Rituximab Therapy for Primary Sjögren's Syndrome

Switching from rituximab originator to GP2013 or CT-P10 biosimilars in autoimmune rheumatic diseases: drug retention rate and safety data from a multicentric retrospective cohort

Background

Real-world evidence supporting a safe and effective transition from rituximab originator (RTX-O) to its biosimilars (RTX-B) in autoimmune rheumatic diseases (ARDs) is still limited.

Objectives

The primary aims of this study were to evaluate the long-term persistence of RTX-B after the non-medical switch (NMS) from RTX-O in ARD patients, and to explore the RTX-B safety profile. The secondary aims were to evaluate the impact of different factors on RTX-B drug retention rate (DRR) and to identify any factors associated with RTX-B discontinuation.

Design

Retrospective observational study.

Methods

We included consecutive ARD patients undergoing NMS from RTX-O to GP2013 or CT-P10 from January 2018 to December 2020. RTX-B DRR was estimated by Kaplan-Meier plot analysis and compared according to different factors by the Log-rank test; the Cox proportional hazard model was used to detect factors associated with RTX-B discontinuation in the first 36 months.

Results

We enrolled 181 patients switching to RTX-B: GP2013 in 143 (79.0%) cases and CT-P10 in 38 (21.0%). The estimated DRR for RTX-B was 81.5% at 12 months, 80.6% at 24 months, and 77.4% at 36 months. The incidence of adverse events with RTX-B was 12.6/100 patients/year. In the Log-rank test, no statistically significant differences were observed in the RTX-B DRR according to sex (p = 0.171), ARD diagnosis (p = 0.281), and concomitant immunosuppressive therapy (p = 0.054); on the contrary, patients on GP2013 showed a higher DRR than those on CT-P10 (p < 0.001). In the Cox proportional hazard analysis, the switch to CT-P10 was associated with a higher probability of stopping treatment (hazard ratio, 1.83 (confidence interval, 1.10-3.04), p = 0.02).

Conclusion

NMS to RTX-B is associated with a high chance of retaining the drug for up to 36 months, irrespective of the diagnosis. GP2013 showed a higher retention rate than CT-P10.

Novel and potential future therapeutic options in Sjögren's syndrome

Sjögren's syndrome (SS) is a chronic autoimmune disease affecting the exocrine glands and can lead to various systemic symptoms impacting multiple organs. Despite its common occurrence, treatment options for SS have been largely limited, primarily focusing on alleviating symptoms rather than addressing the underlying autoimmune causes. A shift towards personalized medicine leads to the development of new therapeutic strategies aimed at targeting specific molecular pathways implicated in SS. Innovations in biologics are paving the way for inhibiting particular cytokines or cell surface molecules directly involved in the autoimmune mechanism. Furthermore, advancements in regenerative medicine, including the promising field of stem cell therapy, offer the potential for restoring or replacing the impaired salivary and lacrimal glands, providing hope for a more permanent resolution to this condition. This review encompasses cutting-edge treatment strategies for SS, spanning clinical and preclinical drugs to the latest treatment technology. Such advancements promise to drive targeted therapy development and inspire innovative ideas for treatment paradigms in SS.

Subpopulation dynamics of T and B lymphocytes in Sjögren's syndrome: implications for disease activity and treatment

Sjögren's syndrome (SS) is an autoimmune disorder primarily affecting the body's exocrine glands, particularly the salivary and lacrimal glands, which lead to severe symptoms of dry eyes and mouth. The pathogenesis of SS involves the production of autoantibodies by activated immune cells, and secretion of multiple cytokines, which collectively lead to tissue damage and functional impairment. In SS, the Immune interaction among T and B cells is particularly significant. Lymphocytic infiltration in the salivary glands is predominantly composed of CD4+ T cells, whose activation cause the death of glandular epithelial cells and subsequent tissue destruction. The excessive activity of T cells contributes significantly to the disease mechanism, with helper T cells (CD4+) differentiating into various subgroups including Th1/Th2, Th17, as well as Treg, each contributing to the pathological process through distinct cytokine secretion. In patients with SS, B cells are excessively activated, leading to substantial production of autoantibodies. These antibodies can attack self-tissues, especially the lacrimal and salivary glands, causing inflammation and tissue damage. Changes in B cell subpopulations in SS patients, such as increases in plasmablasts and plasma cells, correlate positively with serum autoantibody levels and disease progression. Therapies targeting T cells and B cells are extensively researched with the aim of alleviating symptoms and improving the quality of life for patients. Understanding how these cells promote disease development through various mechanisms, and further identifying novel T and B cell subgroups with functional characterization, will facilitate the development of more effective strategies to treat SS.

