Long-term prognosis of adult patients with steroid-dependent minimal change nephrotic syndrome following rituximab treatment

Immunosuppression for adult steroid-dependent or frequently relapsing nephrotic syndrome: A systematic review and meta-analysis

OBJECTIVE

There is limited evidence on which immunosuppressive agents produce the best outcomes for adult patients with steroid-dependent or frequently relapsing nephrotic syndrome (SDNS/FRNS). This review compares the remission rate and adverse effects of various immunosuppressants used.

METHODS

Studies of adult patients with biopsy-proven SDNS/FRNS, administered any immunosuppressive agents and reported complete remission results as one of the clinical outcomes were included. Articles were independently screened by two researchers. ROBINS-I was used for risk of bias assessment. Random-effects model was used for statistical analysis and corresponding 95% confidence intervals (CIs) were calculated.

RESULTS

574 patients across 28 studies were included in the analysis. Patients receiving rituximab have a complete remission rate of 89% (95% CI = 83% to 94%; τ2 = 0.0070; I2 = 62%; overall p < 0.01, low certainty) and adverse event rate of 0.26, cyclosporine (CR 40%; 95% CI = 21% to 59%; τ2 = 0.0205; I2 = 55%; overall p = 0.08, low certainty), tacrolimus (CR 84%; 95% CI = 70% to 98%; τ2 = 0.0060; I2 = 33%; overall p = 0.21, moderate certainty), mycophenolate mofetil (CR 82%; 95% CI = 74% to 90%; τ2 < 0.0001; I2 = 15%; overall p = 0.32, moderate certainty) and cyclophosphamide (CR 79%; 95% CI = 69% to 89%; τ2 = 0; I2 = 0%; overall p = 0.52, moderate certainty).

CONCLUSION

Among the commonly used immunosuppressive agents, only rituximab has a statistically significant effect in achieving complete remission among patients with SDNS/FRNS and has a relatively good safety profile, but this is limited by low quality of evidence with high degree of heterogeneity causing a lack of statistical power.

Relapse during and after regular single-dose rituximab treatment in adult patients with steroid-dependent nephrotic syndrome

BACKGROUND

Rituximab is widely used in patients with steroid-dependent nephrotic syndrome. However, information on the effect of long-term rituximab treatment is limited. This study examined the efficacy of rituximab during and after treatment in adult patients with steroid-dependent nephrotic syndrome.

METHODS

This retrospective cohort study included 30 patients with steroid-dependent nephrotic syndrome. Patients received regular single-dose rituximab (500 mg) intravenously every 6 months. Discontinuation of rituximab was considered after four to six doses if there was no recurrence of nephrotic syndrome. Glucocorticoid discontinuation with remission, first relapse after rituximab initiation, and relapse after regular rituximab treatment discontinuation were evaluated.

RESULTS

The median age was 38 (range 18-67) years. Of 30 patients, 13 and 17 were men and women, respectively. Prior to rituximab treatment, the median number of nephrotic syndrome relapses in the patients was 5 (range 2- > 20). The 1 year discontinuation rate of glucocorticoids with remission was 83%. All patients discontinued glucocorticoid treatment at least once until 3 years and 7 months. The 1 and 2 year relapse rates after initiation of rituximab treatment were 0% and 3%, respectively. 25 patients discontinued regular rituximab treatment after a median number of six (4-12) doses. Six patients relapsed after discontinuing rituximab, and the 1 and 2 year relapse rates after the last regular rituximab treatment were 9% and 25%, respectively.

CONCLUSION

All patients with steroid-dependent nephrotic syndrome who received rituximab could discontinue glucocorticoid treatment with remission, and three-fourths of the patients remained in remission for > 2 years after discontinuing rituximab treatment.

A case of minimal change nephrotic syndrome complicated by Kimura disease treated with rituximab

Kimura disease (eosinophilic granuloma of the soft tissue) is a benign granulomatous disease complicated by nephrotic syndrome. Herein, we report a case of recurrent minimal change nephrotic syndrome (MCNS) complicated by Kimura disease that was successfully treated with rituximab. A 57-year-old man presented to our hospital with relapsed nephrotic syndrome with worsening swelling of the right anterior ear and elevated serum IgE. MCNS was diagnosed on renal biopsy. Treatment with 50 mg of prednisolone rapidly placed the patient in remission. Therefore, RTX 375 mg/m2 was added to the treatment regimen, and steroid therapy was tapered. Early steroid tapering was successful, and the patient is currently in remission. In this case, the nephrotic syndrome flare-up was accompanied by worsening Kimura disease. Rituximab reduced the worsening of symptoms related to Kimura disease, including head and neck lymphadenopathy and elevated IgE levels. Kimura disease and MCNS may share a common IgE-mediated type I allergic condition. Rituximab effectively treats these conditions. In addition, rituximab suppresses Kimura disease activity in patients with MCNS, enables early tapering of steroids, and reduces the total dose of steroids.

