The efficacy and safety of rituximab in treating childhood refractory nephrotic syndrome: a meta-analysis

Nephrotic Syndrome: A Review

Nephrotic syndrome (NS) is characterized by hypoalbuminemia, severe proteinuria, and peripheral edema, frequently in conjunction with hyperlipidemia. Individuals usually show symptoms of weariness and swelling, but no signs of serious liver damage or cardiac failure. With characteristic medical symptoms and evidence of hypoalbuminemia and severe proteinuria, NS can be diagnosed. The majority of NS episodes are classified as unexplained or primary; the most prevalent histopathological subgroups of primary NS in people are focal segmental glomerulosclerosis and membraneous nephropathy. Thrombosis of the veins with high cholesterol levels is a significant NS risk. Acute renal damage and infection are further possible side effects. The pathobiochemistry of NS involves alterations in genes that affect the selectivity of the kidneys and abnormalities in proteins related to podocytes. Understanding the molecular mechanisms that influence these processes is crucial to developing specific and targeted therapeutic approaches. The need for invasive renal biopsies throughout the diagnosis process may be lessened by the development of non-invasive nephrotic syndrome biomarkers, such as microRNAs. Corticosteroids are frequently used as the initial line of defense in NS treatment. However, some individuals need other treatments since a resistant type of NS also exists. The use of calcineurin inhibitors, mycophenolate mofetil, and rituximab is mentioned in the text, along with current research to identify safer and more efficient therapeutic choices. The complicated kidney condition NS has several underlying causes and symptoms. For the diagnosis of this ailment as well as the creation of focused therapies, an understanding of the pathophysiology and the identification of possible biomarkers are essential.

Efficacy of rituximab therapy in children with nephrotic syndrome: a 10-year experience from an Iranian pediatric hospital

Background

There are controversy results in the optimal management of children with steroid-dependent and steroid-resistant nephrotic syndrome (SDNS, SRNS). This study aimed to determine the efficacy and safety of rituximab (RTX) in these pediatric patients.

Methods

Medical records of 1–18-year-old Iranian children with SDNS (n = 26) and SRNS (n = 22) with a follow-up for at least 24 months were included from 2009 to 2019. The short- and long-term responses to RTX were respectively evaluated to determine the random protein-to-creatinine ratio after 6 and 24 months and classified as complete (CR) and partial (PR) remission or no response.

Results

Male patients (n = 26) were slightly predominate. The median age of patients at the time of RTX therapy was 8.6 ± 4.01 years. At the end of the 6-month follow-up, CR and PR occurred in 23 (47.9%) and 12 (25%) patients, respectively. Of 23 patients with CR, 18 (69.2%) and 5(22.7%) had SDNS and SRNS, respectively (p < 0.005). However, only 18 (37.5%) of patients after 24 months had been in CR. No significant difference in the CR rate was found between the two groups. RTX was more effective when administered during the proteinuria-free period (p = 0.001).

Conclusion

In the short term, RTX significantly was efficient in inducing complete or PR in SDNS and SRNS patients. However, the favorable response rate in a long-term follow-up was insignificantly lower between the two groups.

Efficacy and safety of rituximab for childhood refractory nephrotic syndrome: A meta-analysis of randomized controlled trials

BACKGROUND

Idiopathic nephrotic syndrome is the most common glomerular disease in children, but there are still some difficulties in treating childhood steroid-dependent or steroid-resistant nephrotic syndrome (SDNS/SRNS). Rituximab (RTX) might be an effective and safe choice.

METHODS

Studies were searched from PubMed, Web of Science, Cochrane library and some Chinese databases up to April 2020. Only randomized controlled trials (RCT) were included.

