Rituximab use in adult glomerulopathies and its rationale

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.

Focused Jurisdictional Scan of Glomerulonephritis Medication Access in Canada: A Program Report

Purpose of Program

Glomerulonephritis (GN) is a group of rare kidney diseases that is increasingly being managed with higher cost immunosuppressive (IS) agents in Canada. Ontario Health's Ontario Renal Network (ORN) oversees the management and delivery of GN services in the province. Stakeholder surveys previously conducted by ORN identified that both clinicians and patients do not perceive access to GN medications as comprehensive or timely. The program conducted a focused jurisdictional scan among 7 provinces to inform ORN initiatives to improve access to GN medications. Specifically, the program examined clinician experience with GN access, public drug coverage criteria, and timelines for public coverage for select IS agents (ie, tacrolimus, cyclosporine, mycophenolate mofetil [MMF], mycophenolate sodium, rituximab, and eculizumab) used to manage GN in adults who live in Canada.

Methods

For the selected IS agents, a focused jurisdictional scan on medication access was conducted by ORN in 2018 and updated in July 2022. Information was obtained by searching the gray literature and/or credible online sources for public funding policies and eligibility criteria. Findings were supplemented by personal communications with provincial drug programs and consulting GN clinical experts from 7 provinces (ie, Alberta, British Columbia, Saskatchewan, Manitoba, Ontario, Nova Scotia, and Quebec).

Key Findings

Clinicians from different provinces prescribe IS agents similarly for GN indications, despite distinctions in public drug funding policies. While patients can obtain public funding for many IS agents, for GN, most provinces rely on case-by-case review processes. In addition, provinces can vary in their funding criteria and which IS agents are listed on the public formulary. For IS agents that require prior authorization or case-by-case review, timelines vary by province with decisions taking a few days to weeks. British Columbia, with a GN-specific drug formulary, had the most integrated and efficient system for patients and prescribers.

Limitations

This scan primarily relied on publicly available information for drug coverage criteria and clinician experience with access in their province. Since this scan was conducted, public drug coverage criteria and/or application processes may have changed.

Implications

While patients in most provinces have similar needs and nephrologists similar prescribing patterns, gaps still exist for publicly funded GN medications. Interprovincial differences in the drugs funded, funding criteria, and application process may affect timely and equitable access to GN medications across Canada. Given the rarity of GN, a pan-Canadian funding approach may be warranted to improve the current state.

Age of Onset and Disease Course in Biopsy-Proven Minimal Change Disease: An Analysis From the Cure Glomerulonephropathy Network

RATIONALE & OBJECTIVE

Adolescent- and adult-onset minimal change disease (MCD) may have a clinical course distinct from childhood-onset disease. We characterized the course of children and adults with MCD in the Cure Glomerulonephropathy Network (CureGN) and assessed predictors of rituximab response.

STUDY DESIGN

Prospective, multicenter, observational study.

STUDY PARTICIPANTS

CureGN participants with proven MCD on biopsy.

EXPOSURE

Age at disease onset, initiation of renin-angiotensin-aldosterone system (RAAS) blockade, and immunosuppression including rituximab during the study period.

OUTCOME

Relapse and remission, change in estimated glomerular filtration rate (eGFR), and kidney failure.

ANALYTICAL APPROACH

Remission and relapse probabilities were estimated using Kaplan-Meier curves and gap time recurrent event models. Linear regression models were used for the outcome of change in eGFR. Cox proportional hazards models were used to estimate the association between rituximab administration and remission.

RESULTS

The study included 304 childhood- (≤12 years old), 49 adolescent- (13-17 years old), and 201 adult- (≥18 years) onset participants with 2.7-3.2 years of follow-up after enrollment. Children had a longer time to biopsy (238 vs 23 and 36 days in adolescent- and adult-onset participants, respectively; P<0.001) and were more likely to have received therapy before biopsy. Children were more likely to be treated with immunosuppression but not RAAS blockade. The rate of relapse was higher in childhood- versus adult-onset participants (HR, 1.69 [95% CI, 1.29-2.21]). The probability of remission was also higher in childhood-onset disease (HR, 1.33 [95%CI, 1.02-1.72]). In all groups eGFR loss was minimal. Children were more likely to remit after rituximab than those with adolescent- or adult-onset disease (adjusted HR, 2.1; P=0.003). Across all groups, glucocorticoid sensitivity was associated with a greater likelihood of achieving complete remission after rituximab (adjusted HR, 2.62; P=0.002).

LIMITATIONS

CureGN was limited to biopsy-proven disease. Comparisons of childhood to nonchildhood cases of MCD may be subject to selection bias, given that childhood cases who undergo a biopsy may be limited to patients who are least responsive to initial therapy.