Primary Sjogren syndrome - A bibliometric analysis via CiteSpace

This study employs CiteSpace software to analyze the research status, hotspots, and trends of primary Sjogren syndrome (pSS). Relevant publications from 1999 to 2023 were searched in the Web of Science Core Collection (WoSCC) set, followed by generating a network map using CiteSpace software to identify top authors, institutions, countries, keywords, journals, references, and research trends. A total of 3564 valid articles were included in this study. The People Republic of China had the highest number of articles (n = 524), while the University of Bergen emerged as the institution with the highest publication count (n = 94). Mariette X was identified as the author with the most publications (n = 67), whereas Vitali C received recognition as the most cited author (n = 1706). Annals of Rheumatic Diseases stood out as the journal with the highest citation count (n = 2530). Notably, an article published in the Annals of Rheumatic Diseases in 2017 garnered significant attention by being cited a remarkable 304 times. The bibliometric analysis reveals that key areas of research in pSS encompass investigating pathogenesis; advancing and applying targeted biological agents; and establishing treatment and diagnostic standards.

Treatment of non-systemic Sjögren's syndrome: Potential prevention of systematization with immunosuppressant agent/biotherapy

Sjögren's syndrome (SS) is a systemic autoimmune pathology manifested mainly by a dry syndrome, intense asthenia and arthromyalgia. Systemic manifestations may also occur. Since 2019, immunosuppressant agents (IS) or biotherapies are recommended only for patients with systemic involvement. However, before 2019, in some cases, paucisymptomatic patients had been treated with IS/biotherapies, often off-label. Objective: We propose to evaluate the benefit and safety of using IS/biotherapy in patients with SS without systemic involvement. Methods: We retrospectively collected the clinical records of all patients with SS diagnosed according to ACR/EULAR diagnostic criteria followed up between January 1980 and October 2023 at Grenoble University Hospital (France). Results: Eighty-three patients were included: 64 with an initially non-systemic form. Of these patients with an initially non-systemic form, 24 were treated with IS/biotherapy. None of them developed secondary systematization, whereas 11 out of 40 patients in the untreated group did (p < 0.05). On the other hand, IS/biotherapy did not appear to improve dry syndrome. There were no serious adverse events. Conclusion: Early introduction of an IS/biotherapy treatment appears to provide a benefit for the patient without side effects.

Emerging biologic frontiers for Sjogren's syndrome: Unveiling novel approaches with emphasis on extra glandular pathology

Primary Sjögren's Syndrome (pSS) is a complex autoimmune disorder characterized by exocrine gland dysfunction, leading to dry eyes and mouth. Despite growing interest in biologic therapies for pSS, FDA approval has proven challenging due to trial complications. This review addresses the absence of a molecular-target-based approach to biologic therapy development and highlights novel research on drug targets and clinical trials. A literature search identified potential pSS treatment targets and recent advances in molecular understanding. Overlooking extraglandular symptoms like fatigue and depression is a notable gap in trials. Emerging biologic agents targeting cytokines, signal pathways, and immune responses have proven efficacy. These novel therapies could complement existing methods for symptom alleviation. Improved grading systems accounting for extraglandular symptoms are needed. The future of pSS treatment may involve gene, stem-cell, and tissue-engineering therapies. This narrative review offers insights into advancing pSS management through innovative biologic interventions.

B-Cell Receptor Repertoire: Recent Advances in Autoimmune Diseases

In the field of contemporary medicine, autoimmune diseases (AIDs) are a prevalent and debilitating group of illnesses. However, they present extensive and profound challenges in terms of etiology, pathogenesis, and treatment. A major reason for this is the elusive pathophysiological mechanisms driving disease onset. Increasing evidence suggests the indispensable role of B cells in the pathogenesis of autoimmune diseases. Interestingly, B-cell receptor (BCR) repertoires in autoimmune diseases display a distinct skewing that can provide insights into disease pathogenesis. Over the past few years, advances in high-throughput sequencing have provided powerful tools for analyzing B-cell repertoire to understand the mechanisms during the period of B-cell immune response. In this paper, we have provided an overview of the mechanisms and analytical methods for generating BCR repertoire diversity and summarize the latest research progress on BCR repertoire in autoimmune diseases, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), primary Sjögren's syndrome (pSS), multiple sclerosis (MS), and type 1 diabetes (T1D). Overall, B-cell repertoire analysis is a potent tool to understand the involvement of B cells in autoimmune diseases, facilitating the creation of innovative therapeutic strategies targeting specific B-cell clones or subsets.