Repetitive administration of rituximab can achieve and maintain clinical remission in patients with MCD or FSGS

Minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) are glomerulopathies associated with nephrotic syndrome. Primary forms of these diseases are treated with various regimes of immunosuppression. Frequently relapsing or glucocorticoid-dependent courses remain challenging. Here, a B-cell-depleting strategy with rituximab represents a salvage option although data are sparse in the adult population. In particular, there is limited evidence on the efficacy of restoring remission after initial successful treatment with rituximab and whether patients benefit from an individualized, relapse-based approach. We identified 13 patients who received multiple therapies with rituximab from the FOrMe-registry (NCT03949972), a nationwide registry for MCD and FSGS in Germany, or from the University Hospital of Cologne. Disease status, changes in serum creatinine, proteinuria, and time to relapse were evaluated. Relapse-free survival was compared to the patients' previous therapy regimens. Through all treatment cycles, an improvement of disease activity was shown leading to a complete remission in 72% and partial remission in 26% after 3 ([Formula: see text]0.001) and 6 months ([Formula: see text]0.001). Relapse-free survival increased from 4.5 months (95%-CI 3-10 months) to 21 months (95%-CI 16-32 months) ([Formula: see text]0.001) compared to previous immunosuppression regimens with no loss in estimated glomerular filtration over time (p = 0.53). Compared to continuous B-cell depletion, an individualized relapse-based approach led to a reduced rituximab exposure and significant cost savings. Relapse-based administration of rituximab in patients with MCD/FSGS with an initial good clinical response did not result in a decreased efficacy at a median follow-up duration of 110 months. Thus, reinduction therapies may provide an alternative to continuous B-cell-depletion and reduce the long-term side effects of continuous immunosuppression.

Review of the Role of Rituximab in the Management of Adult Minimal Change Disease and Immune-Mediated Focal and Segmental Glomerulosclerosis

Background

Minimal change disease and primary FSGS are podocytopathies but are also immune-mediated diseases. Rituximab acts via multiple mechanisms by tilting the balance between autoreactive B and T cells in favor of regulatory B and T cells. The consequences are decreased production of cytokines, chemokines, and permeability factors by these cells. In the past decade, we have seen the discovery of autoantibodies mediating nephrotic syndrome (anti-annexin A2 antibody, anti-UCHL1 antibody, and anti-nephrin antibody), and rituximab decreases their production. Rituximab also binds to podocyte SMPDL3b and has direct podocyte actions.

Summary

Rituximab's role in managing these primary podocytopathies has been discussed in this brief review. Rituximab has been used extensively in children and adults with frequently relapsing and steroid-dependent nephrotic syndrome. However, rituximab is not very promising in adult steroid-resistant nephrotic syndrome. Although ofatumumab would cause prolonged B-cell depletion and is fully humanized, it is unclear if it is superior to rituximab in preventing relapse of nephrotic syndrome.

Key Messages

Rituximab therapy can induce prolonged remission in adults with frequently relapsing and steroid-dependent nephrotic syndrome. However, no good data exist on using rituximab in steroid-resistant nephrotic syndrome.

Persistent SARS-CoV-2 Infection in a Patient with Nephrotic Syndrome under Rituximab Therapy: Successful Treatment with a Combination of Remdesivir and Monoclonal Antibodies

Rituximab is an effective treatment for frequently relapsing/steroid-dependent nephrotic syndrome, but there is concern about infections caused by humoral immunodeficiency. We herein report a case of prolonged (>7 weeks) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A 24-year-old man with minimal change disease treated with rituximab developed SARS-CoV-2 infection. The clinical response to remdesivir was soon transiently abolished. Treatment with casirivimab and imdevimab (REGEN-COV) monoclonal antibodies in combination with remdesivir resulted in complete clearance of the infection. The REGEN-COV antibody cocktail may improve the outcome of SARS-CoV-2 infection in patients with humoral immunodeficiency.

Use of Rituximab as an Off-Label Medication in Glomerular Diseases: Clinical Perspective

OBJECTIVES

The aim of this study was to review the use rituximab (RTX) and outcomes in immune-mediated glomerular diseases (glomerulonephritis [GN]) and to compare it to the established literature.

METHODS

Adult GN patients who received RTX between January 2014 and January 2018 in three public hospitals were reviewed. Membranous nephropathy (MN) and minimal change disease (MCD) were considered diseases with the literature supporting RTX use. Lupus nephritis (LN), primary focal segmental glomerulosclerosis (1o FSGS), IgA nephropathy, IgG4-related disease (IgG4-RD), and C3GN had insufficient literature support for RTX use. Clinical remission was assessed 6 months after receiving RTX.

