe pulmonary involvement and influences different organs, leading to a critical situation named multi-organ failure. It is yet to be fully clarified how the disease becomes so deadly in some patients. However, it is proven that a condition called “cytokine storm” is involved in the deterioration of COVID-19. Although beneficial, sustained production of cytokines and overabundance of inflammatory mediators causing cytokine storm can lead to collateral vital organ damages. Furthermore, cytokine storm can cause post-COVID-19 syndrome (PCS), an important cause of morbidity after the acute phase of COVID-19. Herein, we aim to explain the possible pathophysiology mechanisms involved in COVID-19-related cytokine storm and its association with multi-organ failure and PCS. We also discuss the latest advances in finding the potential therapeutic targets to control cytokine storm wishing to answer unmet clinical demands for treatment of COVID-19.

Senescence and the tumor-immune landscape: Implications for cancer immunotherapy

Cancer therapies, including conventional chemotherapy, radiation, and molecularly targeted agents, can lead to tumor eradication through a variety of mechanisms. In addition to their effects on tumor cell growth and survival, these regimens can also influence the surrounding tumor-immune microenvironment in ways that ultimately impact therapy responses. A unique biological outcome of cancer therapy is induction of cellular senescence. Senescence is a damage-induced stress program that leads to both the durable arrest of tumor cells and remodeling the tumor-immune microenvironment through activation of a collection pleiotropic cytokines, chemokines, growth factors, and proteinases known as the senescence-associated secretory phenotype (SASP). Depending on the cancer context and the mechanism of action of the therapy, the SASP produced following therapy-induced senescence (TIS) can promote anti-tumor immunity that enhances therapeutic efficacy, or alternatively chronic inflammation that leads to therapy failure and tumor relapse. Thus, a deeper understanding of the mechanisms regulating the SASP and components necessary for robust anti-tumor immune surveillance in different cancer and therapy contexts are key to harnessing senescence for tumor control. Here we draw a roadmap to modulate TIS and its immune-stimulating features for cancer immunotherapy.

Glucocorticoids combined with tofacitinib in the treatment of Castleman's disease: A case report

BACKGROUND

Castleman's disease (CD), also known as vascular follicular lymphadenopathy is a rare proliferative disease of lymphoid tissue of unknown etiology that is clinically classified as unicentric CD (UCD) or multicentric CD (MCD) depending on lymph node involvement. At present, idiopathic MCD (iMCD) is treated with interleukin-6 inhibitors, but some patients have poor clinical outcomes. This paper reports on a case of iMCD that achieved a good therapeutic effect after treatment with glucocorticoids combined with tofacitinib. The relevant data are summarized and reported below.

CASE SUMMARY

This paper reports on a case of MCD in a 49-year-old female with persistent peritoneal effusion as the first manifestation and combined with multiple lymphadenopathies. Lymph node biopsy showed Castleman's disease-like changes. The ascites subsided after treatment with glucocorticoids and tofacitinib, indicating that the treatment was effective.

CONCLUSION

The combination of glucocorticoids with tofacitinib is an effective regimen for the treatment of CD.

Immune-related adverse events of biological immunotherapies used in COVID-19

The use of biological immunotherapeutic drugs is one of the options currently being evaluated and employed to manage COVID-19, specifically monoclonal antibodies, which have shown benefit by regulating the excessive immune response seen in patients with severe infection, known as a cytokine storm. Tocilizumab has received particular importance for this clinical application, as has sarilumab. Both drugs share a substantial similarity in terms of pharmacodynamics, being inhibitors of the interleukin six receptor (IL-6Rα). Furthermore, sotrovimab, a neutralizing anti-SARS CoV-2 antibody, has gained the attention of the scientific community since it has recently been authorized under certain circumstances, positioning itself as a new therapeutic alternative in development. However, despite their clinical benefit, biological immunotherapies have the potential to generate life-threatening immune-related adverse events. Therefore it is essential to review their incidence, mechanism, and risk factors. This review aims to provide a comprehensive understanding of the safety of the biological immunotherapeutic drugs currently recommended for the treatment of COVID-19, provide a review of the known immune-mediated adverse events and explore the potential immune-related mechanisms of other adverse reactions.

