Safety and efficacy of Rituximab in systemic sclerosis: A systematic review and meta-analysis

Advancing autoimmune Rheumatic disease treatment: CAR-T Cell Therapies - Evidence, Safety, and future directions

INTRODUCTION

Despite advancements in managing autoimmune rheumatic diseases (ARDs) with existing treatments, many patients still encounter challenges such as inadequate responses, difficulty in maintaining remission, and side effects. Chimeric Antigen Receptor (CAR) T-cell therapy, originally developed for cancer, has now emerged as a promising option for cases of refractory ARDs.

METHODS

A search of the literature was conducted to compose a narrative review exploring the current evidence, potential safety, limitations, potential modifications, and future directions of CAR-T cells in ARDs.

RESULTS

CAR-T cell therapy has been administered to patients with refractory ARDs, including systemic lupus erythematosus, antisynthetase syndrome, and systemic sclerosis, demonstrating significant improvement. Notable responses include enhanced clinical symptoms, reduced serum autoantibody titers, and sustained remissions in disease activity. Preclinical and in vitro studies using both animal and human samples also support the efficacy and elaborate on potential mechanisms of CAR-T cells against antineutrophil cytoplasmic antibody-associated vasculitis and rheumatoid arthritis. While cautious monitoring of adverse events, such as cytokine release syndrome, is crucial, the therapy appears to be highly tolerable. Nevertheless, challenges persist, including cost, durability due to potential CAR-T cell exhaustion, and manufacturing complexities, urging the development of innovative solutions to further enhance CAR-T cell therapy accessibility in ARDs.

CONCLUSIONS

CAR-T cell therapy for refractory ARDs has demonstrated high effectiveness. While no significant warning signs are currently reported, achieving a balance between therapeutic efficacy and safety is vital in adapting CAR-T cell therapy for ARDs. Moreover, there is significant potential for technological advancements to enhance the delivery of this treatment to patients, thereby ensuring safer and more effective disease control for patients.

The Use of "Acellbia"-A Biosimilar of Rituximab in Systemic Sclerosis

The possibilities of modern therapy for systemic sclerosis (SSc) remains limited, since most of the used drugs do not have a disease-modifying effect. This encourages the study of new approaches that potentially affect the fundamental pathological processes underlying the disease. One example is anti-B-cell therapy, in particular rituximab (RTX). Until now RTX does not have a registration for the treatment of SSc, but there is a large positive experience of its use, which is reflected in recent meta-analyses and clinical recommendations. Complicated and expensive methods for obtaining genetically engineered biological drugs (biologics) have contributed to the emergence of more accessible biosimilars, one of which is the RTX biosimilar, Acellbia (Biocad, Russian Federation). The ''biosimilar'' versions of RTX might reduce the cost of therapy and increase patients accessibility to this treatment option. The RTX biosimilar Acellbia (ACB) has received approval in Russian Federation in 2014 for all indications held by reference RTX (including rheumatoid arthritis and ANCA-associated vasculitis).

Safety and Tolerability of Rituximab in the Treatment of Systemic Sclerosis

Rituximab (RTX) has been used for the treatment of systemic sclerosis (SSс) for a long time and has shown good efficacy for skin fibrosis and interstitial lung disease (ILD). However, data on tolerability and long-term adverse events (AEs) during RTX therapy in SSc are insufficient. The objective of this study was to assess the tolerability and safety of RTX in patients with SSс in a long-term prospective follow-up. Our open-label prospective study included 151 SSс patients who received at least one RTX infusion. The mean age of the patients was 47.9 ± 13.4 years; the majority of them were women (83%). The mean disease duration was 6.4 ± 5.8 years. The mean follow-up period after the first RTX infusion was 5.6 ± 2.6 years (845.6 patient-years (PY)). All patients received RTX in addition to ongoing therapy with prednisone and/or immunosuppressants. AEs were assessed and recorded by a doctor in the hospital immediately after RTX infusion and then by patient's reported outcome during the observation period. All causes of death were considered, regardless of treatment. A total of 85 AEs (56%) were registered, the overall incidence of AEs was 10/100 PY (95% confidence interval (CI) 8-12). The highest frequency of all AEs was observed in the first 2-6 months after the first course of RTX, however, these were mainly mild and moderate AEs (71%). The most frequent AEs were infections, they were observed in 40% of cases, with no serious opportunistic infections reported. The overall incidence of all infections was 7.1/100 PY (95% CI 5.5-9), serious infections-1.5/100 PY (95% CI 0.9-2.6). Infusion reactions occurred in 8% of patients. Other AEs were noted in 3% (0.6/100 PY, 95% CI 0.3-1.4). The overall incidence of serious AEs was 18%-3.2/100 PY (95% CI 2.2-4.6). There was a significant decrease of the immunoglobulin G (Ig G) during follow-up; however, its average values remained within normal limits. There were 17 deaths (11%) (2/100 PY, 95% CI 1.3-3.2). In most cases, patients died from the progression of the major organ failure, which arose before RTX treatment. In our study, the safety profile of RTX in SSс was assessed as favorable. It was similar to the AE profile in other autoimmune diseases treated with RTX. With an increase in the cumulative dose of RTX, no increase in AEs was observed. The mortality is comparable to the other severe autoimmune diseases in observational studies. Monitoring of IgG may be useful for patients with SSс on RTX therapy for early detection of the risk of developing infectious complications. RTX could be considered as a relatively safe drug for the complex therapy of SSс when standard therapy is ineffective or impossible.