RESULTS

Of 1383 screened articles, 6 RCTs with 334 participants were included. RTX was better than the control group at improving relapse-free rate in the short term [RR (risk ratio) (95% CI (confidence interval)), 1.84(1.41, 2.39)]. As for long-term, RTX did not show significant improvement [RR (95% CI), 4.43(.57, 34.67)]; but in subgroup analysis, RTX was still better than conventional drugs and tacrolimus [RR (95% CI), 9.91(1.95, 50.52) and 1.42(1.15, 1.75), respectively]. And there was a difference between the two groups of prednisolone dose after treatment [MD (mean difference) (95% CI), -.22(-.36, -.09) mg/kg/d)]. However, RTX did not significantly improve serum albumin and creatinine [MD (95% CI), 3.46(-1.40, 8.32)g/L and -3.66(-11.79, 4.48)μmol/L, respectively]. No significant differences between the RTX and the control group were found in total adverse events (AEs) or serious AEs.

CONCLUSION

Childhood SDNS/SRNS patients appear to benefit from RTX in relapse-free rate and dose of prednisolone use. Also, RTX did not significantly increase the incidence of AEs. But RTX did not show improvements in biological indicators, more studies are required to explain the effect of RTX.

Tetrandrine may treat membranous glomerulopathy via P13K/Akt signaling pathway regulation: therapeutic mechanism validation using Heymann nephritis rat model

Membranous glomerulopathy (MGN) is an autoimmune kidney disease that is the primary cause of nephrotic syndrome (NS) in adults. Tetrandrine, a bisbenzylisoquinoline alkaloid, is known to have numerous pharmacological effects. In this study, network pharmacology analysis and experimental validation were conducted to analyze the mechanisms by which tetrandrine functions as a therapeutic intervention for MGN. A systematic network pharmacology method was applied to identify potential targets and determine the therapeutic mechanism of tetrandrine in MGN treatment. A Heymann nephritis (HN) rat model was developed to assess the therapeutic effects of tetrandrine on NS and validate the predicted molecular mechanisms. We obtained 86 potential targets of tetrandrine for the treatment of NS. In vivo experiments showed that tetrandrine could reduce the 24-h urine protein content, decrease glomerular basement membrane proliferation, and significantly decrease thylakoid stroma and cell proliferation in the HN rat kidney tissue. Moreover, tetrandrine suppressed kidney cell apoptosis and upregulated the expression of nephrin and podocin in HN model rats. qRT-PCR results revealed that tetrandrine inhibited IL-1β, TNFα, and MCP-1 levels in HN model rats. Western blot results indicated that tetrandrine can protect against MGN via the PI3K/Akt signaling pathway. Thus, by using a combination of network and experimental pharmacology methods, we demonstrate that tetrandrine can treat MGN via the PI3K/Akt signaling pathway and provide novel insights into the mechanisms underlying tetrandrine-mediated management of MGN.

The efficacy of rituximab in the treatment of refractory nephrotic syndrome: a meta-analysis

OBJECTIVE

The evidence from epidemiological research on whether the efficacy of rituximab in treatment of refractory nephrotic syndrome (NS) is better than other agents is inconsistent. This meta-analysis aimed to assess the efficacy of rituximab in the treatment of NS compared with other immunosuppressive agents.

METHODS

Relevant literatures were identified and evaluated for quality before October 2019 through multiple search strategies on PubMed and EMBASE. Statistical evidence of the symmetry of the funnel plot obtained from Begg's test was indicated by Egger's linear regression and a sensitivity analysis identified heterogeneity. A fixed- or a random-effects model was applied to calculate the pooled SMDs and RRs.

RESULTS

A total of 12 studies, involving 383 patients and 354 controls, were included. Compared with other agents, rituximab significantly improved complete remission both in children and adults [Overall: RR = 1.313, 95% CI = 1.170-1.475, P < 0.001; Adult: RR = 1.359, 95% CI = 1.053-1.753, P = 0.019 Children: RR = 1.354, 95% CI = 1.072-1.709, P < 0.001], and dramatically decreased the relapse rate in children [Overall: RR = 0.349, 95% CI = 0.166-0.732, P < 0.001; Children: RR = 0.286, 95% CI = 0.176-0.463, P < 0.001].