Siltuximab is associated with improved progression-free survival in idiopathic multicentric Castleman disease

Idiopathic multicentric Castleman disease (iMCD) is a rare, heterogeneous disorder involving multicentric lymphadenopathy, systemic inflammation, and cytokine-driven organ dysfunction. Despite the approval of siltuximab-a monoclonal antibody against interleukin-6-for the treatment of iMCD, it is not known how long patients should receive siltuximab before determining whether the treatment is beneficial and should be continued. We performed post hoc analyses of the phase 2 randomized, double-blind, placebo-controlled trial of siltuximab for the treatment of patients with iMCD (NCT01024036) to determine the sequence of normalization of laboratory, clinical, and lymph node responses in patients who responded to siltuximab. Seventy-nine patients were enrolled in the trial (n=53 siltuximab; n=26 placebo plus best supportive care). Progression-free survival (PFS) was significantly improved in siltuximab-treated patients compared with placebo (P=0.0001). The median PFS was 14.5 months (95% CI, 13.6-upper bound not reached) for patients on placebo, but not reached for patients on siltuximab. In siltuximab-treated patients who achieved a durable tumor (radiologic) and symptomatic response (18/53 [34%]), the median time to normalization of abnormal laboratory tests and clinical endpoints occurred in the following sequence: thrombocytosis, symptomatic response, elevated C-reactive protein, hypoalbuminemia, anemia, lymph node response, hyperfibrinogenemia, and elevated immunoglobulin G. Siltuximab treatment prolongs PFS, rapidly improves symptomatology, and provides meaningful clinical benefit despite some laboratory tests and enlarged lymph nodes taking months to normalize in treatment responders. These data support the continued front-line use of siltuximab for iMCD, as recommended by international guidelines.

Efficacy and Safety of Regimens Used for the Treatment of Multicentric Castleman Disease: A Systematic Review

OBJECTIVES

Treatment options for multicentric Castleman disease (MCD) remain limited. The only FDA-approved drug is siltuximab for idiopathic MCD (iMCD), but the response rate with siltuximab is less than 50%. We performed a systematic review to examine the efficacy and safety of various regimens used for the treatment of MCD.

METHODS

A database search on PubMed, Embase, Cochrane, Web of Science, and Clinicaltrials.gov using the terms "Castleman disease," "treatment outcome" and "patient safety" was done.

RESULTS AND CONCLUSIONS

Results from a randomized controlled trial (RCT) and an extension study highlighted the efficacy and long-term safety of siltuximab for iMCD; other trials showed tocilizumab to be a suitable alternative. A recent trial reported high response rates with thalidomide in iMCD patients. Promising results were reported for bortezomib in relapsed/ refractory MCD. For human herpesvirus 8 (HHV-8) associated MCD, rituximab along with doxorubicin therapy followed by maintenance with zidovudine and valganciclovir is the most effective therapy. A single-arm trial has highlighted the potential role of tocilizumab in HHV-8 MCD. Data for these regimens are limited and mostly comprise non-randomized trials. Further research on emerging agents could have a major impact on the treatment of this rare disease.

Comprehensive analysis of 65 patients with Castleman disease in a single center in China

This study aimed to investigate the epidemiologic, clinical, pathological characteristics, and treatment of patients with Castleman disease (CD) in a single center in China. We retrospectively analyzed the data of 65 Chinese CD patients, divided into unicentric CD (UCD) and multicentric CD (MCD) groups, and also microscopic subtypes as hypervascular (HV), plasmacytic (PC) and Mixed. Based on whether HHV-8 infection existed, MCD was subdivided into HHV-8-associated MCD and idiopathic Castleman disease (iMCD). Detailed epidemiologic, clinicopathological, and treatment data were analyzed and discussed. Of total 65 patients (UCD 33, MCD 32), HV (81.8%) accounted for the most of UCD and total. More females in UCD (60.6%) and more males in MCD (65.6%) were observed. CD occurred in all age groups, most commonly in 40-49 years. The mean age of onset of total was 38.5 years with PC higher than HV (45.5 vs. 35.1 years, P = 0.0413). The median diagnosis delay of MCD was longer than that of UCD (3.00 vs. 1.25 months, P = 0.0436). Abdomen (39.4%) and neck (30.3%) were the most-seen locations of lymphadenopathy in UCD, with neck (65.6%) being predominant in MCD. Mean major diameter of specimens of UCD was greater than MCD (6.4 vs. 3.1 cm, P < 0.0001). These results provided the featured and detailed profile of Castleman disease in Henan province in China with a considerable number of cases, which presented distinct evidence with other studies.