CONCLUSIONS

Among patients with MCD who underwent kidney biopsy, there were differences in the course (relapse and remission) of childhood-onset compared with adolescent- and adult-onset disease, as well as rituximab response.

PLAIN-LANGUAGE SUMMARY

Minimal change disease is a biopsy diagnosis for nephrotic syndrome. It is diagnosed in childhood, adolescence, or adulthood. Patients and clinicians often have questions about what to expect in the disease course and how to plan therapies. We analyzed a group of patients followed longitudinally as part of the Cure Glomerulonephropathy Network (CureGN) and describe the differences in disease (relapse and remission) based on the age of onset. We also analyzed rituximab response. We found that those with childhood-onset disease had a higher rate of relapse but also have a higher probability of reaching remission when compared with adolescent- or adult-onset disease. Children and all steroid-responsive patients are more likely to achieve remission after rituximab.

Biological therapy in systemic lupus erythematosus, antiphospholipid syndrome, and Sjögren's syndrome: evidence- and practice-based guidance

Systemic lupus erythematosus (SLE), antiphospholipid syndrome (APS), and Sjögren's syndrome (SS) are heterogeneous autoimmune diseases. Severe manifestations and refractory/intolerance to conventional immunosuppressants demand other options, namely biological drugs, and small molecules. We aimed to define evidence and practice-based guidance for the off-label use of biologics in SLE, APS, and SS. Recommendations were made by an independent expert panel, following a comprehensive literature review and two consensus rounds. The panel included 17 internal medicine experts with recognized practice in autoimmune disease management. The literature review was systematic from 2014 until 2019 and later updated by cross-reference checking and experts' input until 2021. Preliminary recommendations were drafted by working groups for each disease. A revision meeting with all experts anticipated the consensus meeting held in June 2021. All experts voted (agree, disagree, neither agree nor disagree) during two rounds, and recommendations with at least 75% agreement were approved. A total of 32 final recommendations (20 for SLE treatment, 5 for APS, and 7 for SS) were approved by the experts. These recommendations consider organ involvement, manifestations, severity, and response to previous treatments. In these three autoimmune diseases, most recommendations refer to rituximab, which aligns with the higher number of studies and clinical experience with this biological agent. Belimumab sequential treatment after rituximab may also be used in severe cases of SLE and SS. Second-line therapy with baricitinib, bortezomib, eculizumab, secukinumab, or tocilizumab can be considered in SLE-specific manifestations. These evidence and practice-based recommendations may support treatment decision and, ultimately, improve the outcome of patients living with SLE, APS, or SS.

Preliminary study on the efficacy of rituximab in the treatment of idiopathic membranous nephropathy: A single-centre experience

OBJECTIVE

To investigate the efficacy of rituximab in the treatment of idiopathic membranous nephropathy (IMN).

METHODS

A total of 77 patients with IMN diagnosed in both our hospital and other hospitals were included in this study; the patients were divided into two groups: a treatment-naïve group (n = 19) and a refractory/relapsed group (n = 58). The clinical data of the patients, including urine examination, blood test, safety evaluation and efficacy evaluation results, were analysed retrospectively. The changes in clinical biochemical indexes and adverse reactions were compared between the two groups before and after treatment, and the clinical efficacy of rituximab (RTX) in the treatment of primary IMN and refractory recurrent membranous nephropathy was evaluated.

RESULTS

Of the 77 patients included in this study, the average age was 48 years, and there was a male-to-female ratio of 61:16. There were 19 cases in the initial treatment group and 58 cases in the refractory/relapse group. The 24-hour urine protein quantification, cholesterol, B cell count and M-type phospholipase A2 receptor (PLA2R) results in the 77 patients with IMN after treatment were all lower than those before treatment, and the differences were statistically significant (P < 0.05). Serum albumin was higher than before treatment, and the difference was statistically significant (P < 0.05). The total remission rate in the initial and refractory/relapsed treatment groups was 84.21% and 82.76%, respectively. There was no statistical difference in the total remission rate between the two groups (P > 0.05). During treatment, nine patients (11.69%) experienced infusion-related adverse reactions, which were relieved rapidly after symptomatic treatment. The anti-PLA2R antibody titre of the refractory/relapsed group was significantly negatively correlated with serum creatinine (r = -0.187, P = 0.045) and significantly correlated with 24-hour urine protein (r = -0.490, P < 0.001). There was a positive correlation and a significant negative correlation with serum albumin (r = -0.558, P < 0.001).