CONCLUSIONS

Rituximab might be a promising treatment for refractory NS. Compared with other agents, rituximab significantly improves the complete remission and decreased the relapse rate. However, to confirm the efficacy of rituximab in the treatment of refractory NS, more high-quality, large sample, and multicenter randomized controlled trials are needed.

Efficacy and safety of rituximab in the treatment of membranous nephropathy: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Rituximab (RTX) is considered to be a promising drug for curing membranous nephropathy. However, the efficacy and safety of RTX in treating membranous nephropathy remain uncertain. This meta-analysis aimed to investigate the efficacy and safety of RTX in patients with membranous nephropathy.

METHODS

A literature search was performed using Pubmed, Embase, OVID, and Cochrane Library and randomized controlled trials (RCTs) case-controls and cohort studies published till 30 July 2019 were assessed. The studies assessing the efficacy and safety of RTX in patients with membranous nephropathy were included.

RESULTS

Eight relevant trials involving 542 patients were included in the meta-analysis. It was found that RTX did not significantly improve serum albumin levels and e-GFR when compared with the control group (including cyclosporine and cyclophosphamide, chlorambucil, prednisone, non-immunosuppressive anti-proteinuria treatment), serum albumin levels (OR = 0.31, 95%CI-0.12-0.74, P = .15), e-GFR (OR = -1.49, 95%CI-17.14-14.17, P = .85). However, RTX did reduce the serum creatinine (OR = -0.01, 95%CI-0.36-0.34, P = .95) and urinary protein (OR = -2.39, 95%CI -7.30 -2.53, P = .34) levels. Also, in comparison to the control group, RTX did improve the total remission rate (OR = 1.63, 95%CI 0.48-5.54, P = .43), achieve a higher rate of complete remission (OR = 2.54, 95%CI 1.65-3.90, P < .01) and also reduced the amount of M-type phospholipase A2 receptor-Antibody depletion in patients (OR = 5.59, 95%CI 1.81-17.2, P = .003). RTX-related adverse events were mostly mild (most infusion-related reactions) in nature and serious adverse events were rare.

CONCLUSION

RTX proved to be efficient, well-tolerated and a safe drug in the treatment of membranous nephropathy. Most patients reach complete remission during the follow-up period, and relapse is rare. RTX may turn out to be promising in membranous nephropathy patients.

Relationships between the clinical phenotypes and genetic variants associated with the immunological mechanism in childhood idiopathic nephrotic syndrome: protocol for a prospective observational single-centre cohort study

INTRODUCTION

Idiopathic nephrotic syndrome (INS) is the most common glomerulopathy that results in childhood chronic kidney disease in China, but the relationships between different clinical phenotypes and immunological genetic variants observed in patients with INS are ambiguous and have not been well studied. A cohort study combined with whole exome sequencing might further identify the effects of immunological genetic variants on clinical phenotypes and treatment outcomes.

METHODS AND ANALYSIS

We describe a 3 year prospective observational single-centre cohort study to be conducted in the Children's Hospital of Chongqing Medical University in China. This study will recruit and investigate 336 patients with childhood-onset INS presenting with different clinical phenotypes. Whole exome sequencing will be conducted when patients progress to a confirmed clinical phenotype during follow-up. Relevant clinical and epidemiological data, as well as conventional specimens, will be collected at study entry and 1 month, 3 months, 6 months, 1 year, 2 years and 3 years after disease onset. After this cohort is generated, the immunological genetic variants of steroid-sensitive nephrotic syndrome without frequent relapse, steroid-resistant nephrotic syndrome and steroid-dependent/frequent relapse nephrotic syndrome will be evaluated.

ETHICS AND DISSEMINATION

The study protocol is approved by Ethics Committee of Children's Hospital of Chongqing Medical University (reference number 2018-140). The results will be disseminated through peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

ChiCTR1800019795.