RESULTS

A total of 61 cases were analyzed. RTX was an add-on therapy in 87%. The remission rate was 95% in the MCD and MN versus 56% in the off-label group (p = 0.002). LN patients had a mean initial estimated glomerular filtration rate (eGFR) of 69 mL/min. All class III LN achieved remission, and 11 of 21 class IV achieved remission. The mean initial eGFR for 1o FSGS was 33 mL/min, and it did not improve, and only 2 of 5 had partial resolution of proteinuria. Proteinuria improved in 3 of 5 IgG4-RD cases with eGFR stabilization but failed to improve in C3GN cases with eGFR deterioration. Vasculitis cases (6 ANCA-associated vasculitis and 2 IgA vasculitis) were analyzed separately. Remission was achieved in only 2 ANCA-associated vasculitis cases, and none in IgA vasculitis cases.

CONCLUSIONS

Our data support the use of RTX in resistant MCD and MN. RTX showed success in LN and IgG4-RD but not FSGS or C3GN. The small number of cases of vasculitis does not allow drawing a conclusion on RTX effectiveness.

The management of membranous nephropathy - an update

In the last decades several important advances have taken place in the understanding of the pathogenesis underlying membranous nephropathy, which have sparked renewed interest in its management. Four landmark trials in membranous nephropathy, and a fifth clinical trial-which was a pilot study-, have been published in the last years. The results from some of these trials have had a significant impact in the recommendations included in the 2021 Kidney Disease: Improving Global Outcomes (KDIGO) Guideline for the Management of Glomerular Diseases, which represent a significant step forward compared to the previous guideline in several aspects such as diagnosis, disease monitoring and treatment strategies. However, considering the rapidly evolving advances in the knowledge of membranous nephropathy and the recent publication of the STARMEN and RI-CYCLO trials, several recommendations contained in the guideline warrant updates. This manuscript provides a perspective of the Immunonephrology Working Group of the European Renal Association (ERA) regarding the management of membranous nephropathy in native kidneys of adult patients.

Successful Pregnancies in a Patient with Childhood-onset Steroid-dependent Nephrotic Syndrome during Rituximab Maintenance Therapy

There are an increasing number of reports on the safe use of rituximab (RTX), a chimeric anti-CD20 monoclonal antibody, in pregnant women with hematological malignancies or refractory autoimmune diseases. In 2014, the use of RTX for patients with complicated steroid-dependent nephrotic syndrome (SDNS) was approved in Japan. We herein report a woman with childhood-onset complicated SDNS due to focal and segmental glomerulosclerosis, who had two successful pregnancies while receiving RTX maintenance therapy. No adverse complications were observed during the pregnancies, and she delivered healthy newborns. This case suggested that RTX may be used safely in pregnant women complicated with SDNS.

The Efficacy and Safety of Rituximab for Childhood Steroid-Dependent Nephrotic Syndrome: A Systematic Review and Meta-Analysis

Objectives: Rituximab (RTX), a possible alternative treatment option, is recognized as a new therapeutic hope for the treatment of steroid-dependent nephrotic syndrome (SDNS) in children. However, the efficacy and safety of RTX in the treatment of childhood SDNS are still controversial. The objective of this study was to evaluate the efficacy and safety of RTX treatment in children with SDNS. Study Design: Six randomized controlled trials (RCTs) and one retrospective comparative control study data from studies, performed before January 2021 were collected, from PubMed, Cochrane Library, Embase, and Web of Science. The studies evaluating the efficacy and safety of RTX in childhood SDNS were included. Results: Six RCTs and one retrospective comparative control study were included in our analysis. Compared with the control group, the RTX treatment group achieved a higher complete remission rate (OR = 5.21; 95% CI, 3.18-8.54; p < 0.00001), and we found significant differences between the two groups on serum albumin level (MD = 0.88; 95% CI, 0.43-1.33; p = 0.0001) and estimated glomerular filtration rate (MD = 6.43; 95% CI, 2.68-10.19; p = 0.0008). However, RTX treatment did not significantly lower serum creatinine levels nor did it significantly reduce the occurrence of proteinuria. In addition, we found no advantages with RTX on treatment safety. Conclusions: RTX has shown satisfactory characteristics in terms of efficacy and may be a promising treatment method for SDNS in children. However, the long-term effects have not been fully evaluated and should be further studied through randomized clinical trials.

Clinical Characteristics and Outcomes of Adults with Nephrotic Syndrome Due to Minimal Change Disease

PURPOSE

Minimal change disease (MCD) is considered a relatively benign glomerulopathy, as it rarely progresses to end-stage kidney disease. The aim of this study was to describe the characteristics and outcomes of adults with MCD and identify potential risk factors for relapse.

PATIENTS & METHODS

We retrospectively studied a cohort of adults with biopsy-proven MCD in terms of clinical features and treatment outcomes. Baseline characteristics and outcomes were recorded and predictors of relapse were analyzed using logistic regression multivariate analysis.

