Can rituximab induce long-term disease remission in patients with intra-ocular non-infectious inflammation?

Rituximab in the Treatment of Non-Infectious Uveitis: A Review

Non-infectious uveitis (NIU) is an immune-mediated disorder manifesting as ocular pain, redness, floaters, and photophobia, and is a leading cause of preventable blindness. Managing NIU presents considerable challenges due to the condition's resistance to high-dose corticosteroids and various immunotherapies. This review assesses the efficacy and safety of rituximab (RTX) in the treatment of NIU, based on individual case reports and small-scale studies. A cohort of 78 patients (20 males, 58 females), with a mean onset age of 32.3 years (range 8-72), was analyzed. Juvenile idiopathic arthritis (JIA) was the most frequently associated comorbidity, affecting 28 patients, while anterior uveitis was the predominant subtype, observed in 26 of 47 cases. Prior to RTX therapy, patients had been treated with an average of 1.7 conventional immunosuppressive agents (range 0-5) and 1.1 biologics (range 0-4). RTX was introduced following the failure of high-dose corticosteroids, immunosuppressive drugs, and biologics to control the uveitis. The median time from diagnosis to RTX initiation was 7.7 years (range 0.25-21). Post-RTX, 44.2% of patients experienced improvement in visual acuity, 79.5% achieved resolution of ocular inflammation, and 8.9% showed partial improvement. Additionally, 81.1% were able to reduce their corticosteroid dosage. Overall, 88.6% (69 out of 78) demonstrated a positive response to RTX treatment. These findings indicate that RTX may serve as an effective therapeutic option for NIU unresponsive to steroids and multiple immunotherapies. It may also warrant consideration as a potential first-line treatment in certain cases.

Repurposing of rituximab biosimilars to treat B cell mediated autoimmune diseases

Rituximab, the first monoclonal antibody approved for the treatment of lymphoma, eventually became one of the most popular and versatile drugs ever in terms of clinical application and revenue. Since its patent expiration, and consequently, the loss of exclusivity of the original biologic, its repurposing as an off-label drug has increased dramatically, propelled by the development and commercialization of its many biosimilars. Currently, rituximab is prescribed worldwide to treat a vast range of autoimmune diseases mediated by B cells. Here, we present a comprehensive overview of rituximab repurposing in 115 autoimmune diseases across 17 medical specialties, sourced from over 1530 publications. Our work highlights the extent of its off-label use and clinical benefits, underlining the success of rituximab repurposing for both common and orphan immune-related diseases. We discuss the scientific mechanism associated with its clinical efficacy and provide additional indications for which rituximab could be investigated. Our study presents rituximab as a flagship example of drug repurposing owing to its central role in targeting cluster of differentiate 20 positive (CD20) B cells in 115 autoimmune diseases.

Efficacy of Rituximab Treatment in Vogt-Koyanagi-Harada Disease Poorly Controlled by Traditional Immunosuppressive Treatment

PURPOSE

To evaluate the efficacy of Rituximab (RTX) therapy in patients affected by Vogt-Koyanagi-Harada (VKH) disease poorly controlled by traditional immunosuppressive treatment.

METHODS

Retrospective case series of recurrent VKH uveitis treated with intravenous RTX between January 2019 and November 2020. All patients were treated with intravenous RTX and underwent complete ophthalmic examination, best-corrected visual acuity (BCVA), fundus photography, subfoveal choroidal thickness (SFCT) measurement on enhanced depth imaging optical-coherence tomography (EDI-OCT), fluorescein, and indocyanine green angiography.

RESULTS

Five patients were included. All patients received at least 3 RTX infusions. Mean BCVA improved from 20/32 Snellen equivalent at baseline before RTX treatment to 20/28 Snellen equivalent (p = .008). Mean SFCT on EDI-OCT showed a reduction from 564.4 µm(SD = 176.2) to 280.0 µm(SD = 140.4) (p = .015). Follow-up ranged from 12 to 21 months, with a mean of 18.2 ± 3.7 months.

CONCLUSIONS

In these case series, RTX was effective in VHK disease poorly controlled by traditional immunosuppressive treatment.

Rituximab for non-infectious Uveitis and Scleritis

Purpose

To provide a comprehensive review of rituximab use for the treatment of non-infectious uveitis and scleritis.

Methods

Review of literature through December 2020.