Efficacy of rituximab on disease activity, severity, and disease-related damage in patients with immunosuppressive-resistant systemic sclerosis

Background/aim

B-cell depletion with rituximab (RTX) is widely used as a rescue therapy in patients with systemic sclerosis (SSc). The aim herein was to analyze the progress of disease-related outcomes after RTX therapy in severe SSc patients.

Materials and methods

Included in this study were 27 SSc patients who were followed-up between 2012 and 2020 and received at least 1 cycle of RTX for active disease, despite receiving standard immunosuppressives (ISs). In addition to the European Scleroderma Study Group and European Scleroderma Trials and Research Group activity scores, Medsger's severity, and the recently developed Scleroderma Clinical Trials Consortium Damage Index values were evaluated initially and at 1 year after the first infusion. The progress of individual organ damage was also assessed at the end of the follow-up period (at least 6 months after the last infusion) using the data extracted from the medical records.

Results

Disease activity and severity-improved and disease-related overall damage worsened after the first year of RTX therapy (p < 0.001, p = 0.008, and p = 0.005). Some of the disease-related organ damage had improved at the end of the follow-up period, indicating its reversibility. Overall damage scores ≥11 after the first year of RTX therapy were found to be associated with mortality (p = 0.035).

Conclusion

RTX contributed to reducing the activity and severity in SSc patients with severe disease, nonetheless the efficacy related to the damage was limited. High damage scores in the first year were found to be associated with mortality. Spontaneous progress of manifestations requiring a longer period to improve and irregular consecutive RTX courses might lead to difficulties in differentiation between activity and damage.

Anti-topoisomerase 1 Antibody Level Changes after B Cell Depletion Therapy in Systemic Sclerosis

The aim of our study was to assess the relationship between the changes of antinuclear autoantibodies (ANAs) and autoantibodies to topoisomerase 1 (anti-Topo 1) in systemic sclerosis (SSs) patients on rituximab (RTX) therapy. The prospective study included 88 patients (73 women) with a mean age of 47 (17-71) years. The mean disease duration was 5.9 ± 4.8 years. The mean follow-up period was more than 2 years (27 (12-42) months). We documented a statistically significant change in skin score, the disease activity index, improvement of pulmonary function and reduction of mean dose of prednisolone after RTX treatment. There was a significant decrease in the number of patients with high levels of ANA and overall decrease of the ANA and anti-Topo 1 levels. A moderate positive statistically significant correlation was found between ANA and anti-Topo 1 (r = 0.403). In the group of patients positive for anti-Topo 1 there were a more pronounced depletion of B lymphocytes, significantly higher increase in forced vital capacity and diffusion capacity, decrease in the disease activity index, compared with patients negative for anti-Topo 1. We observed the decline in the level of ANA and anti-Topo 1 in SSc patients after RTX therapy, and it was correlated by an improvement of the main outcome parameters of the disease. Therefore, anti-Topo 1 positivity could be considered as a predictor of a better response to RTX treatment, especially in SSc patients with hyperproduction of anti-Topo 1.

Therapeutic Approaches to Systemic Sclerosis: Recent Approvals and Future Candidate Therapies