Treatment and Outcome of Castleman Disease: A Retrospective Report of 31 Patients

Background

Castleman disease (CD) is a rare and heterogeneous lymphoproliferative disorder with a spectrum of characteristic pathological abnormalities of lymph node. Furthermore, its clinical diagnosis is very challenging until pathological results are available. This study aimed to investigate the clinical presentations, treatment and prognosis of CD, thereby improving the understanding and diagnosis of CD.

Methods

This study retrospectively analyzed the clinical data of 31 patients with CD admitted to the First Hospital Affiliated Hospital of Chongqing Medical University January 2013 to December 2020. The chi-square test and the Mann–Whitney rank sum test were employed to calculate between-group differences for categorical and quantitative data, respectively.

Results

Clinically, patients with unicentric CD (UCD) usually present with lymphadenopathy. However, the clinical presentation of patients with multicentric CD (MCD) ranged from mild lymphadenopathy with B-symptoms (5/8, 62.5%) to intense inflammation, vascular leak syndrome (3/8, 37.5%), hepatosplenomegaly (3/8, 37.5%), organ insufficiency (3/8, 37.5%), and even death (2/8, 25.0%). Compared with UCD patients, patients with MCD had significantly lower levels of hemoglobin (104 (90,129) vs 137 (120,149), p=0.018) and plasma albumin (31.5 (27.0,37.0) vs 45.0 (40.0,46.5), p=0.001), but IgG levels were significantly increased. Patients with UCD were mainly treated with surgical resection alone, with a five-year survival rate of 95.65%. When siltuximab is not an option, steroid plus rituximab-based chemotherapy and specific supportive care are common options for MCD. Except for 2 deaths, the remaining MCD patients have stable disease or partial remission.

Conclusion

CD describes a heterogeneous group of disorders characterized by morphologically benign lymphoid hyperplasia. Notably, patients with MCD present varying degrees of inflammation responses, even involving multiple systems. Surgery is a direct and effective way to diagnose and treat UCD. In the absence of IL-6 antagonists, anti-inflammatory and immunosuppressive therapeutic strategies, and cytotoxic clearance of cells responsible for hypercytokinemia could be adopted.

Novel somatic alterations in unicentric and idiopathic multicentric Castleman disease

OBJECTIVES

Castleman disease (CD) is a heterogeneous group of disorders involving systemic inflammation and lymphoproliferation. Recently, clonal mutations have been identified in unicentric CD (UCD) and idiopathic multicentric CD (iMCD), suggesting a potential underlying neoplastic process.

METHODS

Patients with UCD or iMCD with next generation sequencing (NGS) data on tissue DNA and/or circulating tumor DNA (ctDNA) were included.

RESULTS

Five patients were included, 4 with iMCD and 1 with UCD. Four patients (80%) were women; median age was 40 years. Three of five patients (60%) had ≥1 clonal mutation detected on biopsy among the genes included in the panel. One patient with iMCD had a 14q32-1p35 rearrangement and a der(1)dup(1)(q42q21)del(1)(q42) (1q21 being IL-6R locus) on karyotype. This patient also had a NF1 K2459fs alteration on ctDNA (0.3%). Another patient with iMCD had a KDM5C Q836* mutation, and one patient with UCD had a TNS3-ALK fusion but no ALK expression by immunohistochemistry.

CONCLUSIONS

We report 4 novel somatic alterations found in patients with UCD or iMCD. The 1q21 locus contains IL-6R, and duplication of this locus may increase IL-6 expression. These findings suggest that a clonal process may be responsible for the inflammatory phenotype in some patients with UCD and iMCD.