Efficacy and acceptability of immunosuppressive agents for pediatric frequently-relapsing and steroid-dependent nephrotic syndrome: A network meta-analysis of randomized controlled trials

INTRODUCTION

A network meta-analysis was conducted to regard the effects of available immunosuppressive medications in pediatric frequently-relapsing nephrotic syndrome (FRNS) and steroid-dependent nephrotic syndrome (SDNS).

METHODS

We reviewed systematically 26 randomized controlled trials (1311 patients) that compared any of the following immunosuppressive agents to placebo/nontreatment (P/NT) or another drug for FRNS/SDNS treatment in children.

RESULTS

The main outcomes were efficacy and acceptability. At the 6-month, cyclophosphamide, chlorambucil, levamisole, and rituximab had better efficacy than P/NT (odds ratio [OR]: 0.09, 0.03, 0.28, and 0.07, respectively); cyclophosphamide was significantly more effective than azathioprine and chlorambucil. At 12 months, cyclophosphamide, chlorambucil, cyclosporine, levamisole, and rituximab had better efficacy than P/NT (0.10, 0.03, 0.10, 0.23, and 0.07, respectively); Chlorambucil were found to be more efficacious than levamisole and MMF (0.12 and 0.09, respectively). At 24 months, cyclophosphamide, chlorambucil, and levamisole had better efficacy than P/NT (0.09, 0.04, and 0.03, respectively); cyclophosphamide had better efficacy than cyclosporine and vincristine (0.17 and 0.39, respectively).

CONCLUSION

No significant differences in acceptability were found. Our results suggest that cyclophosphamide may be preferred initially in children with FRSN/SDNS, chlorambucil, and rituximab may be acceptable medications for patients with FRSN/SDNS. Long-term follow-up trials focused on gonadal toxicity and limitation of maximum dosage of cyclophosphamide should been carried out.

Low-dose rituximab is no less effective for nephrotic syndrome measured by 12-month outcome

OBJECTIVE

Rituximab is an effective treatment for children with steroid dependent or frequently relapsing nephrotic syndrome. The optimum dosing schedule for rituximab has not been established. We hypothesized that a single low dose of 375 mg/m² would have comparable outcomes to higher doses in reducing the frequency of relapse and time to B cell reconstitution.

METHODS

We conducted a multicenter retrospective observational cohort study of children with steroid-sensitive frequently relapsing nephrotic syndrome. Data were extracted from clinical records including the dates of diagnosis, treatment, relapses, the use of concomitant immunosuppression, and lymphocyte subset profiling. Patients treated earlier received variable doses of rituximab, although typically two doses of 750 mg/m². Later, patients received the current regimen of a single dose of 375 mg/m². The primary outcome was an absence of clinically confirmed relapse 12 months following rituximab administration. Secondary outcomes were median time to relapse, probability of being relapse-free at 6 and 24 months and time to reconstitution of CD19⁺ B cells.

RESULTS

Sixty patients received 143 courses of rituximab. Seven different dosing regimen strategies were used, ranging between 375 and 750 mg/m² per dose, with administration of 1-4 doses. There was no significant difference in event-free survival at 12 months between dosing strategies. The median time to reconstitution of B cells was not significantly different between groups.

CONCLUSIONS

Use of a single low-dose regimen of rituximab in the management of frequently relapsing nephrotic syndrome does not affect the probability of relapse at 12 months or time to B cell reconstitution compared to a conventional higher dose.

Cost analysis on the use of rituximab and calcineurin inhibitors in children and adolescents with steroid-dependent nephrotic syndrome

BACKGROUND

Rituximab (RTX) is increasingly being used in place of calcineurin inhibitors (CNI) in pediatric patients with steroid-dependent nephrotic syndrome (SDNS). However, despite its favorable safety profile, its unit cost is prohibitive. We therefore compared the healthcare costs associated with the use of both agents in a retrospective cohort.