RESULTS

59 patients with adult-onset primary MCD with nephrotic syndrome were included. Mean serum creatinine at diagnosis was 0.8 mg/dL (±2.5) and estimated GFR (eGFR) was 87 mL/min/1.73 m² (±29.5). Mean serum albumin was 2.5 g/dL (±0.8) and 24 h proteinuria 6.8 g (±3.7). Microscopic hematuria was detected in 35 (58.5%) patients. 42 patients received prednisone alone, six patients received prednisone plus cyclophosphamide, five patients received prednisone plus cyclosporine, one patient received prednisone plus rituximab and five patients did not receive immunosuppression at all since they achieved spontaneous remission. During a mean follow up time of 34.7(22.1) months, 46.1% of patients experienced at least one episode of relapse. The mean age of patients who did not experience a relapse was significantly higher than that of patients who relapsed while relapsers had a significantly longer duration of 24 h proteinuria prior to biopsy compared to non-relapsers. Overall, 10% of patients experienced acute kidney injury while the mean eGFR at the end was 82 mL/min/1.73 m² (±29.1) and one patient ended up in chronic dialysis. Overall, the proportion of non-relapsers, who experienced acute kidney injury (17%) was significantly higher than the one recorded among relapsers (0%).

CONCLUSION

In this series of patients, almost 46% of adult-onset nephrotic MCD patients experienced a relapse, although their renal progression was rare. Younger onset age was an independent risk factor for relapse in adult-onset MCD patients.

Consolidation Treatment and Long-Term Prognosis of Rituximab in Minimal Change Disease and Focal Segmental Glomerular Sclerosis

Purpose

There is currently a lack of studies investigating long-term prognosis and the necessity of further rituximab (RTX) consolidation treatment for minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS). The aim of this study was to evaluate the efficacy of RTX for these diseases and to investigate whether a consolidation treatment can lower risks of relapse and reinforce long-term remission.

Patients and Methods

A retrospective study was conducted. The relapse and remission of 70 patients treated with 1 course of RTX treatment (4 infusions of 375 mg/m2) over a median follow-up time of 27 months (12–60 months) were analyzed. The rates of patients that were able to achieve non-relapse for a duration of 24 months between RTX consolidation therapy and non-consolidation therapy were compared.

Results

There were 67 cases (95.71%) of remission and 3 cases (4.29%) of non-remission. The average number of relapses decreased from 3.7±2.5 times before the treatment to 0.8±1.8 times after treatment (P <0.001). The average avannual number of relapses decreased from 1.3±1.2 times/year to 0.2±0.3 times/year (P <0.001). The results from the Cox proportional-hazards model showed that the risk of relapse in patients who received RTX non-consolidation treatment was significantly higher than those with consolidation treatment (odds ratios (OR) 20.9, 95% confidence intervals (CI) OR 5.7–75.7, p<0.001). The 24-month relapse-free rate was also significantly higher in patients with consolidation therapy compared with non-consolidation therapy (86.36% vs 25%, p<0.001). No adverse events were recorded.

Conclusion

RTX is highly effective in treating MCD and FSGS, and RTX consolidation therapy may be recommended to reinforce long-term remissions.

Spontaneous remission of minimal change nephrotic syndrome in an elderly man

Minimal change nephrotic syndrome (MCNS) cases achieving spontaneous remission without external factors are rarely reported. We report a case of MCNS that achieved spontaneous remission without external factors that triggered its onset. An 82-year-old male patient was admitted to the hospital for close examination of nephrotic syndrome. Renal biopsy was performed and MCNS was diagnosed. Owing to the patient's age and history of foot and microvascular arteriovenous thrombosis, we did not start immunosuppressive drugs, including steroids, and opted for conservative management. After conservative treatment, proteinuria gradually decreased, and the patient achieved complete remission. Given that the patient had a history of urinary protein and thrombosis, recurrence of MCNS was considered again this time. In addition, the involvement of external factors that trigger the onset of MCNS was not found. In conclusion, in elderly-onset MCNS, clinicians generally hesitate to initiate treatment with an immunosuppressive drug, containing steroids, because of its many complications. Thus, our data provide valuable insight into MCNS.

Efficacy and safety of rituximab in adult frequent-relapsing or steroid-dependent minimal change disease or focal segmental glomerulosclerosis: a systematic review and meta-analysis

Background

The efficacy and safety of rituximab (RTX) in adult frequent-relapsing (FR) or steroid-dependent (SD) nephrotic syndrome (NS), including minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS), are still inconclusive.

Methods

We performed a systematic review and meta-analysis registered in  PROSPERO (CRD42019148102) by pooling data of cohort studies or case series on adult patients with difficult-to-treat NS. Steroid-resistant NS was excluded. The primary outcomes were the complete remission (CR) rate and the relapse rate. Partial remission (PR) rate, no response (NR) rate and adverse events were the secondary outcomes. A random-effects model was performed for all the outcomes.