Systemic sclerosis is the rheumatic disease with the highest individual mortality. The severity of the disease is determined by the extent of fibrotic changes to cutaneous and internal organ tissues, the most life-threatening visceral manifestations being interstitial lung disease, SSc-associated-pulmonary arterial hypertension and myocardial involvement. The heterogeneity of the disease has initially hindered the design of successful clinical trials, but considerations on classification criteria have improved patient selection in trials, allowing the identification of more homogeneous groups of patients based on progressive visceral manifestations or the extent of skin involvement with a focus of patients with early disease. Two major subsets of systemic sclerosis are classically described: limited cutaneous systemic sclerosis characterized by distal skin fibrosis and the diffuse subset with distal and proximal skin thickening. Beyond this dichotomic subgrouping of systemic sclerosis, new phenotypic considerations based on antibody subtypes have provided a better understanding of the heterogeneity of the disease, anti-Scl70 antibodies being associated with progressive interstitial lung disease regardless of cutaneous involvement. Two targeted therapies, tocilizumab (a monoclonal antibody targeting interleukin-6 receptors (IL-6R)) and nintedanib (a tyrosine kinase inhibitor), have recently been approved by the American Food & Drug Administration to limit the decline of lung function in patients with SSc-associated interstitial lung disease, demonstrating that such better understanding of the disease pathogenesis with the identification of key targets can lead to therapeutic advances in the management of some visceral manifestations of the disease. This review will provide a brief overview of the pathogenesis of SSc and will present a selection of therapies recently approved or evaluated in this context. Therapies evaluated and approved in SSc-ILD will be emphasized and a review of recent phase II trials in diffuse cutaneous systemic sclerosis will be proposed. We will also discuss selected therapeutic pathways currently under investigation in systemic sclerosis that still lack clinical data in this context but that may show promising results in the future based on preclinical data.

Umbilical-Cord-Derived Mesenchymal Stromal Cells Modulate 26 Out of 41 T Cell Subsets from Systemic Sclerosis Patients

Systemic sclerosis (SSc) is an immune-mediated disease wherein T cells are particularly implicated, presenting a poor prognosis and limited therapeutic options. Thus, mesenchymal-stem/stromal-cell (MSC)-based therapies can be of great benefit to SSc patients given their immunomodulatory, anti-fibrotic, and pro-angiogenic potential, which is associated with low toxicity. In this study, peripheral blood mononuclear cells from healthy individuals (HC, n = 6) and SSc patients (n = 9) were co-cultured with MSCs in order to assess how MSCs affected the activation and polarization of 58 different T cell subsets, including Th1, Th17, and Treg. It was found that MSCs downregulated the activation of 26 out of the 41 T cell subsets identified within CD4⁺, CD8⁺, CD4⁺CD8⁺, CD4^-CD8^-, and γδ T cells in SSc patients (HC: 29/42) and affected the polarization of 13 out of 58 T cell subsets in SSc patients (HC: 22/64). Interestingly, SSc patients displayed some T cell subsets with an increased activation status and MSCs were able to downregulate all of them. This study provides a wide-ranging perspective of how MSCs affect T cells, including minor subsets. The ability to inhibit the activation and modulate the polarization of several T cell subsets, including those implicated in SSc's pathogenesis, further supports the potential of MSC-based therapies to regulate T cells in a disease whose onset/development may be due to immune system's malfunction.

Autoreactive B cell responses targeting nuclear antigens in systemic sclerosis: Implications for disease pathogenesis

A hallmark of disease pathogenesis of systemic sclerosis (SSc) is the presence of autoreactive B cell responses targeting nuclear proteins. Almost all SSc-patients harbour circulating antinuclear autoantibodies of which anti-topoisomerase 1, anti-centromere protein, anti-RNA polymerase III and anti-fibrillarin autoantibodies (ATA, ACA, ARA and AFA, respectively) are the most common and specific for SSc. In clinical practice, autoantibodies serve as diagnostic biomarkers and can aid in the identification of clinical phenotypes of the disease. However, factors driving disease progression in SSc are still poorly understood, and it is difficult to predict disease trajectories in individual patients. Moreover, treatment decisions remain rather empirical, with variable response rates in clinical trials due to patient heterogeneity. Current evidence has indicated that certain patients may benefit from B cell targeting therapies. Hence, it is important to understand the contribution of the antinuclear autoantibodies and their underlying B cell response to the disease pathogenesis of SSc.

Systemic sclerosis associated interstitial lung disease: a survey of current practices in France

Background

Interstitial lung disease (ILD) is the leading cause of mortality in systemic sclerosis (SSc).

Objective

We performed an overview of the diagnostic approaches, follow-up and treatment strategies used in France for the management of SSc-associated ILD (SSc-ILD).

Design Structured nationwide online surveyMethods

A structured nationwide online survey was submitted to participants via the French Medical Societies for Internal Medicine and Pneumology, and research groups on SSc-ILD from May 2018 to June 2020. The 79 multiple-choice and 9 open-ended questions covered the screening of ILD at baseline, monitoring of patients with established SSc-ILD and its management. Fourteen optional vignettes exploring different clinical phenotypes of SSc-ILD were submitted to evaluate therapeutic decisions.