CONCLUSIONS

Regardless of whether RTX is used as an initial therapy or refractory/relapsed membranous nephropathy, most patients with IMN have complete or partial remission after RTX treatment, with mild adverse reactions.

Adverse reactions of Niaoduqing granules: A systematic review and meta-analysis

BACKGROUND

The therapeutic benefits of Niaoduqing granules (NDQG) in kidney diseases has been comprehensively studied, but its adverse drug reactions remain unexplored.

OBJECTIVE

To evaluate the safety of NDQG in kidney disease treatment.

METHODS

The literature was searched in Embase, Medline via PubMed, Cochrane Library database, Wanfang database, Chinese National Knowledge Infrastructure, SinoMed, and Chinese VIP Database from inception to January 15, 2022, for randomized controlled trials (RCTs) and observational studies. The ClinicalTrials.gov website was searched for ongoing trials. The frequency and characteristics of adverse drug reactions (ADRs) were the primary and secondary outcomes, respectively. Subgroup analysis were conducted to explore the effects of clinical trial types, different kidney diseases, drug combinations and dosage on the safety of NDQG.

RESULTS

This review included 132 trials comprising 115 RCTs and 17 cohort studies. Additionally, 118 studies reported ADR rates with complete data, including 10381 participants. Regarding ADR frequency, no significant difference was observed between NDQG (7.26%) and control (8.39%) groups (RR = 0.890, 95% confidence interval (CI): 0.788-1.007); with no heterogeneity among the studies (I² = 0.0%, P = 0.958). ADR frequency in patients with chronic kidney disease (65 trials, n = 5823) was significantly lower in the NDQG treatment group than in the control group (RR = 0.810, 95% CI: 0.67-0.969, I² = 0.0%, P = 0.993); however, for patients with diabetic nephropathy there was no difference between both groups (26 trials, n = 2166, RR = 1.077, 95% CI: 0.802-1.446, I² = 0.0%, P = 0.611). Similarly, the incidence of ADR in patients on dialysis and patients with pyelonephritis and nephrotic syndrome was the same for both groups, with 95% CI overlapping the line. For different interventions, including NDQG monotherapy or its combination with other commonly used drugs (including angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, statin drugs, and compound α-keto acid) or dialysis, the incidence of ADR showed no significant difference between the experimental and control arms. The ADR in the NDQG group primarily affected the gastrointestinal system (64.74%), central and peripheral nervous system (9.07%), whole body (5.79%), and skin and appendages (4.53%). The most common clinical manifestations were diarrhea, nausea, and vomiting.

CONCLUSIONS

Our meta-analysis showed that compared with supportive therapy, the incidence of ADR was similar when NDQG was added. However, current evidence is not definitive and more well-designed and conducted RCTs are warranted to definitively establish the reliable evidence.

PROTOCOL REGISTRATION NUMBER

PROSPERO CRD 42018104227.

Rituximab for the treatment of refractory anti-glomerular basement membrane disease

BACKGROUND

Anti-glomerular basement membrane (anti-GBM) disease is a rare but severe autoantibody-mediated immune disorder. The typical clinical presentation includes rapidly progressive glomerulonephritis and often concurrent pulmonary hemorrhage. The present study is aimed to investigate the therapeutic effects of rituximab either used alone or with other immunosuppressants.

METHODS

Eight patients diagnosed with anti-GBM disease and treated with rituximab from 2014 to 2020 were retrospectively reviewed.

RESULTS

Eight patients included 5 males and 3 females with a median age of 58.5 years. They all presented severe kidney injuries and 1 patient had lung hemorrhage. At diagnosis, the median of serum creatinine was 246 µmol/L (ranging from 91 to 850 µmol/L), with 3 patients requiring dialysis. All of them received corticosteroids and plasmapheresis. Rituximab was given as either standard four weekly doses or one pulse ranging from 100 to 600 mg. After a median follow-up of 34.5 months, kidney function was partially recovered or stabilized in 5/8 (62.5%) patients, free of dialysis. Anti-GBM antibodies remained undetected in all patients during follow-up. No severe adverse effect associated with rituximab was observed.

CONCLUSION

Rituximab may be an alternative therapy in the treatment of patient with severe or refractory anti-GBM disease.