Results

We included 21 studies involving 382 adult MCD/FSGS subjects with a median follow-up duration from 12 to 43 months. RTX treatment induced a pooled 84.2% CR rate [95% confidence interval (CI): 67.7–96.3%], while MCD patients had a high 91.6% CR rate and FSGS patients a moderate 43% CR rate. However, 27.4% (95% CI 20.7–34.5%) of the patients relapsed during the follow-up. The pooled PR and NR rates were 5.8% (95% CI 1.2–12.5%) and 5.2% (95% CI 0.0–15.0%), respectively. RTX was associated with trivial adverse events and good tolerance.

Conclusions

In summary, by pooling results of current pilot studies, RTX may be an effective and relatively safe alternative for most adult FR or SD MCD/FSGS to displace calcineurin inhibitors or prednisone in the hierarchy of treatment. More clinical trials comparing RTX with other immunosuppressants and concerning the long-term adverse events are needed.

Efficacy of repeat-dose rituximab maintenance therapy for minimal change disease in adults

BACKGROUND

Rituximab (RTX) has been reported to effectively treat minimal change disease (MCD) in adults. However, the efficacy of RTX as maintenance therapy, especially in older patients, remains unclear. This study aimed to evaluate the efficacy of repeat-dose RTX maintenance therapy regardless of age.

METHODS

We retrospectively reviewed the clinical courses of 13 biopsy-proven adult MCD patients receiving RTX and evaluated the relapse rate, concomitant steroid and immunosuppressant use, relationship between B-cell depletion time and relapse, and adverse events.

RESULTS

Mean patient age at start of RTX therapy was 51.5 ± 20.1 years. Each RTX induction consisted of a single 375 mg/m² dose. One patient received two RTX doses with a 1-year interval. The remaining 12 patients received RTX at 6-month intervals up to four times after RTX introduction. The median observation period was 28 (16-60) months after RTX induction, median relapse frequency was significantly decreased from 0.83 (0.18-1.92) to 0 (0-0.71) times/year (P < 0.001), and median prednisolone dose was reduced from 25 (5-40) mg to 2.5 (0-10) mg (P < 0.001). CD19-positive B cells remained depleted during RTX administration in 6-month intervals. No serious adverse events were observed after RTX administration.

CONCLUSIONS

Repeat-dose RTX as maintenance therapy efficiently prevented recurrence and was well tolerated in adult MCD patients including older. This regimen has the potential to maintain prolonged remission. Future studies in larger cohorts are needed to identify the optimal dose and frequency and evaluate the long-term effectiveness and safety of this regimen.

Rituximab use in adult glomerulopathies and its rationale

Glomerulopathies are one of the leading causes of end-stage renal disease. In the last years, clinical research has made significant contributions to the understanding of such conditions. Recently, rituximab (RTX) has appeared as a reasonably safe treatment. The Kidney Disease: Improving Global Outcomes guidelines (KDIGO) recommended RTX only as initial treatment in antineutrophil cytoplasm antibody associated vasculitis (AAV) and in non-responders patients with lupus nephritis (LN), but these guidelines have not been updated since 2012. Nowadays, RTX seems to be at least as effective as other immunosuppressive regimens in idiopathic membranous nephropathy (IMN). In minimal-change disease, (MCD) this drug might allow a long-lasting remission period in steroid-dependent or frequently relapsing patients. Preliminary results support the use of RTX in patients with pure membranous LN and immunoglobulin-mediated membranoproliferative glomerulonephritis (MPGN), but not in patients with class III/IV LN or complement-mediated MPGN. No conclusion can be drawn in idiopathic focal segmental glomerulosclerosis (FSGS) and anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN) because studies are small, heterogeneous, and scarce. Lastly, immunosuppression including RTX is not particularly useful in IgA nephropathy. This review presents the general background, outcomes, and safety for RTX treatment in different glomerulopathies. In this regard, we describe randomized controlled trials (RCTs) performed in adults, whenever possible. A literature search was performed using clinicaltrials.gov and PubMed.

Rituximab use in adult glomerulopathies and its rationale

Glomerulopathies are one of the leading causes of end-stage renal disease. In the last years, clinical research has made significant contributions to the understanding of such conditions. Recently, rituximab (RTX) has appeared as a reasonably safe treatment. The Kidney Disease: Improving Global Outcomes guidelines (KDIGO) recommended RTX only as initial treatment in antineutrophil cytoplasm antibody associated vasculitis (AAV) and in non-responders patients with lupus nephritis (LN), but these guidelines have not been updated since 2012. Nowadays, RTX seems to be at least as effective as other immunosuppressive regimens in idiopathic membranous nephropathy (IMN). In minimal-change disease, (MCD) this drug might allow a long-lasting remission period in steroid-dependent or frequently relapsing patients. Preliminary results support the use of RTX in patients with pure membranous LN and immunoglobulin-mediated membranoproliferative glomerulonephritis (MPGN), but not in patients with class III/IV LN or complement-mediated MPGN. No conclusion can be drawn in idiopathic focal segmental glomerulosclerosis (FSGS) and anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN) because studies are small, heterogeneous, and scarce. Lastly, immunosuppression including RTX is not particularly useful in IgA nephropathy. This review presents the general background, outcomes, and safety for RTX treatment in different glomerulopathies. In this regard, we describe randomized controlled trials (RCTs) performed in adults, whenever possible. A literature search was performed using clinicaltrials.gov and PubMed.