Cytokine storm associated coagulation complications in COVID-19 patients: Pathogenesis and Management

Introduction

SARS-CoV-2, the causative agent of COVID-19, attacks the immune system causing an exaggerated and uncontrolled release of pro-inflammatory mediators (cytokine storm). Recent studies propose an active role of coagulation disorders in disease progression. This hypercoagulability has been displayed by marked increase in D-dimer in hospitalized patients.

Areas Covered

This review summarizes the pathogenesis of SARS-CoV-2 infection, generation of cytokine storm, the interdependence between inflammation and coagulation, its consequences and the possible management options for coagulation complications like venous thromboembolism (VTE), microthrombosis, disseminated intravascular coagulation (DIC), and systemic and local coagulopathy. We searched PubMed, Scopus, and Google Scholar for relevant reports using COVID-19, cytokine storm, and coagulation as keywords.

Expert Opinion

A prophylactic dose of 5000–7500 units of low molecular weight heparin (LMWH) has been recommended for hospitalized COVID-19 patients in order to prevent VTE. Treatment dose of LMWH, based on disease severity, is being contemplated for patients showing a marked rise in levels of D-dimer due to possible pulmonary thrombi. Additionally, targeting PAR-1, thrombin, coagulation factor Xa and the complement system may be potentially useful in reducing SARS-CoV-2 infection induced lung injury, microvascular thrombosis, VTE and related outcomes like DIC and multi-organ failure.

Pharmacological mechanism of immunomodulatory agents for the treatment of severe cases of COVID-19 infection

OBJECTIVE

Coronavirus disease 2019 (COVID-19) is a world-wide pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, treatment of severe COVID-19 is far from clear. Therefore, it is urgent to develop an effective option for the treatment of patients with COVID-19. Most patients with severe COVID-19 exhibit markedly increased serum levels of pro-inflammatory cytokines, including interferon (IFN)-α, IFN-γ, and interleukin (IL)-1β. Immunotherapeutic strategies have an important role in the suppression of cytokine storm and respiratory failure in patients with COVID-19.

METHODS

A systematic search in the literature was performed in PubMed, Scopus, Embase, Cochrane Library, Web of Science, as well as Google Scholar preprint database using all available MeSH terms for Coronavirus, SARS-CoV-2, anti-rheumatoid agents, COVID-19, cytokine storm, immunotherapeutic drugs, IFN, interleukin, JAK/STAT inhibitors, MCP, MIP, TNF.

RESULTS

Here, we first review common complications of COVID-19 patients, particularly neurological symptoms. We next explain host immune responses against COVID-19 particles. Finally, we summarize the existing experimental and clinical immunotherapeutic strategies, particularly anti-rheumatoid agents and also plasma (with a high level of gamma globulin) therapy for severe COVID-19 patients. We discuss both their therapeutic effects and side effects that should be taken into consideration for their clinical application.

CONCLUSION

It is suggested that immunosuppressants, such as anti-rheumatoid drugs, could be considered as a potential approach for the treatment of cytokine storm in severe cases of COVID-19. One possible limitation of immunosuppressant therapy is their inhibitory effects on host anti-viral immune response. So, the appropriate timing of administration should be carefully considered.

Insufficient evidence exists to use histopathologic subtype to guide treatment of idiopathic multicentric Castleman disease