B cell phenotype, activity, and function in idiopathic nephrotic syndrome

Idiopathic nephrotic syndrome (INS) is the most frequent glomerular disease in childhood. However, its underlying etiology mechanism lacks thorough understanding. Previous studies have described INS as a T cell functional disorder resulting in increased plasma lymphocyte-derived permeability factors. In children with frequent relapses of nephrotic syndrome, the mechanism underlying the therapeutic efficacy of CD20 monoclonal antibodies in depleting B cells may provide additional evidence in exploring the critical role of B lymphocytes in INS pathogenesis. Previous studies have proposed that RTX bound to CD20 through antibody-dependent and complement-dependent cytotoxicity and led to lytic clearance of B cells. Additionally, RTX exerted an effect by blocking the interaction between B and T cells or regulating homeostasis and functions of T cell subsets. Recent studies on the development, differentiation, and activation of B-lymphocytes in glomerular diseases have suggested that the B-lymphocytes participate in the INS pathogenesis through interaction with T cells, secretion of antibodies, or production of cytokines. In this study, we aimed to provide a detailed description of the current knowledge on the development, differentiation, activity, functions, and related regulating factors of B cells involved in INS. Thus, further understanding of the immunopathogenesis of INS may offer some opportunities in precisely targeting B cells during therapeutic interventions. IMPACT: The topic "B cells play a role in glomerular disease" is a novel point, which is not completely described previously. We described interactions between T and B cells and immunoglobulin, IgG, IgM, IgE, etc. as well in glomerular disease. The research of regulatory factors associated with B cell's function, like BAFF, is a hot topic in other diseases; however, it is rare in glomerular disease.

Boas Práticas na Administração do Rituximab: Revisão Integrativa da Literatura

Introdução: O rituximab e um anticorpo monoclonal quimérico camundongo/humano, amplamente utilizado no cenário terapêutico de vários diagnósticos. Por apresentar diferentes protocolos de administração, manejo e efeitos adversos, seu uso requer atenção da equipe de saúde. Objetivo: Descrever os protocolos infusionais do rituximab na primeira infusão, nas subsequentes e na dessensibilização, e caracterizar a sua segurança. Método: Revisão integrativa da literatura. A busca pelos periódicos foi realizada nas bases de dados e bibliotecas eletrônicas: LILACS, PubMed, MEDLINE, SciELO e BDEnf. Resultados: O cruzamento dos descritores proporcionou a identificação de 413 artigos. Destes, 113 foram lidos na integra e, ao final, 16 artigos foram aplicáveis ao desenho do estudo. Os artigos foram publicados entre os anos de 2016 e 2020, com predomínio da língua inglesa (87,5%).  uanto as principais formas de administração do medicamento, nove estudos abordaram a infusão por via intravenosa (em variadas modalidades de tempo) e sete por via subcutânea. Conclusão: De acordo com a literatura cientifica, todas as modalidades de infusão intravenosa e subcutânea demostram ser seguras e eficazes se os protocolos forem adequadamente indicados e corretamente aplicados.

Adult-Onset IgA Vasculitis Presenting as an Unusual Rash and Pancolitis

A 47-year-old female presented with complaints of abdominal pain and a history of new-onset maculopapular rash. A workup including laboratory and imaging studies, colonoscopy, and biopsy was performed that led to the diagnosis of adult-onset IgA vasculitis. The patient responded well to intravenous methylprednisolone and was followed up as an outpatient where she continued with oral methylprednisolone and azathioprine. This case is noteworthy for the unusual adult-onset presentation with primarily gastrointestinal symptoms and atypical rash pattern. Furthermore, while very effective in this patient, the use of corticosteroids is a treatment decision that has some controversy in the current literature.

Rituximab for the treatment of idiopathic membranous nephropathy with nephrotic syndrome: a systematic review and meta-analysis

Background/aim

This meta-analysis comprehensively investigated the efficacy and safety of rituximab (RTX) in patients with idiopathic membranous nephropathy (IMN).

Materials and methods

We searched the MEDLINE, EMBASE and Cochrane Registry of Controlled Trials databases from January 2000 to January 2020. Studies evaluating the efficacy and safety of RTX in the treatment of IMN with nephrotic syndrome (NS) were included.

Results

Nine studies (total of 357 patients) were included in the meta-analysis. The pooled complete response and overall response (OR) rates at 12 months were 13.2% [95% con fidence interval (CI), 0.09–0.18] and 60% (95% CI, 0.48–0.72), and those at 24 months were 27.8% (95% CI, 0.22–0.34) and 66% (95% CI, 0.6–0.72), respectively. The pooled OR rates for the low-, standard-, and high-dose groups were 39.3%, 64%, and 60%, respectively, and those for the first-line and second-line groups were 58% and 54%, respectively.

Conclusion

Treatment of IMN with RTX has comparable efficacy to other immunosuppressive treatments (ISTs). RTX has the advantages of no requirement for steroids and lower rates adverse event and relapse rates. Patients who relapse or are resistant to other IST agents also respond to RTX. RTX-based regimens and other B-cell-targeted therapies may represent the future of IMN therapy.