Results

All of the 93 participants screened SSc patients for ILD at baseline with 83 (89%) participants relying on a systematic chest computed tomography (CT) scan. Pulmonary function tests (PFT) were prescribed by 87 (94%) participants at baseline and during follow-up. Treatment was started based on abnormal PFT (95%), chest CT scan characteristics (89%), worsening dyspnoea (72%) and drop in SpO₂ during 6-min walk tests (66%). First-line therapy was cyclophosphamide (CYC) (89%), mycophenolate mofetil (MMF) (83%) and prednisone (73%). Rituximab as second-line immunosuppressive therapy (41%) was preferred to antifibrotic agents (18%), and a median daily prednisone dose of 10 mg (interquartile range, 10-15) was prescribed by 73% participants. Extensive SSc-ILD with worsening PFT (95%), regardless of diffusing capacity for carbon monoxide values and skin extension, were more likely to be treated, and CYC was favoured over MMF (p < 0.01). Extensive SSc-ILD with disease duration of less than 5 years was also a criterium for treatment initiation.

Conclusion

This overview of practices in diagnosis, follow-up and treatment of SSc-ILD in France describes real-life management of patients. It highlights heterogeneity in this management and gaps in current strategies that should be addressed to improve and harmonize clinical practices in SSc-ILD.

Increased expression of the ectoenzyme CD38 in peripheral blood plasmablasts and plasma cells of patients with systemic sclerosis

Objective

CD38 is a type II glycoprotein highly expressed on plasmablasts and on short- and long-lived plasma cells, but weakly expressed by lymphoid, myeloid, and non-hematopoietic cells. CD38 is a target for therapies aimed at depleting antibody-producing plasma cells. Systemic sclerosis (SSc) is an immune-mediated disease with a well-documented pathogenic role of B cells. We therefore analyzed CD38 expression in different subsets of peripheral blood mononuclear cells (PBMCs) from a cohort of SSc patients.

Methods

Cell surface expression of CD38 was evaluated on PBMCs from SSc patients using eight-color flow cytometry analysis performed with a FacsCanto II (BD). Healthy individuals were used as controls (HC).

Results

Forty-six SSc patients (mean age 56, range 23-79 years; 38 females and 8 males), and thirty-two age- and sex-matched HC were studied. Twenty-eight patients had the limited cutaneous form and eighteen the diffuse cutaneous form of SSc. The mean disease duration was 7 years. Fourteen patients were on immunosuppressive therapy (14 MMF, 5 RTX). The total percentages of T, B and NK cells were not different between SSc and HC. Compared to HC, SSc patients had higher levels of CD3+CD38+ T cells (p<0.05), higher percentage (p<0.001) of CD3+CD4+CD25+FOXP3+ regulatory T cells, lower percentage (p<0.05) of CD3+CD56+ NK T cells. Moreover, SSc patients had higher levels of CD24^highCD19+CD38^high regulatory B cells than HC (p<0.01), while the amount of CD24+CD19+CD38+CD27+ memory B cells was lower (p<0.001). Finally, the percentages of circulating CD38^highCD27+ plasmablasts and CD138+CD38^high plasma cells were both higher in the SSc group than in HC (p<0.001). We did not observe any correlations between these immunophenotypes and disease subsets or duration, and ongoing immunosuppressive treatment.

Conclusions

The increased expression of CD38 in peripheral blood plasmablasts and plasma cells of SSc patients may suggest this ectoenzyme as a candidate therapeutic target, under the hypothesis that depletion of these cells may beneficially downregulate the chronic immune response in SSc patients. Validation of this data in multicenter cohorts shall be obtained prior to clinical trials with existing anti-CD38 drugs.

New Era in Systemic Sclerosis Treatment: Recently Approved Therapeutics

Systemic sclerosis (SSc) is a chronic autoimmune disease with a poor prognosis. Among the various complications of SSc, treatment options for the fibrotic lesions, skin sclerosis, and SSc-associated interstitial lung disease (SSc-ILD) have been limited. However, since 2019, the efficacy and safety of nintedanib, tocilizumab, and rituximab for SSc or SSc-ILD have been demonstrated in double-blind, randomized, placebo-controlled trials, respectively. The antifibrotic agent nintedanib was approved for SSc-ILD in all regions of the United States, Europe, and Japan after the SENSCIS study confirmed that it suppressed the reduction in forced vital capacity (FVC), a measure of SSc-ILD. Tocilizumab, an anti-interleukin-6 receptor antibody, was approved for the treatment of SSc-ILD in the United States after the FocuSSced study showed that it inhibited the decrease in FVC. Rituximab, an anti-CD20 antibody, showed improvement in both modified Rodnan skin score, a measure of skin sclerosis, and FVC in the DESIRES study, and was approved in Japan for the treatment of SSc itself. With the development of these three drugs, SSc treatment is entering a new era. This paper outlines the latest advances in SSc therapeutics, focusing on nintedanib, tocilizumab, and rituximab.