METHODS

This study was a retrospective analysis of data retrieved from the medical charts and electronic databases of pediatric patients (age range 2-18 years) with SDNS who were treated with either CNI or RTX from January 2008 to December 2012 at Children's Hospital of New Orleans, Louisiana. The minimum follow-up period was 12 months.

RESULTS

Of the 18 patients whose medical data were analyzed, ten received RTX and eight were treated with CNI. The annualized healthcare cost for the rituximab group was $197,031 versus $189,857 (all values in US dollars) for the CNI group (p > 0.05). At the 12-month follow-up, more patients in the RTX group were in remission (40 vs. 25%). Duration of freedom from steroid use was longer in the RTX group, while body mass index was higher in the CNI arm (p > 0.05). No significant adverse events occurred in either group.

CONCLUSION

The expenditure for the RTX and CNI groups was comparable, but there were fewer clinical encounters in the former group, potentially reducing the burden of healthcare on the patient's family.

Single, very low rituximab doses in healthy volunteers - a pilot and a randomized trial: implications for dosing and biosimilarity testing

There are no  dose-finding trials available for rituximab that could guide dosing in non-malignant diseases. We hypothesized that currently used doses (≥375 mg/m2) exceed several hundred-fold the half-maximal effective dose, which is most sensitive for detecting putative differences between biosimilars and important for dose finding. In an open label, exploratory trial healthy volunteers received single infusions of rituximab at doses of 0.1, 0.3 or 1.0 mg/m2. Subsequently, in a double-blind, randomized trial healthy volunteers received single infusions of two rituximab products at doses of 0.1 and 0.3 mg/m2. In the exploratory trial rituximab transiently depleted CD20+ cells by a mean 68% (range: 57-95%), 74% (55-82%) and 97% (94-100%) immediately after the infusion of 0.1 (n = 4), 0.3 (n = 4) and 1 mg/m2 (n = 8), respectively. In the randomized trial CD20+ cells decreased by a mean 48% (25-84%) - 55% (26-85%) and 81 (67-89%) - 87% (77-96%) after infusion of 0.1 mg/m2 (n = 12) or 0.3 mg/m2 (n = 8 proposed biosimilar, n = 4 reference product) of the proposed biosimilar or the reference product, respectively. It is important to understand that in healthy volunteers <1% of the authorized rituximab doses depletes almost all circulating B lymphocytes. Thus, for non-malignant diseases alternative, more cost-effective dosing regimens seem plausible, but require clinical testing. (EudraCT-No. 2010-023781-45; EudraCT-No. 2013-001077-24).

Traditional Chinese Medicine for Refractory Nephrotic Syndrome: Strategies and Promising Treatments

Refractory nephrotic syndrome (RNS) is an immune-related kidney disease with poor clinical outcomes. Standard treatments include corticosteroids as the initial therapy and other immunosuppressants as second-line options. A substantial proportion of patients with RNS are resistant to or dependent on immunosuppressive drugs and often experience unremitting edema and proteinuria, cycles of remission and relapse, and/or serious adverse events due to long-term immunosuppression. Traditional Chinese medicine has a long history of treating complicated kidney diseases and holds great potential for providing effective treatments for RNS. This review describes the Chinese medical theories relating to the pathogenesis of RNS and discusses the strategies and treatment options using Chinese herbal medicine. Available preclinical and clinical evidence strongly supports the integration of traditional Chinese medicine and Western medicine for improving the outcome of RNS. Herbal medicine such as Astragalus membranaceus, Stephania tetrandra S. Moore, and Tripterygium wilfordii Hook F can serve as the alternative therapy when patients fail to respond to immunosuppression or as the complementary therapy to improve therapeutic efficacy and reduce side effects of immunosuppressive agents. Wuzhi capsules (Schisandra sphenanthera extract) with tacrolimus and tetrandrine with corticosteroids are two herb-drug combinations that have shown great promise and warrant further studies.

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.