Rituximab therapy in adults with steroid-dependent nephrotic syndrome

INTRODUCTION

Patients with steroid-dependent nephrotic syndrome (SDNS) suffer frequent relapse with adverse effects caused by long-term prednisolone treatment. Recently, the chimeric monoclonal antibody against the protein CD20 (rituximab - RTX) was observed to be efficacious and safe in the treatment of patients with SDNS. We summarized the scientific literature to evaluate RTX therapy in the clinical management of SDNS.

MATERIAL AND METHODS

PubMed, EMBASE, and Cochrane Library databases were investigated from interception to 2019-6-6, without language limitation. The analysis was restricted to adults ≥ 19 years of age. Data were administered and analyzed through the Review manager 5.3 software.

RESULTS

After RTX treatment, relapse times, prednisolone dose, and proteinuria decreased, whereas serum albumin was increased. The clinical parameters blood pressure and total cholesterol diminished also, whereas bone mineral density was improved. Overall, RTX ameliorated the adverse effects of prednisolone. Moreover, the Th1/Th2 ratio was changed except for the CD19 and CD20 cell counts. Additionally, most of the adverse effects of RTX were mild and well tolerated.

CONCLUSIONS

In the studies that we considered, we concluded that RTX treatment was effective and safe in the therapy of patients with SDNS. Nevertheless, more randomized controlled trials are required to explore the mechanism of RTX action and verify its efficacy.

Late-Onset Neutropenia after Rituximab Treatment for Adult-Onset Nephrotic Syndrome

A 41-year-old woman developed nephrotic syndrome at the age of 32 and was diagnosed with minimal change nephrotic syndrome based on a renal biopsy. Although remission was achieved with administration of prednisolone (PSL) and cyclosporine, the nephrotic syndrome recurred. She was also started on rituximab (RTX). She developed late-onset neutropenia after RTX treatment (R-LON) and improved 17 days later. Although the majority of R-LON cases undergo spontaneous remission, cases of death have been reported. This report is intended to warn about R-LON, since the use of RTX for adult-onset nephrotic syndrome is expected to increase in the future.

Comparison of the response of frequently relapsing steroid-dependent minimal change nephrotic syndrome to rituximab therapy between childhood-onset and adult-onset disease

Rituximab has been approved in Japan for the treatment of intractable nephrotic syndrome, but in cases of childhood-onset disease only; its efficacy and safety in adult-onset disease has yet to be established. This study was undertaken to evaluate the efficacy of rituximab and adverse effects in patients with adult-onset minimal change nephrotic syndrome (MCNS).The study involved 32 childhood-onset cases (mean age at onset: 8.6 years) and 19 adult-onset cases (mean age at onset: 30.6 years) of frequently relapsing steroid-dependent MCNS, all of whom received intravenous rituximab drip infusion (375 mg/m body surface area per dose) at 4 time points at 6-month intervals. Relapse frequency, oral dose of immunosuppressants, and adverse effects were compared between the 2 groups.Remission was maintained in all cases in the childhood-onset and adult-onset groups; a significant reduction in relapse frequency was noted during the first 24 months of rituximab therapy (0.3 ± 0.7 times and 0.3 ± 0.6 times in the childhood-onset and adult-onset groups, respectively; P < .001). Oral corticosteroid therapy could be discontinued in 81.3% of cases of the childhood-onset group (26/32 cases) and in 70.6% of cases of the adult-onset group (12/17 cases); the oral corticosteroid dose was reduced significantly to 0.9 ± 2.5 mg/day in the childhood-onset group and to 0.8 ± 1.6 mg/day in the adult-onset group (P < .001). Cyclosporin treatment was also discontinued in 87.5% of cases in the childhood-onset group (21/24 cases) and in 80.0% of cases of the adult-onset group (15/21 cases); the oral cyclosporin dose was reduced significantly to 8.6 ± 27.4 mg/day and 9.2 ± 22.0 mg/day, respectively (P < .001). Regarding adverse reactions, infusion reactions developed at a frequency of 21.1% and 19.7% in both groups, respectively, with no significant inter-group difference (P = .72).Rituximab showed significant efficacy in adult-onset MCNS, with a comparable incidence of adverse reactions to that in childhood-onset cases, suggesting that this drug can also be used safely in adult-onset MCNS.