Pathogenetic Aspects of Systemic Sclerosis: A View Through the Prism of B Cells

Systemic sclerosis (SSc) is a rare fibrotic rheumatic disease, associated with psychological distress and increased morbidity and mortality due to skin involvement and internal organ damage. The current understanding of the complex pathogenesis is yet incomplete and disease therapeutic algorithms are far from optimal. Immunologic aberrations are considered key factors for the disease, along with vascular involvement and excess fibrosis. Adaptive immunity and its specialized responses are an attractive research target and both T and B cells have been extensively studied in recent years. In the present review, the focus is placed on B cells in SSc. B cell homeostasis is deranged and B cell subsets exhibit an activated phenotype and abnormal receptor signaling. Autoantibodies are a hallmark of the disease and the current perception of their diagnostic and pathogenetic role is analyzed. In addition, B cell cytokine release and its effect on immunity and fibrosis are examined, together with B cell tissue infiltration of the skin and lung. These data support the concept of targeting B cells as part of the therapeutic plan for SSc through well designed clinical trials.

Dysregulated B cell function and disease pathogenesis in systemic sclerosis

Systemic sclerosis (SSc) is a complex, immune-mediated rheumatic disease characterised by excessive extracellular matrix deposition in the skin and internal organs. B cell infiltration into lesional sites such as the alveolar interstitium and small blood vessels, alongside the production of defined clinically relevant autoantibodies indicates that B cells play a fundamental role in the pathogenesis and development of SSc. This is supported by B cell and fibroblast coculture experiments revealing that B cells directly enhance collagen and extracellular matrix synthesis in fibroblasts. In addition, B cells from SSc patients produce large amounts of profibrotic cytokines such as IL-6 and TGF-β, which interact with other immune and endothelial cells, promoting the profibrotic loop. Furthermore, total B cell counts are increased in SSc patients compared with healthy donors and specific differences can be found in the content of naïve, memory, transitional and regulatory B cell compartments. B cells from SSc patients also show differential expression of activation markers such as CD19 which may shape interactions with other immune mediators such as T follicular helper cells and dendritic cells. The key role of B cells in SSc is further supported by the therapeutic benefit of B cell depletion with rituximab in some patients. It is notable also that B cell signaling is impaired in SSc patients, and this could underpin the failure to induce tolerance in B cells as has been shown in murine models of scleroderma.

Efficacy and safety of biological drugs in interstitial lung disease associated with connective tissue diseases

INTRODUCTION

Interstitial lung disease (ILD) is one of the most important manifestations of connective tissue diseases (CTD) due to its association with high morbidity and mortality.

AREAS COVERED

Literature review focused on the evidence on efficacy and safety of biological therapy.

EXPERT OPINION

Rituximab (RTX) is the most studied drug, though tocilizumab (TCZ) has methodologically more robust evidence, whereas abatacept (ABA) has only anecdotal reports. RTX studies suggest a clinically relevant effect on lung function and fibrosis in refractory to conventional treatment patients, with a good safety profile. Its multi-level efficacy in systemic sclerosis and the potentially more favorable response of anti-synthetase syndrome, especially when administered early in acute-onset or exacerbated ILD stand out over current standard of care, pending the availability of randomized controlled clinical trials. The significant and clinically meaningful benefit found in lung function and fibrosis with TCZ in faSScinate and focuSSced trials represents a change with respect to the usual practice, reinforcing the importance of treatment in early subclinical or clinical SSc-ILD patients with risk factors for ILD progression. This evidence has led to the inclusion of both RTX and TCZ in the expert-based therapeutic algorithms or recommendations for CTD-ILD management.

TFH cells in systemic sclerosis

Systemic sclerosis is an autoimmune disease characterized by excessive dermal fibrosis with progression to internal organs, vascular impairment and immune dysregulation evidenced by the infiltration of inflammatory cells in affected tissues and the production of auto antibodies. While the pathogenesis remains unclear, several data highlight that T and B cells deregulation is implicated in the disease pathogenesis. Over the last decade, aberrant responses of circulating T follicular helper cells, a subset of CD4 T cells which are able to localise predominantly in the B cell follicles through a high level of chemokine receptor CXCR5 expression are described in pathogenesis of several autoimmune diseases and chronic graft-versus-host-disease. In the present review, we summarized the observed alteration of number and frequency of circulating T follicular helper cells in systemic sclerosis. We described their role in aberrant B cell activation and differentiation though interleukine-21 secretion. We also clarified T follicular helper-like cells involvement in fibrogenesis in both human and mouse model. Finally, because T follicular helper cells are involved in both fibrosis and autoimmune abnormalities in systemic sclerosis patients, we presented the different strategies could be used to target T follicular helper cells in systemic sclerosis, the therapeutic trials currently being carried out and the future perspectives from other auto-immune diseases and graft-versus-host-disease models.