Cyclosporine in the treatment of childhood idiopathic steroid resistant nephrotic syndrome: a single centre experience in Nigeria

Introduction

Children with steroid resistant nephrotic syndrome usually require treatment with second-line agents and calcineurin inhibitors such as cyclosporine are now recommended as initial therapy. These agents only recently become available in our environment and their impact on care is unknown. We reviewed the short-term treatment outcomes of their use in comparison with previous outcomes.

Methods

Medical records of children managed for idiopathic steroid resistant nephrotic syndrome over a 5 year period were reviewed. Remission rates and improvement in renal function following use of various agents were compared.

Results

Of 103 children with idiopathic nephrotic syndrome, 25(24.3%) were steroid resistant, of whom 17 received additional medications. Full remission rate for cyclosporine was 70% (7/10). Remission rates prior to the availability of cyclosporine were 40% (2/5) for cyclophosphamide and 66% (2/3), (partial remission only) with enalapril, an angiotensin converting enzyme inhibitor used in combination with alternate day prednisolone. One child with cyclophosphamide resistance subsequently achieved remission with cyclosporine. Remission was not related to sex (p=0.96), age (p=0.54), serum albumin (p=0.37) or hypertension (p=0.43) but to serum cholesterol (p= 0.02). The estimated glomerular filteration rate (eGFR) among children treated with cyclosporine ranged from 30-167 ml/min/1.73m² as follows: >90 (5); 60-89 (3); 30-59 (2) while the mean pre and post treatment eGFR in those with eGFR <90 were 60 and 104ml/min/1.73m² respectively (p=0.03). Mortality rate was 10% (1/10) in children treated with cyclosporine compared with 28.6% (2/7) in those treated with other medications (p=0.54).

Conclusion

Cyclosporine resulted in improved treatment outcomes in children with idiopathic steroid resistant nephrotic syndrome.

Rituximab shows no effect on remission in patients with refractory nephrotic syndrome: A MOOSE-compliant meta-analysis

To assess the efficacy of rituximab in treatment of refractory nephrotic syndrome (NS) compared with other agents.Studies were searched from Web of Science, PubMed, and CNKI up to April 2016. The standardized mean difference or relative risk or odds ratio and 95% confidence intervals were used to assess the efficacy of rituximab treatment compared with other agents in refractory NS.Totally, 8 studies were included. The present study showed that there was a significant higher relapse-free survival rate in rituximab group than that in the other agents group. Compared with other agents, rituximab did not significantly improve the complete and overall remission rate, serum albumin levels. Rituximab also did not decrease the serum creatinine, urinary protein, and serum cholesterol levels. However, compared with other agents, the adult patients had a higher serum cholesterol levels after treatment with rituximab.Rituximab promised to be a new agent in the treatment of refractory NS; it also could be used as an alternative to conventional immunosuppressive drugs-dependent or drugs-resistant. However, more high-quality, large sample, and multicenter randomized controlled trials are needed to further confirm the efficacy of rituximab in treatment of refractory NS.

Podocyte-actin dynamics in health and disease

Genetic studies of hereditary forms of nephrotic syndrome have identified several proteins that are involved in regulating the permselective properties of the glomerular filtration system. Further extensive research has elucidated the complex molecular basis of the glomerular filtration barrier and clearly established the pivotal role of podocytes in the pathophysiology of glomerular diseases. Podocyte architecture is centred on focal adhesions and slit diaphragms - multiprotein signalling hubs that regulate cell morphology and function. A highly interconnected actin cytoskeleton enables podocytes to adapt in order to accommodate environmental changes and maintain an intact glomerular filtration barrier. Actin-based endocytosis has now emerged as a regulator of podocyte integrity, providing an impetus for understanding the precise mechanisms that underlie the steady-state control of focal adhesion and slit diaphragm components. This Review outlines the role of actin dynamics and endocytosis in podocyte biology, and discusses how molecular heterogeneity in glomerular disorders could be exploited to deliver more rational therapeutic interventions, paving the way for targeted medicine in nephrology.