B cell repopulation trajectory after rituximab treatment in autoimmune diseases: a longitudinal observational study

To investigate B-cell repopulation trajectory and the associated factors in patients with autoimmune diseases (AIDs) who underwent rituximab (RTX) treatment. This is a retrospective study in a large tertiary medical center. Kaplan-Meier analysis and Cox regression were used to investigate factors associated with B-cell repopulation. Latent class trajectory modeling (LCTM) was employed to identify distinct B-cell repopulation trajectory longitudinally. A total of 224 patients were included, with a cumulative follow-up time of 193.6 person-years. Patients with antineutrophil cytoplasm antibody-associated vasculitis (AAV), connective tissue disease, and IgG4-related disease exhibited significant differences in B-cell repopulation time (p = 0.0055 by log-rank test). Multivariate Cox regression identified that higher levels of IgA (HR 1.21, 95%CI 1.01-1.45, p = 0.040) and concurrent glucocorticoid use (HR = 0.37,95%CI 0.20-0.67, p = 0.001) were associated with B-cell repopulation. The cluster showing prolonged B-cell depletion, identified by LCTM, had lower proportions of male (27% vs. 48.5%, p = 0.033), smoke history (17.6% vs. 38.7%, p = 0.025), higher proportions of AAV (44.3% vs. 15.2%, p = 0.004), RTX dose (p = 0.042), history of cyclophosphamide use (70.4% vs. 48.5%, p = 0.003), meanwhile glucocorticoid use (94.8% vs. 72.7%, p = 0.001). The trajectory of B-cell repopulation after RTX infusion in AIDs was heterogeneous. Certain factors were associated with B-cell repopulation, and a specific cluster of patients demonstrated prolonged B-cell depletion after RTX treatment.

Emerging treatment for Sjögren's disease: a review of recent phase II and III trials

INTRODUCTION

Sjögren's Disease, SjD, is a systemic autoimmune disorder characterized by reduced function of the salivary and lacrimal glands. Patients suffer from dryness, fatigue, and pain and may present with or without extra-glandular organ involvement. Symptoms limit SjD patients' quality of life and are the most difficult to improve with therapy. SjD patients are heterogeneous and clustering them into biologically similar subgroups might improve the efficacy of therapies. The need for therapies that address both the symptoms and extra glandular organ involvement of SjD presents an unmet opportunity that has recently attracted a growing interest in the pharmaceutical industry.

AREAS COVERED

The goal of this report is to review recent phase II/III studies in SjD. To accomplish our goal, we performed a literature search for phase II/III studies and abstracts recently presented at conferences.

EXPERT OPINION

This review allows updates the reader on the multitude of recent phase II/III clinical trials. We speculate on how subtypes of SjD will drive future therapeutic targeting and inform pathogenesis.

Causal associations of Sjögren's syndrome with cancers: a two-sample Mendelian randomization study

BACKGROUND

Several observational studies have explored the associations between Sjögren's syndrome (SS) and certain cancers. Nevertheless, the causal relationships remain unclear. Mendelian randomization (MR) method was used to investigate the causality between SS and different types of cancers.

METHODS

We conducted the two-sample Mendelian randomization with the public genome-wide association studies (GWASs) summary statistics in European population to evaluate the causality between SS and nine types of cancers. The sample size varies from 1080 to 372,373. The inverse variance weighted (IVW) method was used to estimate the causal effects. A Bonferroni-corrected threshold of P < 0.0031 was considered significant, and P value between 0.0031 and 0.05 was considered to be suggestive of an association. Sensitivity analysis was performed to validate the causality. Moreover, additional analysis was used to assess the associations between SS and well-accepted risk factors of cancers.

RESULTS

After correcting the heterogeneity and horizontal pleiotropy, the results indicated that patients with SS were significantly associated with an increased risk of lymphomas (odds ratio [OR] = 1.0010, 95% confidence interval [CI]: 1.0005-1.0015, P = 0.0002) and reduced risks of prostate cancer (OR = 0.9972, 95% CI: 0.9960-0.9985, P = 2.45 × 10-5) and endometrial cancer (OR = 0.9414, 95% CI: 0.9158-0.9676, P = 1.65 × 10-5). Suggestive associations were found in liver and bile duct cancer (OR = 0.9999, 95% CI: 0.9997-1.0000, P = 0.0291) and cancer of urinary tract (OR = 0.9996, 95% CI: 0.9992-1.0000, P = 0.0281). No causal effect of SS on other cancer types was detected. Additional MR analysis indicated that causal effects between SS and cancers were not mediated by the well-accepted risk factors of cancers. No evidence of the causal relationship was observed for cancers on SS.