Crescentic Glomerulonephritis: Pathogenesis and Therapeutic Potential of Human Amniotic Stem Cells

Chronic kidney disease (CKD) leads to significant morbidity and mortality worldwide. Glomerulonephritis (GN) is the second leading cause of CKD resulting in end stage renal failure. The most severe and rapidly progressive type of GN is characterized by glomerular crescent formation. The current therapies for crescentic GN, which consist of broad immunosuppressive drugs, are partially effective, non-specific, toxic and cause many serious side effects including infections, cancer, and cardiovascular problems. Therefore, new and safer therapies are needed. Human amniotic epithelial cells (hAECs) are a type of stem cell which are isolated from the placenta after birth. They represent an attractive and novel therapeutic option for the treatment of various inflammatory conditions owing to their unique and selective immunosuppressive ability, as well as their excellent safety profile and clinical applicability. In this review, we will discuss the immunopathogenesis of crescentic GN, issues with currently available treatments and how hAECs offer potential to become a new and harmless treatment option for this condition.

The mosaic of autoimmunity - A taste for more. The 12th international congress of autoimmunity 2021 (AUTO12) virtual

Notwithstanding the fact that the 12th international congress of autoimmunity (AUTO12) was held virtual this year, the number of the abstracts submitted and those presented crossed the thousand marks. Leading investigators and researchers from all over the world presented the latest developments of their research in the domain of autoimmunity and its correlation with various diseases. In terms of mechanisms of autoimmunity, an update on the mechanisms behind the association of autoimmunity with systemic diseases focusing on hyperstimulation was presented during AUTO12. In addition, a new mechanism of ASIA syndrome caused by an intrauterine contraceptive device was revealed demonstrating a complete resolution of symptoms following device removal. In regard to the correlation between autoimmunity and neurogenerative diseases, the loss of structural protein integrity as the trigger of immunological response was shown. Schizophrenia as well, and its correlation to pro-inflammatory cytokines was also addressed. Furthermore, and as it was said AUTO12 virtual due to COVID-19 pandemic, various works were dedicated to SARS-CoV-2 infection and COVID-19 in terms of autoimmune mechanisms involved in the pathogenesis, treatment and complications of COVID-19. For instance, the correlation between autoimmunity and the severity of COVID-19 was viewed. Moreover, the presence and association of autoantibodies in COVID-19 was also demonstrated, as well as the clinical outcomes of COVID-19 in patients with rheumatic diseases. Finally, immune-mediated reactions and processes secondary to SARS-CoV-2 vaccination was displayed. Due to the immense importance of all of the topics addressed and while several hundreds of works were presented which cannot be summed up in one paper, we aimed hereby to highlight some of the outstanding abstracts and presentations during AUTO12.

The Influence of Different Disease States on Rituximab Pharmacokinetics

BACKGROUND

The anti-CD20 antibody rituximab, which promotes the selective depletion of CD20 positive B cells, was the first targeted therapy that was approved for the treatment of B-cell malignancies, and it is now widely prescribed in both malignant and non-malignant, immune-related diseases. However, the cause of its various clinical responses in certain diseases, have not been clearly elucidated. The variabilities in inter-individual pharmacokinetic and the emerging evidence of the relationships between pharmacokinetic and pharmacodynamic may provide a better understanding of this drug.

METHODS

We searched and summarized the latest published articles on rituximab pharmacokinetic profiles and the pharmacokinetic/pharmacodynamic models in different patient populations, including B-cell malignancies, rheumatoid arthritis, ANCA-associated vasculitis, and glomerular kidney diseases.

RESULTS

Most pharmacokinetic data are drawn from clinical studies in oncology clinical practice. Body weight, gender, and antigen-related factors are proven to be the key factors affecting rituximab pharmacokinetics. In addition, the positive exposure-response relations were reported, which provide encouraging evidence for individualized therapies. While in immune disorders, especially in the off-labeled indications, pharmacokinetic studies are quite limited. Compared with that in B-cell malignancies, the differences in the pharmacokinetic parameters may be attributed to the different pathogeneses of diseases, mechanisms of action and dosing strategies. However, the correlation between drug exposure and clinical outcomes remains unclear.

CONCLUSION

Here, we provide an overview of the complexities associated with rituximab pharmacokinetics and pharmacodynamics in different diseases. Although many influencing factors need to be verified in future studies, a better understanding of the relationships between pharmacokinetic and pharmacodynamic may assist in optimizing rituximab clinical practice.