B cell depletion inhibits fibrosis via suppressing pro-fibrotic macrophage differentiation in a mouse model of systemic sclerosis

OBJECTIVE

We investigated the effect of B cell depletion on fibrosis in systemic sclerosis (SSc) and its mechanism of action.

METHODS

Bleomycin-induced SSc (BLM-SSc) model mice were treated with anti-CD20 antibody, and skin and lung fibrosis was evaluated histopathologically. T cells and macrophages were co-cultured with B cells, and the effect of B cells on their differentiation was assessed by flow cytometry. We also co-cultured B cells and monocytes from SSc patients and analyzed the correlation between fibrosis and pro-fibrotic macrophage induction by B cells.

RESULTS

B cell depletion inhibited fibrosis in BLM-SSc mice. B cells from BLM-SSc mice increased pro-inflammatory cytokine producing T cells in co-culture. In BLM-SSc mice, B cell depletion before BLM treatment (pre-depletion) inhibited fibrosis more strongly than B cell depletion after BLM treatment (post-depletion). However, the frequencies of pro-inflammatory T cells were lower in the post-depletion group than in the pre-depletion group. This discrepancy suggests that the effect of B cell depletion on fibrosis cannot be explained by its effect on T cell differentiation. On the other hand, pro-fibrotic macrophages were markedly decreased in the pre-depletion group than in the post-depletion group. Furthermore, B cells from BLM-SSc mice increased pro-fibrotic macrophage differentiation in co-culture. In SSc patients, the extent of pro-fibrotic macrophage induction by B cells correlated with the severity of fibrosis.

CONCLUSION

These findings suggest that B cell depletion inhibits tissue fibrosis via suppressing pro-fibrotic macrophage differentiation in BLM-SSc mice, providing a new rationale for B cell depletion therapy in SSc.

Treatment for systemic sclerosis-associated interstitial lung disease

PURPOSE OF REVIEW

This review provides an overview of the current treatments for systemic sclerosis-interstitial lung disease (SSc-ILD) and proposes a conceptual framework for disease management with case scenarios.

RECENT FINDINGS

Broad treatment categories include traditional cytotoxic therapies, biologic disease-modifying rheumatic drugs, antifibrotic agents, autologous hematopoietic stem cell transplant, and lung transplantation. The optimal use of each option varies depending on SSc-ILD severity, progression, and comorbidities of individual patients. A high-quality randomized controlled trial demonstrated nintedanib's ability to retard decline of lung function in patients with limited and diffuse cutaneous disease, with established ILD. Tocilizumab, recently approved by the FDA, provides a unique intervention in those with early SSc associated with ILD with elevated acute-phase reactants: two well designed trials showed lung function preservation in phase 2 and phase 3 trials.

SUMMARY

Stratifying patients based on key SSc-ILD characteristics (e.g. severity, risk of progression, comorbid disease presentation) may provide a useful guide for practitioners treating SSc-ILD.

Efficacy and safety of rituximab therapy in patients with systemic sclerosis disease (SSc): systematic review and meta-analysis

The clinical benefits of rituximab in systemic sclerosis (SSc) are still contentious. The present meta-analysis aimed to systematically assess rituximab's safety and efficacy profile in SSc patients. A systematic online query was performed in PubMed, Scopus, Web of Science, and Embase. The studies on the application of rituximab for patients with SSc were reviewed comprehensively for over two years. In terms of efficacy profile, mRSS, MS, LVEF, sPAP, FVC, DLCO, TLC, FEV, DAS, severity activity, HAQ-DI and SF36 were assessed for organ involvement and quality of life. The level of biological and immunological markers was also evaluated in SSc patients treated with RTX. In total, 24 studies met the criteria. Although they did not have a high quality, they were free from heterogeneity and publication bias. The pooled results revealed a long-term improvement in mRSS and MS. HAQ-DI was improved to 0.78 after 12 months, and DAS was significantly reduced to 0.33, 0.23, and 0.24 following 6, 12, and 24 months of treatment, respectively (p = 0.00 for both parameters). The rest of the parameters remained stable over time in patients with SSc. The pooled analysis of these patients demonstrated that the induction of death, cancer, infection, and infusion were 9, 5, 18 and 10%, respectively. Based on the pooled results of this meta-analysis, rituximab improves skin score and disease indices and stabilizes organ involvement in SSc patients. Rituximab seems to possess reasonable safety, similar to previous data from other autoimmune diseases.