Idiopathic multicentric Castleman disease (iMCD) is a rare immunologic disorder characterized by systemic inflammation, multicentric lymphadenopathy, and organ dysfunction. Enlarged lymph nodes demonstrate a spectrum of characteristic but variable histopathologic features historically categorized into hyaline vascular (HV) (or hypervascular [HyperV] more recently), plasmacytic, or "mixed." Though the etiology is unknown, a pro-inflammatory cytokine storm, often involving interleukin-6 (IL-6), contributes to pathogenesis. Anti-IL-6 therapy with siltuximab is the only FDA- or EMA-approved treatment based on efficacy and safety in multiple studies. Importantly, no patients considered to have HV histopathology achieved the primary endpoint in the Phase II study. NCCN currently recommends siltuximab first-line for iMCD, except for patients considered to have HV histopathology. We investigated whether histopathologic subtype should guide siltuximab treatment decisions. Secondary analyses of clinical trial and real-world data revealed similar clinical benefit across histopathologic subtypes. Notably, only 18 of 79 patients in the Phase II study were consistently classified into histopathologic subtype by three independent review panels, demonstrating limited reliability to guide treatment decisions. Real-world data further demonstrate siltuximab's effectiveness in patients considered to have HV (or HyperV). Though histopathology is a critical component for diagnosis, there is insufficient evidence to guide treatment based solely on lymph node histopathologic subtype.

Chimeric antigen receptor T cell therapy and nephrotoxicity: From diagnosis to treatment strategies

Chimeric antigen receptor T (CAR-T) cell therapy is a breakthrough in cancer treatment. With the widespread use of this therapy, increasing evidence is available that CAR-T cell therapy is associated with acute kidney injury (AKI). Nephrologists need to understand the potential nephrotoxicity arising from CAR-T cell therapy. Determining the cause of AKI is a key factor of clinical management. This review focuses on the clinical use of CAR-T cell therapy and the cause and outcomes of nephrotoxicity with its use. We also provide clinical suggestions for clinicians towards both better diagnosis and management of AKI in those receiving CAR-T cell therapy.

A Review on Currently Available Potential Therapeutic Options for COVID-19

A series of unexplained pneumonia cases currently were first reported in December 2019 in Wuhan, China. Official names have been announced for the virus responsible, previously known as "2019 novel coronavirus" and the diseases it causes are, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease (COVID-19), respectively. Despite great efforts worldwide to control SARS-CoV-2, the spread of the virus has reached a pandemic. Infection prevention and control of this virus is the primary concern of public health officials and professionals. Currently, several therapeutic options for COVID-19 are proposed and vaccine development has been initiated for prevention purposes. In this review, we will discuss the most recent evidence about the current potential treatment options including anti-inflammatory drugs, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, nucleoside analogs, protease inhibitors, monoclonal antibodies, and convalescent plasma therapy. Some other agents such as vitamin D and melatonin, which were recommended as potential adjuvant treatments for COVID-19 infection are also presented. Moreover, the potential use of convalescent plasma for treatment of COVID-19 infection was described. Furthermore, in the next part of the current review, various vaccination approaches against COVID-19 including whole virus vaccines, recombinant subunit vaccine, DNA vaccines, and mRNA vaccines are discussed.

Interleukin-6 in Rheumatoid Arthritis

The role of interleukin (IL)-6 in health and disease has been under a lot of scrutiny in recent years, particularly during the recent COVID-19 pandemic. The inflammatory pathways in which IL-6 is involved are also partly responsible of the development and progression of rheumatoid arthritis (RA), opening interesting perspectives in terms of therapy. Anti-IL-6 drugs are being used with variable degrees of success in other diseases and are being tested in RA. Results have been encouraging, particularly when anti-IL-6 has been used with other drugs, such as metothrexate (MTX). In this review we discuss the main immunologic aspects that make anti-IL-6 a good candidate in RA, but despite the main therapeutic options available to target IL-6, no gold standard treatment has been established so far.

Structural Understanding of Interleukin 6 Family Cytokine Signaling and Targeted Therapies: Focus on Interleukin 11

Cytokines are small signaling proteins that have central roles in inflammation and cell survival. In the half-century since the discovery of the first cytokines, the interferons, over fifty cytokines have been identified. Amongst these is interleukin (IL)-6, the first and prototypical member of the IL-6 family of cytokines, nearly all of which utilize the common signaling receptor, gp130. In the last decade, there have been numerous advances in our understanding of the structural mechanisms of IL-6 family signaling, particularly for IL-6 itself. However, our understanding of the detailed structural mechanisms underlying signaling by most IL-6 family members remains limited. With the emergence of new roles for IL-6 family cytokines in disease and, in particular, roles of IL-11 in cardiovascular disease, lung disease, and cancer, there is an emerging need to develop therapeutics that can progress to clinical use. Here we outline our current knowledge of the structural mechanism of signaling by the IL-6 family of cytokines. We discuss how this knowledge allows us to understand the mechanism of action of currently available inhibitors targeting IL-6 family cytokine signaling, and most importantly how it allows for improved opportunities to pharmacologically disrupt cytokine signaling. We focus specifically on the need to develop and understand inhibitors that disrupt IL-11 signaling.