Results

Individual data was available for 229 patients with refractory non-infectious uveitis (n = 108) or scleritis (n = 121) who received treatment with rituximab (RTX). Rituximab was generally utilized as third-line or later treatment (uveitis: 67/90, 74.4%; scleritis: 90/96, 93.8%) at a mean of 33.5 months following the diagnosis of uveitis (range = 0 to 168.0 months; median = 24.0 months) and 39.4 months after diagnosis of scleritis (range = 1.0 to 168.0 months; median = 21.0 months). Patients with non-infectious uveitis and scleritis either received prior treatment with corticosteroids only (uveitis: 18/90, 20%; scleritis: 4/94, 4.3%), or with one (uveitis: 19/90, 21.1%; scleritis: 30/94, 31.9%), two (uveitis: 11/90, 12.2%; scleritis 27/94, 28.7%), or three or more (uveitis: 37/90, 41.1%; scleritis: 31/94, 33.0%) corticosteroid-sparing immunosuppressive agents with or without corticosteroids before initiation of RTX treatment. The rheumatologic protocol (two infusions of 1 gram of RTX separated by 14 days) was utilized most frequently (uveitis: 45/87, 51.7%; scleritis: 87/114, 76.3%), followed by the Foster protocol (eight weekly infusions of 375 mg/m² RTX; uveitis: 18/87, 20.7%; scleritis: 10/114, 8.8%), and the oncologic protocol (four weekly infusions of 375 mg/m² RTX; uveitis: 5/87, 5.7%; scleritis: 6/114, 5.3%). Various other off-label regimens were used infrequently (uveitis: 19/87, 21.8%; scleritis 11/114, 9.6%). Rituximab treatments resulted in a positive therapeutic response for the majority of patients with non-infectious uveitis (81/97, 83.5%). Commonly treated uveitic diagnoses included non-paraneoplastic autoimmune retinopathy (30/107, 28.0%), juvenile idiopathic arthritis (21/107, 19.6%), Vogt-Koyanagi-Harada disease (12/107, 11.2%), and Behçet disease (11/107, 10.3%). Cases of non-infectious scleritis were most commonly attributed to granulomatosis with polyangiitis (75/121, 62.0%) and rheumatoid arthritis (15/121, 12.4%), and showed an even greater rate of positive therapeutic response (112/120, 93.3%) following RTX treatment. No side effects were reported in 76.3% (74/97) of uveitis and 85.5% (71/83) scleritis cases. Of those cases associated with RTX-induced adverse events, the most common were infusion reactions of various severity (11/35, 31.4%).

Conclusions

Overall, RTX appeared to be both effective and well-tolerated as second or third-line therapy for patients with non-infectious uveitis and scleritis.

A Review of the Various Roles and Participation Levels of B-Cells in Non-Infectious Uveitis

Non-infectious uveitis is an inflammatory disorder of the eye that accounts for severe visual loss without evident infectious agents. While T cells are supposed to dominate the induction of inflammation in non-infectious uveitis, the role of B cells in the pathogenesis of this disease is obscure. Therefore, this review aimed to discuss diverse B-cell participation in different non-infectious uveitides and their roles in the pathogenesis of this disease as well as the mechanism of action of rituximab. Increasing evidence from experimental models and human non-infectious uveitis has suggested the participation of B cells in non-infectious uveitis. The participation levels vary in different uveitides. Furthermore, B cells play multiple roles in the pathogenic mechanisms. B cells produce autoantibodies, regulate T cell responses via antibody-independent functions, and constitute ectopic lymphoid structures. Regulatory B cells perform pivotal anti-inflammatory functions in non-infectious uveitis. Rituximab may work by depleting pro-inflammatory B cells and restoring the quantity and function of regulatory B cells in this disease. Identifying the levels of B-cell participation and the associated roles is beneficial for optimizing therapy. Diversified experimental model choices and emerging tools and/or methods are conducive for future studies on this topic.

Optimising drug therapy for non-infectious uveitis

INTRODUCTION

Uveitis encompasses a wide variety of sight-threatening diseases characterized by intraocular inflammation. It is often classified as infectious and non-infectious uveitis. Unlike infectious uveitis, a distinct infectious agent cannot be identified in non-infectious uveitis and disease origin is usually autoimmune, drug related, or idiopathic.

THE ISSUE AT HAND

Non-infectious uveitis can often have a relapsing-remitting course, making it difficult to treat, and poses a significant challenge to ophthalmologists. The autoimmune nature of non-infectious uveitis warrants the use of anti-inflammatory and immunomodulatory agents for disease control. However, a subset of patients has persistent or recurrent ocular inflammation despite appropriate treatment, stressing the need for newer therapies aimed at more specific inflammatory targets such as tumour necrosis factor (TNF) alpha agents, anti-interleukin agents, and anti-interleukin receptor agents.

OBJECTIVES

This article discusses the various medical options available for the treatment of non-infectious uveitis in the light of the most recent evidence.

CONCLUSION

Successful management of non-infectious uveitis requires the clinician carefully balance advantages and disadvantages of each new and old therapy while considering individual circumstances. Counselling regarding the benefits and complications of each therapy can help patients make an informed choice.

A review and update on orphan drugs for the treatment of noninfectious uveitis

Introduction

Uveitis, a leading cause of preventable blindness around the world, is a critically underserved disease in regard to the medications approved for use. Multiple immunomodulatory therapy (IMT) drugs are appropriate for uveitis therapy but are still off-label. These IMT agents, including antimetabolites, calcineurin inhibitors, alkylating agents, and biologic agents, have been designated as “orphan drugs” and are widely used for systemic autoimmune diseases or organ transplantation.