Comparison of second-line immunosuppressants for childhood refractory nephrotic syndrome: a systematic review and network meta-analysis

Although, most patients respond initially to therapy for nephrotic syndrome, about 70% of patients have a relapse. Currently, there is no consensus about the most appropriate second-line agent in children who continue to suffer a relapse. This network meta-analysis was designed to compare the efficacy and safety of the commonly used immunosuppressive agents in second-line therapeutic agents (ie, cyclophosphamide, cyclosporine, tacrolimus and mycophenolate mofetil) for refractory childhood nephrotic syndrome. MEDLINE, Cochrane, EMBASE and Google Scholar databases were searched until October 17, 2015 using the following search terms: cyclophosphamide, cyclosporine, tacrolimus, mycophenolate mofetil and childhood nephrotic syndrome. Randomized controlled trials, prospective 2-arm studies and cohort studies were included. 7 studies with 391 patients were included. Bayesian network meta-analysis found that treatment with mycophenolate mofetil had the greatest odds of relapse compared with tacrolimus (pooled OR=49.72, 95% credibility interval (CrI) 1.65 to 2483.32), cyclophosphamide (pooled OR=72.05, 95% CrI 1.44 to 13633.33) and cyclosporine (pooled OR=11.42, 95% CrI 1.03 to 131.60). Rank probability analysis found cyclophosphamide was the best treatment with the lowest relapse rate as compared with other treatments (rank probability=0.58), and tacrolimus was ranked as the second best (rank probability=0.38). Our findings support the use of cyclophosphamide and tacrolimus in treating children with relapsing nephrotic syndrome.

The efficacy and safety of rituximab in treating childhood nephrotic syndrome: an Italian perspective

BACKGROUND

Nephrotic syndrome is a disorder characterized by proteinuria, hypoalbuminemia and dyslipidemia. Low-dose alternate-day steroid regimen is the standard of care. In case of relapse or significant adverse events, steroid-sparing agents may be used. This analysis was aimed at assessing the efficacy and safety of rituximab for the treatment of children with nephrotic syndrome.

RESULTS

Four studies were included in the final meta-analysis. The end-point of our analysis was the percentage of patients in remission at 6 months. Pooled data from the four studies favours the use of rituximab (RR 5.25, 95 % CI: 3.05-9.06; p < 0.0001). As regards the safety data, rituximab has a limited number of adverse effects, the most common of which occur during the infusions.

CONCLUSIONS

In Italy, the off-label use of drugs is regulated by Law 648/96. In our opinion, there are three scientific requirements to merit a conditional national reimbursement for rituximab in nephrotic syndrome: 1. favourable clinical efficacy and safety data; 2. no available alternatives; 3. outcome data collecting by AIFA through prescribers. In conclusion, our results report a significant incremental benefit of adding rituximab to corticosteroid and/or calcineurin inhibitors for the treatment of nephrotic syndrome.

Pathogenesis of minimal change nephrotic syndrome: an immunological concept

Idiopathic nephrotic syndrome (INS) in children is characterized by massive proteinuria and hypoalbuminemia. Minimal change nephrotic syndrome (MCNS) is the most common form of INS in children. The pathogenesis of MCNS still remains unclear, however, several hypotheses have been recently proposed. For several decades, MCNS has been considered a T-cell disorder, which causes the impairment of the glomerular filtration barrier with the release of different circulating factors. Increased levels of several cytokines are also suggested. Recently, a "two-hit" theory was proposed that included the induction of CD80 (B7-1) and regulatory T-cell (Treg) dysfunction, with or without impaired autoregulatory functions of the podocyte. In contrast to the well-established involvement of T cells, the role of B cells has not been clearly identified. However, B-cell biology has recently gained more attention, because rituximab (a monoclonal antibody directed against CD20-bearing cells) demonstrated a very good therapeutic response in the treatment of childhood and adult MCNS. Here, we discuss recent insights into the pathogenesis of MCNS in children.