Afebrile Pneumonia in a Patient With Multicentric Castleman Disease on Siltuximab: Infection Without Fever on Anti-Interleukin-6 Therapy

Castleman disease is a lymphoproliferative disorder characterized by atypical lymph node hyperplasia and systemic symptoms; it can also affect the skin and blood counts. The condition is categorized by the extent of involvement (unicentric or multicentric) and the observed lymph node pathology (hyaline-vascular, plasma cell or mixed cellularity). Pathogenesis also has a role in the classification and treatment of multicentric Castleman disease; this variant can either be related to the presence of human herpesvirus-8 (HHV-8) infection or associated with POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal proteins and skin changes) syndrome, or idiopathic. The principal cytokine responsible for causing idiopathic multicentric Castleman disease (IMCD) is interleukin-6 (IL-6). Therefore, treatment with agents that bind to IL-6 (such as siltuximab) or block the IL-6 receptor (such as tocilizumab) has been used. We report a woman with IMCD who was successfully being treated with siltuximab; her cutaneous manifestations and systemic disease (lung and lymph nodes) improved within three months. However, nine months after starting siltuximab, she developed a worsening cough and new infiltrates in the right lung on positron emission tomography/computed tomography (PET/CT) scan; there were no other constitutional symptoms such as fever, night sweats or fatigue. Differential diagnosis included Castleman disease recurrence, lung neoplasm and infection. Her pulmonary symptoms and infiltrates on scan resolved after treatment with systemic levofloxacin, indicating that she had an antibiotic-sensitive afebrile pneumonia. We postulate that her siltuximab therapy blocked the IL-6-associated fever and constitutional symptoms that normally are a hallmark of pneumonia. Therefore, patients who are receiving medications such as siltuximab and tocilizumab that block the IL-6 pathway and impair the acute phase inflammatory response may fail to manifest constitutional symptoms such as fever when infected.

Involvement of interleukin 6 in SARS-CoV-2 infection: siltuximab as a therapeutic option against COVID-19

The aim of the study was to explore the involvement of interleukin 6 in SARS-CoV-2 infection, and to position the drug siltuximab in the management of severe forms of COVID-19. A bibliographic search was performed in Pubmed on the immune response to the disease, and in ClinicalTrials.gov on clinical trials with interleukin 6 blockers. Interleukin 6 is involved in the cytokine cascade, which originates as a consequence of an excessive immune response secondary to viral infection, aggravating lung affectation. Blockers of this cytokine (tocilizumab, sarilumab and siltuximab) are being studied as a strategy for treating the disease. Siltuximab is a monoclonal antibody indicated in Castleman's disease that could be administered in a single dose of 11 mg/kg in severe forms of COVID-19 that have increased interleukin 6.

Repurposing Interleukin-6 Inhibitors to Combat COVID-19

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is a pandemic with major implications across the world. One of the most frequent causes of death from SARS-CoV-2 is fatal pneumonia from coronavirus disease 2019 (COVID-19), which is associated with the development of acute respiratory distress syndrome (ARDS). To date (as of April 2, 2020), other than supportive measures, there are no efficient therapeutic options for COVID-19-related ARDS, although the US Food and Drug Administration recently granted emergency authorization for the use of hydroxychoroquine/chloroquine for this indication (which is usually given with azithromycin). Although the pathogenesis for ARDS is under investigation, one of the major culprits is considered to be cytokine storm, especially from interleukin 6 (IL-6) release. Herein, we review potential use of IL-6 inhibitors, several of which are approved for other disease conditions, as potential novel treatment for the management of COVID-19-related ARDS.