Area covered

The purpose of this paper is to comprehensively review and summarize the approved orphan drugs and biologics that are being used to treat systemic diseases and to discuss drugs that have not yet received approval as an “orphan drug for treating uveitis” by the US Food and Drug Administration (FDA).

Our perspective

IMT, as a steroid-sparing agent for uveitis patients, has shown promising clinical results. Refractory and recurrent uveitis requires combination IMT agents. IMT is continued for a period of 2 years while the patient is in remission before considering tapering medication. Our current goals include developing further assessments regarding the efficacy, optimal dose, and safety in efforts to achieve FDA approval for “on-label” use of current IMT agents and biologics more quickly and to facilitate insurance coverage and expand access to the products for this orphan disease.

Non-Infectious Uveitis: Optimising the Therapeutic Response

Non-infectious uveitis mainly affects the working-age population and can contribute to significant social and economic burden. It comprises a heterogeneous group of conditions with varied aetiology. Precise and early diagnosis, excluding masquerade syndromes, is the key to early therapeutic intervention. Treatment should be appropriately selected according to the anatomical sites of inflammation, the diagnosis and known prognosis, and whether there is a systemic inflammatory drive. Corticosteroids in the form of local or systemic therapy form the mainstay of treatment; however, due to unacceptable side effects, the need for long-term use or suboptimal response, corticosteroid-sparing medications may need to be considered early on in the management of non-infectious uveitis. With newer insights into the immunopathology of uveitis and the availability of biologic agents, treatment can be tailored according to individual needs. Many patients have systemic involvement, and hence a multidisciplinary approach is often required to achieve the best outcome in an individual. Patient involvement in the management of non-infectious uveitis, ensuring compliance, and continual monitoring of both the treatment and therapeutic response are the key to achieving optimal outcomes.

Progress in the understanding and utilization of biologic response modifiers in the treatment of uveitis

Uveitis is the third most common cause of blindness in developed countries. Considering the systemic and local complications of long-term corticosteroid therapy and the intolerance due to side effects and ineffectiveness of conventional chemotherapy, use of biologic response modifiers is a reasonable alternative in the treatment of non-infectious uveitis and persistent uveitic macular edema. The majority of the evidence presented here comes from open uncontrolled analyses. Based on these studies, tumor necrosis factor alpha inhibitors, especially infliximab and adalimumab, have been shown to be effective in the treatment of non-infectious uveitis in numerous studies. More research is necessary, particularly multi-center randomized clinical trials, to address the choice of biologic response modifier agent and the length of treatment as we employ biologic response modifiers in different types of uveitis and persistent uveitic macular edema.

Pharmacotherapy for uveitis: current management and emerging therapy

Uveitis, a group of conditions characterized by intraocular inflammation, is a major cause of sight loss in the working population. Most uveitis seen in Western countries is noninfectious and appears to be autoimmune or autoinflammatory in nature, requiring treatment with immunosuppressive and/or anti-inflammatory drugs. In this educational review, we outline the ideal characteristics of drugs for uveitis and review the data to support the use of current and emerging therapies in this context. It is crucial that we continue to develop new therapies for use in uveitis that aim to suppress disease activity, prevent accumulation of damage, and preserve visual function for patients with the minimum possible side effects.

Autoimmune and autoinflammatory mechanisms in uveitis

The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of T_reg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8⁺ T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders.

Update on the use of systemic biologic agents in the treatment of noninfectious uveitis

Uveitis is one of the leading causes of blindness worldwide. Noninfectious uveitis may be associated with other systemic conditions, such as human leukocyte antigen B27-related spondyloarthropathies, inflammatory bowel disease, juvenile idiopathic arthritis, Behçet’s disease, and sarcoidosis. Conventional therapy with corticosteroids and immunosuppressive agents (such as methotrexate, azathioprine, mycophenolate mofetil, and cyclosporine) may not be sufficient to control ocular inflammation or prevent non-ophthalmic complications in refractory patients. Off-label use of biologic response modifiers has been studied as primary and secondary therapeutic agents. They are very useful when conventional immunosuppressive therapy has failed or has been poorly tolerated, or to treat concomitant ophthalmic and systemic inflammation that might benefit from these medications. Biologic therapy, primarily infliximab, and adalimumab, have been shown to be rapidly effective for the treatment of various subtypes of refractory uveitis and retinal vasculitis, especially Behçet’s disease-related eye conditions and the uveitis associated with juvenile idiopathic arthritis. Other agents such as golimumab, abatacept, canakinumab, gevokizumab, tocilizumab, and alemtuzumab may have great future promise for the treatment of uveitis. It has been shown that with proper monitoring, biologic therapy can significantly improve quality of life in patients with uveitis, particularly those with concurrent systemic symptoms. However, given high cost as well as the limited long-term safety data, we do not routinely recommend biologics as first-line therapy for noninfectious uveitis in most patients. These agents should be used with caution by experienced clinicians. The present work aims to provide a broad and updated review of the current and in-development systemic biologic agents for the treatment of noninfectious uveitis.