Therapeutic efficacy of rituximab for the management of adult-onset steroid-dependent nephrotic syndrome: a retrospective study

BACKGROUND

Recent reports have described the efficacy of rituximab in treating steroid-dependent nephrotic syndrome (SDNS) in pediatric patients. However, few reports describe data regarding adult-onset SDNS. We investigated the efficacy of rituximab for the management of adult-onset SDNS.

METHODS

We performed a retrospective cohort study investigating eight patients with adult-onset SDNS who were treated with rituximab. Clinical data were obtained at the initiation of rituximab therapy. The primary outcomes evaluated were successful suppression of relapses and CD19+ cells after rituximab treatment. The corticosteroid- and immunosuppressant-sparing effect and adverse events were additionally evaluated.

RESULTS

All eight patients were diagnosed with minimal change nephrotic syndrome and received immunosuppressants in addition to corticosteroid. Total number of relapses was 10.5 times as a median value. Rituximab administration was repeated in two patients, whereas six received single-dose rituximab. Three of eight (37.5%) patients showed relapse after rituximab therapy. A rituximab-induced depletion in CD19+ cells noted initially was followed by their reappearance in all patients. There were cases with no relapse after the reappearance of CD19+ cells. The median relapse time pre- and post-rituximab therapy showed a decrease from 1 time/year (interquartile range [IQR] 1-3 times/year) to 0 time/year (IQR 0-1 time/year). Rituximab treatment induced a significant reduction in the required doses of corticosteroid and cyclosporine (P < 0.01). No serious adverse events were observed.

CONCLUSION

Rituximab treatment was effective not only in childhood-onset but also in adult-onset SDNS. Further studies are needed to establish optimal treatment regimens.

Adult minimal-change disease: observational data from a UK centre on patient characteristics, therapies, and outcomes

Background

Minimal change disease (MCD) is a common cause of the nephrotic syndrome in adults with limited evidence on its treatment and prognosis. We examined the presenting characteristics, treatments, and outcomes of adult patients with MCD in our centre.

Methods

This was an observational cohort study using retrospectively-collected data. All patients who had a renal biopsy reported as MCD between 1996 and 2012 were included, and data were collected at baseline and during follow-up. Statistical analysis included Cox-regression analysis to examine which factors were associated with risk of relapse.

Results

Seventy-eight patients were included, and had a median age of 36 years, and were 60% male and 73% white. Median follow-up time was 72 months. 37% were in AKI at presentation, which was significantly associated with a lower serum albumin and older age. Although 10% were steroid-resistant, 98% achieved remission at a median time of 5 weeks. 61% relapsed, at a median time of 11 months, and patients had a median number of 2 relapses during follow-up. A higher eGFR was associated with an increased risk of relapse (hazard ratio 1.18 [1.03–1.36] per 10 mL/min increase in eGFR), and females were significantly more likely than males to have an early relapse. Nearly half of the cohort required an additional immunosuppressive agent on top of glucocorticoids, the most commonly used being calcineurin inhibitors. Five patients subsequently developed FSGS: these patients had a lower baseline creatinine, a higher serum albumin, a longer time to remission, and were more likely to be steroid-resistant. Follow-up renal function was generally preserved, but follow-up creatinine was higher in those who had presented with AKI, and in those who had been commenced on a RAS inhibitor after biopsy. Infection requiring admission, diabetes mellitus and venous thromboembolism developed in 14%, 12%, and 12% of patients respectively.

Conclusions

Nearly all adults with MCD achieve remission, but relapses and disease- and therapy-related complications are common. In our cohort, eGFR and gender were associated with risk of relapse, and these previously undescribed associations could be explored further in future work.

Rituximab treatment in adults with refractory minimal change disease or focal segmental glomerulosclerosis

Rituximab (RTX) may benefit patients with glomerular disease who suffer from focal segmental glomerular sclerosis (FSGS) or minimal change disease (MCD). Here, we have described our experience treating 6 FSGS and 9 MCD patients with steroid-dependent/refractory nephrotic syndrome (NS) with RTX. Patients received RTX (375 mg/m2) intravenously on days 1, 8, 23, and 29. During a median follow-up of 8 months (range, 3-36 months) after RTX administration, all patients achieved complete or partial remission. Relapses decreased by approximately 30-fold compared with the year preceding RTX treatment, and an 89.27% reduction in proteinuria was observed. Furthermore, RTX treatment could decrease medical costs by 76.52% compared with the costs associated with the long-term use (for 12-13 months) of steroids and immunosuppressive drugs. In conclusion, RTX treatment was safe and effective for patients with refractory FSGS or MCD.