The clinical efficacy of Rituximab administration in autoimmunity disorders, primary immunodeficiency diseases and malignancies

Rituximab (RTX), as a monoclonal antibody-based immunotherapeutic intervention targeting CD20 on B cells, has proven efficacy in the treatment of patients with some immune-mediated diseases. In the present review, we provided information on the immunobiological mechanisms of signaling for RTX and its clinical applications, according to the immune-pathophysiology involved in the microenvironment of multiple diseases. We highlighted combination therapy, dose schedules, and laboratory monitoring, as well as the associated common and rare side effects to avoid. We also discussed the efficacy and safety of RTX-based therapeutic strategies and whether RTX therapy can be used as a promising treatment regimen for autoimmune diseases, primary immunodeficiency diseases, and malignancies. Our review highlights and supports the importance of collaboration between basic medical researchers and clinical specialists when considering the use of RTX in the treatment of various immune-mediated disorders.

B cells in systemic sclerosis: from pathophysiology to treatment

Systemic sclerosis is a debilitating autoimmune disease with unknown pathogenesis. The clinical phenotype of fibrosis is preceded by vascular and immunologic aberrations. Adaptive immunity has been extensively studied in patients with the disease and B cells appear to be dysregulated. This is evident in peripheral blood B cell subsets, with activated effector B cells and impaired B regulatory function. In addition, B cells infiltrate target organs and tissues of patients with the disease, such as the skin and the lung, indicating a probable role in the pathogenesis. Impaired B cell homeostasis explains the rationale behind B cell therapeutic targeting. Indeed, several studies in recent years have shown that depletion of B cells appears to be a promising treatment alongside current established therapeutic choices, such as mycophenolate. In this review, B cell aberrations in animal models and human patients with systemic sclerosis will be presented. Moreover, we will also summarize current existing data regarding therapeutic targeting of the B cells in systemic sclerosis.

Is rituximab effective for systemic sclerosis? A systematic review and meta-analysis

BACKGROUND

Systemic sclerosis (SSc) is a clinically complex and challenging disease, that leads to skin fibrosis. Its most frequent complication is interstitial lung disease (ILD), which leads to a worse prognosis. In this situation, cyclophosphamide is considered the gold standard for its treatment, despite the controversies regarding its efficacy and toxicity. However, studies using rituximab (RTX) have shown that this drug may be a promising therapeutic option.

OBJECTIVES

This paper objective was to analyze the scientific evidence on the RTX effects on SSc.

METHODS

A systematic review (SR) was performed including clinical trials (CTs) on the use of RTX in SSc, published up to May 2020. The studies were identified through systematic searches in bibliographic databases using a predefined search strategy. The following databases were used: PUBMED, SCOPUS, SCIELO, LILACS, SCIENCE DIRECT, WEB OF SCIENCE, COCHRANE, WHOLIS, PAHO and EMBASE. Also, a manual search was performed. The methodological quality of the studies was determined using Jadad scale, Risk of Bias Tool (RoB 2.0) and Risk of Bias in Non-Randomized Studies - of Interventions tool (ROBINS-I). A meta-analysis of the randomized CTs was performed, using Review Manager.

RESULTS

Ten CTs were included in this SR. Of these, three were randomized and seven were non-randomized. Five showed a statistically significant improvement in forced vital capacity (FVC) at some time during follow-up. Regarding the skin, eight studies showed statistically significant improvements according toa the modified Rodnan skin score. The meta-analysis found positive effects of RTX in SSc, with a statistical significance for lung disease.

CONCLUSION

Rituximab is a promising strategy for the SSc-associated ILD and cutaneous fibrosis treatment. PROSPERO registration number: CRD42019132018.

Efficacy and safety of rituximab on lung and skin involvement in systemic sclerosis: a systematic review and metaanalysis

OBJECTIVE

To evaluate the efficacy and safety of rituximab (RTX), an antiB cell monoclonal antibody, on lung and skin involvement in systemic sclerosis (SSc).

METHODS

All literature published in Embase and Medline before September 2019 were comprehensively searched. Two independent reviewers selected eligible studies, extracted relevant data, and assessed the quality of the included studies. We only considered randomized, controlled trials (RCTs), cohort studies, and case-control studies that compared RTX with a placebo, other immunosuppressive agents, or corticosteroids. All analyses were performed using RevMan (version 5.3).