CONCLUSIONS

SS had significant causal relationships with lymphomas, prostate cancer, and endometrial cancer, and suggestive evidence of association was found in liver and bile duct cancer and cancer of urinary tract, indicating that SS may play a vital role in the incidence of these malignancies.

Severe Headache in Primary Sjögren's Syndrome Responded to Rituximab

Introduction

Primary Sjögren syndrome (pSS) is an immune systemic disease, that may affect the central nervous system. A severe headache unresponsive to treatment is the headache which is persistently nonresponsive to narcotic analgesics.

Case presentation

A 48-year-old woman with a 10-year history of pSS was seen in January 2021, complaining of a headache one week previously. The headache was characterised by a dull persistent pressing intensity and was not responding to paracetamol, NSAIDs or codeine. She had no previous history, nor family history. Physical examination revealed bilateral parotid glands enlargement. Laboratory tests showed anaemia, and elevated levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), with positive anti-La and anti-Ro antibodies. She was given topical treatment and different doses of Predlone, in addition to methotrexate10 mg/week. She had received three pulses of methylprednisolone and was started on azathioprine with a mild response to the headaches, so she received two initial IV doses of rituximab 375 mg/m2, then every 2 weeks, with a clinical and laboratory response. Two years later, she had no headache.

Discussion

Headache that may presented in pSS are tension headaches, migraines and cluster headaches. The therapy is disease-modifying antirheumatic drugs, hydroxychloroquine, glucocorticoids and biotherapeutics. Rituximab is used in the treatment of some patients with pSS, especially where it can affect systemic symptoms.

Conclusion

Rituximab treatment may be an option for severe headache in patients with pSS. The mechanism is unknown but may be due to depletion of brain auto-reactive B cells. Further research is needed.

LEARNING POINTS

An unresponsive headache in a patient with primary Sjögren's syndrome treated with tryptophan, opioids and NSAIDs responded successfully to B-cell depletion with rituximab.We hypothesise that brain-autoreactive B cells were involved in the pathogenesis of the headache.

Application of single-cell RNA sequencing methods to develop B cell targeted treatments for autoimmunity

The COVID-19 pandemic coincided with several transformative advances in single-cell analysis. These new methods along with decades of research and trials with antibody therapeutics and RNA based technologies allowed for highly effective vaccines and treatments to be produced at astonishing speeds. While these tools were initially focused on models of infection, they also show promise in an autoimmune setting. Self-reactive B cells play important roles as antigen-presenting cells and cytokine and autoantibody producers for many autoimmune diseases. Yet, current therapies to target autoreactive B cells deplete all B cells irrespective of their pathogenicity. Development of self-reactive B cell targeting therapies that would spare non-pathogenic B cells are needed to treat disease while allowing effective immune responses to other ailments. Single-cell RNA sequencing (scRNA-seq) approaches will aid in identification of the pathogenic self-reactive B cells operative in autoimmunity and help with development of more favorable precision targeted therapies.

Correlations between the histopathological alterations in minor salivary glands and the clinically suspected Sjögren's syndrome

In sicca syndrome patients the xerostomia, xerophthalmia and the serological findings may strongly suggest the autoimmune Sjögren's syndrome, but the histological findings in the labial salivary gland biopsies do not always justify the suspected diagnosis. The aim of this study was to compare the histomorphological changes and the clinical findings in patients with pathologically established Sjögren's syndrome and in cases with negative histology. A total of 133 labial biopsies have been retrospectively evaluated from 2015 to May 2022, and the characteristic Sjögren's lesions were found in 67 cases. According to the clinical data, 34 cases proved to be primary, and 33 were associated ("secondary") forms. In 66 cases, the histology did not justify Sjögren's syndrome; a significant acinar loss, fibrolipomatous infiltration, and mild sialadenitis had led to the clinical symptoms. In Sjögren's histologies, the acinar loss was detected in just 31.8% of cases, which might indicate that the diminished saliva production represents immune-mediated hypofunction rather than direct damage of the acini. This is the first systemic study in Hungary investigating the correlation between pathological alterations and clinical findings.