Recent Treatment Advances and New Trials in Adult Nephrotic Syndrome

The etiology of nephrotic syndrome is complex and ranges from primary glomerulonephritis to secondary forms. Patients with nephrotic syndrome often need immunosuppressive treatment with its side effects and may progress to end stage renal disease. This review focuses on recent advances in the treatment of primary causes of nephrotic syndrome (idiopathic membranous nephropathy (iMN), minimal change disease (MCD), and focal segmental glomerulosclerosis (FSGS)) since the publication of the KDIGO guidelines in 2012. Current treatment recommendations are mostly based on randomized controlled trials (RCTs) in children, small RCTs, or case series in adults. Recently, only a few new RCTs have been published, such as the Gemritux trial evaluating rituximab treatment versus supportive antiproteinuric and antihypertensive therapy in iMN. Many RCTs are ongoing for iMN, MCD, and FSGS that will provide further information on the effectiveness of different treatment options for the causative disease. In addition to reviewing recent clinical studies, we provide insight into potential new targets for the treatment of nephrotic syndrome from recent basic science publications.

Cost-Effectiveness of Administering Rituximab for Steroid-Dependent Nephrotic Syndrome and Frequently Relapsing Nephrotic Syndrome: A Preliminary Study in Japan

With regard to the use of rituximab for patients with steroid-dependent nephrotic syndrome and frequently relapsing nephrotic syndrome, not only has the regimen not been clinically verified but also there is a lack of health economics evidence. Therefore, we conducted a prospective clinical study on 30 patients before (with steroids and immunosuppressants) and after introducing rituximab therapy. Relapse rates and total invoiced medical expenses were selected as the primary endpoints for treatment effectiveness and treatment costs, respectively. As secondary endpoints, cost-effectiveness was compared before and after administering rituximab in relation to previous pharmacotherapy. The observation period was 24 months before and after the initiation of rituximab. We showed that there was a statistically significant improvement in the relapse rate from a mean of 4.30 events before administration to a mean of 0.27 events after administration and that there was a significantly better prognosis in the cumulative avoidance of relapse rate by Kaplan–Meier analysis (p < 0.01). Finally, the total medical costs decreased from 2,923 USD to 1,280 USD per month, and the pre–post cost-effectiveness was confirmed as dominant. We, therefore, conclude that treatment with rituximab was possibly superior to previous pharmacological treatments from a health economics perspective.

Rituximab use in adult primary glomerulopathy: where is the evidence?

Rituximab is a chimeric anti-CD20 antibody that results in depletion of B-cell lymphocytes. It is currently used in the treatment of a variety of autoimmune diseases, in addition to CD20-positive lymphomas. The use of rituximab in the treatment of the adult primary glomerular diseases has emerged recently, although not yet established as first-line therapy in international guidelines. In patients with steroid-dependent minimal change disease or frequently relapsing disease, and in patients with idiopathic membranous nephropathy (IMN), several retrospective and prospective studies support the use of rituximab to induce remission, whereas in idiopathic focal and segmental glomerulosclerosis (FSGS), the use of rituximab has resulted in variable results. Evidence is still lacking for the use of rituximab in patients with immunoglobulin A nephropathy (IgAN) and idiopathic membranoproliferative glomerulonephritis (MPGN), as only few reports used rituximab in these two entities. Randomized controlled trials (RCTs) are warranted and clearly needed to establish the definitive role of rituximab in the management of steroid-dependent and frequently relapsing minimal change disease, IMN, both as first-line and second-line treatment, and in MPGN. We await the results of an ongoing RCT of rituximab use in IgAN. Although current evidence for the use of rituximab in patients with idiopathic FSGS is poor, more RCTs are needed to clarify its role, if any, in the management of steroid-resistant or steroid-dependent FSGS.

Anti-CD20 Antibodies for Idiopathic Nephrotic Syndrome in Children

Rituximab, a chimeric anti-CD20 monoclonal antibody originally licensed for lymphoma, is emerging as a novel steroid-sparing agent for idiopathic nephrotic syndrome in children. The potential use of anti-CD20 monoclonal antibodies in idiopathic nephrotic syndrome has contributed to shifting the view of podocytopathies from T cell-mediated to more complex immunomediated disorders that can benefit from targeting B cells and other mediators of the early immune response. Clinical data on the use of rituximab also have implications on disease management and classification. In this review, we present results of clinical studies that support rituximab as an effective steroid-sparing agent in steroid-dependent idiopathic nephrotic syndrome. Recent randomized controlled trials suggest that potential benefits of rituximab therapy in steroid-dependent forms of idiopathic nephrotic syndrome vary depending on whether children are dependent on steroids alone or on both steroids and calcineurin inhibitors, with greater probabilities to achieve drug-free remission in the former group. Multiple-drug dependence may identify a different disease state with different prognosis and treatment options. Insufficient data are available on optimal use of rituximab as a maintenance steroid-sparing agent in these steroid-sensitive forms of the disease, including how often and for how long rituximab infusions should be repeated to maximize expected benefits and minimize potential harms. Finally, one randomized controlled trial in children with steroid-resistant idiopathic nephrotic syndrome yielded negative results. New anti-CD20 antibodies are under study in this patient population.