RESULTS

A total of 8 studies (3 RCTs and 5 cohort studies) met our inclusion criteria. The pooled analysis showed a significant improvement of modified Rodnan skin score in the RTX group only in the cohort studies (mean difference [SD] - 3.31 [- 4.95, - 1.68]; I² = 82%). As to the PFT, the RTX group showed a significant improvement in the forced vital capacity only in 3 RCTs (mean difference [SD] 6.59 [3.51, 9.68]; I² = 0%). Additionally, the RTX group demonstrated a statistically significant improvement in the diffuse capacity of carbon monoxide only in the cohort studies (mean difference [SD] 7.42 [1.08, 13.76]; I² = 97%). There were no significant differences in the AEs of the RTX and control groups.

CONCLUSIONS

RTX may be effective for lung and skin involvement in SSc, with no serious AEs. However, further studies with high quality and a large sample size are necessary to firmly establish the efficacy and safety of the use of RTX with SSc patients. Key Points • RTX may be an alternative treatment for cutaneous and pulmonary manifestations in patients with SSc with a favorable safety profile. • However, further studies with a high quality and large sample size are necessary to firmly establish its efficacy and safety.

Rituximab as a rescue treatment added on mycophenolate mofetil background therapy in progressive systemic sclerosis associated interstitial lung disease unresponsive to conventional immunosuppression

OBJECTIVE

To test whether the use of rituximab (RTX) is effective and safe as a rescue therapy add-on treatment to mycophenolate (MMF) in patients with progressive systemic sclerosis-associated interstitial lung disease (SSc-ILD) in whom conventional immunosuppressants (IS) have failed.

METHODS

Longitudinal retrospective observational study of a cohort of patients with SSc-ILD that started treatment with RTX due to ongoing lung function impairment despite treatment with glucocorticoids and IS (cyclophosphamide and/or MMF). All patients were treated with 2 or more cycles of RTX and evaluated for at least 12 months.

RESULTS

Twenty-four patients were included. Before initiation of RTX the mean decline in%pFVC and %pDLCO during the previous 2 years (delta) was -12.9% and -12.5%, respectively. After 1 year of treatment with RTX, a significant improvement in %pFVC (∆+8.8% compared to baseline, 95% CI: -13.7 to -3.9; p = 0.001) and%pDLCO (∆+4.6%, 95% CI: -8.2 to -0.8; p = 0.018) was observed. In addition, there was a significant reduction in the median dose of prednisone and it could be suspended in 25% of patients. At 2 years of treatment, RTX had been discontinued in 9 patients (due to adverse events in 3 cases and inefficacy in 6). In the 15 patients (62.5%) that completed 24 months of therapy, the statistically significant amelioration in pulmonary function test parameters was maintained: ∆%pFVC: +11.1% (95% CI: -17.6 to -4.5; p = 0.003) and ∆%pDLCO: +8.7% (95% CI: -13.9 to -8.3; p = 0.003).

CONCLUSION

Based on our results, RTX's use as an add-on treatment to MMF appears to be effective as a rescue therapy in patients with a more aggressive SSc-ILD phenotype.

Modern view on treatment of membranous nephropathy

Membranous nephropathy (MN) is the most common cause of nephrotic syndrome in adults. Since the moment of animal model creation and the recognition of podocytes damage as a key mechanism of MN development, the identification of antigens, first of all the phospholipase A2 receptor (PLA2R), and the development of methods of PLA2R autoantibodies detection and its monitoring opened a new era in the idiopathic MN (iMN) diagnosis, treatment and prognosis evaluation. MN continues to be actively studied in the new millennium, since a number of aspects of its pathogenesis still need to be clarified, and there is still no clear opinion on the iMN treatment optimal approach. Comprehensive clinical and serological assessment of patients with iMN can be the key to individual choice of treatment protocols. In patients with aPLA2R-positive iMN, the predictor of disease remission is the aPLA2R titer decrease or aPLA2R disappearance in the blood serum, and disease relapse is associated with the aPLA2R appearance ore increase of aPLA2R titer in the circulation. Studies which were conducted by today (GEMRITUX, MENTOR, STARMEN, NICE, etc.) confirmed the acceptable safety profile and effectiveness of iMN therapy by anti-CD20 monoclonal antibodies (rituximab): more than half of of iMN patients had remission of nephrotic syndrome or proteinuria decrease, remissions in anti-CD20 monoclonal antibodies treated patients were longer compared to traditional therapy. The obtained data allows us to consider rituximab and anti-CD20 antibody therapy of a new generation not only as an alternative to the more toxic treatment with cyclophosphane and calcineurin inhibitors, but as an independent promising direction of therapy for patients with IMN, which completely changes the paradigm of treatment of this glomerulopathy.