Heterogeneity of antibody-secreting cells infiltrating autoimmune tissues

The humoral response is frequently dysfunctioning in autoimmunity with a frequent rise in total serum immunoglobulins, among which are found autoantibodies that may be pathogenic by themselves and/or propagate the inflammatory reaction. The infiltration of autoimmune tissues by antibody-secreting cells (ASCs) constitutes another dysfunction. The known high dependency of ASCs on the microenvironment to survive combined to the high diversity of infiltrated tissues implies that ASCs must adapt. Some tissues even within a single clinical autoimmune entity are devoid of infiltration. The latter means that either the tissue is not permissive or ASCs fail to adapt. The origin of infiltrated ASCs is also variable. Indeed, ASCs may be commonly generated in the secondary lymphoid organ draining the autoimmune tissue, and home at the inflammation site under the guidance of specific chemokines. Alternatively, ASCs may be generated locally, when ectopic germinal centers are formed in the autoimmune tissue. Alloimmune tissues with the example of kidney transplantation will also be discussed own to their high similarity with autoimmune tissues. It should also be noted that antibody production is not the only function of ASCs, since cells with regulatory functions have also been described. This article will review all the phenotypic variations indicative of tissue adaptation described so for at the level of ASC-infiltrating auto/alloimmune tissues. The aim is to potentially define tissue-specific molecular targets in ASCs to improve the specificity of future autoimmune treatments.

Management of Sjogren's Dry Eye Disease-Advances in Ocular Drug Delivery Offering a New Hope

Sjögren's syndrome is a chronic and insidious autoimmune disease characterized by lymphocyte infiltration of exocrine glands. Patients typically present with dry eye, dry mouth, and other systemic manifestations. Currently, the available molecules and drug-delivery systems for the treatment of Sjögren's syndrome dry eye (SSDE) have limited efficacy since they are not specific to SSDE but to dry eye disease (DED) in general. The current treatment modalities are based on a trial-and-error approach using primarily topical agents. However, this approach gives time for the vicious cycle of DED to develop which eventually causes permanent damage to the lacrimal functional unit. Thus, there is a need for more individualized, specific, and effective treatment modalities for SSDE. The purpose of this article is to describe the current conventional SSDE treatment modalities and to expose new advances in ocular drug delivery for treating SSDE. A literature review of the pre-clinical and clinical studies published between 2016 and 2022 was conducted. Our current understanding of SSDE pathophysiology combined with advances in ocular drug delivery and novel therapeutics will allow the translation of innovative molecular therapeutics from the bench to the bedside.

The Future of Targeted Treatment of Primary Sjögren's Syndrome: A Focus on Extra-Glandular Pathology

Primary Sjögren's syndrome (pSS) is a chronic, systemic autoimmune disease defined by exocrine gland hypofunction resulting in dry eyes and dry mouth. Despite increasing interest in biological therapies for pSS, achieving FDA-approval has been challenging due to numerous complications in the trials. The current literature lacks insight into a molecular-target-based approach to the development of biological therapies. This review focuses on novel research in newly defined drug targets and the latest clinical trials for pSS treatment. A literature search was conducted on ClinicalTrials.gov using the search term "Primary Sjögren's syndrome". Articles published in English between 2000 and 2021 were included. Our findings revealed potential targets for pSS treatment in clinical trials and the most recent advances in understanding the molecular mechanisms underlying the pathogenesis of pSS. A prominent gap in current trials is in overlooking the treatment of extraglandular symptoms such as fatigue, depression, and anxiety, which are present in most patients with pSS. Based on dryness and these symptom-directed therapies, emerging biological agents targeting inflammatory cytokines, signal pathways, and immune reaction have been studied and their efficacy and safety have been proven. Novel therapies may complement existing non-pharmacological methods of alleviating symptoms of pSS. Better grading systems that add extraglandular symptoms to gauge disease activity and severity should be created. The future of pSS therapies may lie in gene, stem-cell, and tissue-engineering therapies.

Autoantibodies - enemies, and/or potential allies?

Autoantibodies are well known as potentially highly harmful antibodies which attack the host via binding to self-antigens, thus causing severe associated diseases and symptoms (e.g. autoimmune diseases). However, detection of autoantibodies to a range of disease-associated antigens has enabled their successful usage as important tools in disease diagnosis, prognosis and treatment. There are several advantages of using such autoantibodies. These include the capacity to measure their presence very early in disease development, their stability, which is often much better than their related antigen, and the capacity to use an array of such autoantibodies for enhanced diagnostics and to better predict prognosis. They may also possess capacity for utilization in therapy, in vivo. In this review both the positive and negative aspects of autoantibodies are critically assessed, including their role in autoimmune diseases, cancers and the global pandemic caused by COVID-19. Important issues related to their detection are also highlighted.