A multicenter trial of mizoribine compared with placebo in children with frequently relapsing nephrotic syndrome

Non-corticosteroid immunosuppressive medications for steroid-sensitive nephrotic syndrome in children

BACKGROUND

About 80% of children with steroid-sensitive nephrotic syndrome (SSNS) have relapses. Of these children, half will relapse frequently, and are at risk of adverse effects from corticosteroids. While non-corticosteroid immunosuppressive medications prolong periods of remission, they have significant potential adverse effects. Currently, there is no consensus about the most appropriate second-line agent in children with frequently relapsing SSNS. In addition, these medications could be used with corticosteroids in the initial episode of SSNS to prolong the period of remission. This is the fifth update of a review first published in 2001 and updated in 2005, 2008, 2013 and 2020.

OBJECTIVES

To evaluate the benefits and harms of non-corticosteroid immunosuppressive medications in SSNS in children with a relapsing course of SSNS and in children with their first episode of nephrotic syndrome.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to October 2024 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs were included if they involved children with SSNS and compared non-corticosteroid immunosuppressive medications with placebo, corticosteroids or no treatment; different non-corticosteroid immunosuppressive medications, or different doses, durations or routes of administration of the same non-corticosteroid immunosuppressive medication.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility, risk of bias and extracted data from the included studies. Statistical analyses were performed using a random-effects model and results expressed as risk ratio (RR) for dichotomous outcomes or mean difference (MD) for continuous outcomes with 95% confidence intervals (CI). Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We identified 58 studies (122 reports) randomising 3720 children. Half were multicentre studies, and most studies were undertaken in South and East Asia (28 studies) and Europe (20 studies). The numbers of children randomised ranged from 14 to 211. Risk of bias assessment indicated that 32 and 33 studies were at low risk of bias for sequence generation and allocation concealment, respectively. Eleven studies were at low risk of performance bias and 13 were at low risk of detection bias. Forty-eight and 36 studies were at low risk of incomplete and selective reporting, respectively. Rituximab with or without prednisone compared with placebo with or without prednisone probably reduces the number of children experiencing relapse at six months (5 studies, 182 children: RR 0.22, 95% CI 0.11 to 0.43) and 12 months (3 studies, 108 children: RR 0.38, 95% CI 0.13 to 1.09) (moderate certainty), may increase the number with severe infusion reactions (4 studies, 162 children: RR 5.21, 95% CI 1.19 to 22.89; low certainty), but not severe infection or arthropathy (low certainty). Rituximab compared with tacrolimus probably reduces the risk of relapse at 12 months (4 studies, 238 children: RR 0.64, 95% CI 0.42 to 0.96) and may reduce the risk of relapse when compared with low dose mycophenolate mofetil (MMF) (1 study, 30 children: RR 0.17, 95% CI 0.04 to 0.62). Rituximab followed by MMF for 500 days reduces the risk of relapse compared with rituximab followed by placebo for 500 days (1 study, 78 children: RR 0.29, 95% CI 0.13 to 0.63; high certainty). Rituximab probably does not differ from ofatumumab in the riisk of relapse and 12 months (1 study, 140 children: RR 1.03, 95% CI 0.75 to 1.41; moderate certainty) or in adverse events. MMF and levamisole (1 study, 149 children: RR 0.90, 95% CI 0.70 to 1.16) may have similar effects on the number of children who relapse at 12 months (low certainty). Cyclosporin compared with MMF may reduce the risk of relapse at 12 months (3 studies, 114 children: RR 1.57, 95% CI 1.08 to 2.30) (low certainty). Levamisole compared with steroids or placebo may reduce the number of children with relapse during treatment (8 studies, 474 children: RR 0.52, 95% CI 0.33 to 0.82) (low certainty). Preliminary data from single studies indicate that levamisole and prednisone compared with prednisone alone may delay the onset of relapse after the initial episode of SSNS and that levamisole compared with increasing prednisone administration from alternate day to daily at the onset of infection may reduce the risk of relapse with infection (low certainty). Cyclosporin compared with prednisone may reduce the number of children who relapse (1 study, 104 children: RR 0.33, 95% CI 0.13 to 0.83) (low certainty). Alkylating agents compared with cyclosporin may make little or no difference to the risk of relapse during cyclosporin treatment (2 studies, 95 children: RR 0.91, 95% CI 0.55 to 1.48) (low certainty evidence) but may reduce the risk of relapse at 12 to 24 months (2 studies, 95 children: RR 0.51, 95% CI 0.35 to 0.74) (low certainty). Alkylating agents (cyclophosphamide and chlorambucil) compared with prednisone probably reduce the number of children who experience relapse at six to 12 months (6 studies, 202 children: RR 0.44, 95% CI 0.32 to 0.60) and at 12 to 24 months (4 studies, 59 children: RR 0.20, 95% CI 0.09 to 0.46) (moderate certainty).

AUTHORS' CONCLUSIONS

New studies incorporated in this review update indicate that rituximab compared with prednisone, tacrolimus, or MMF is a valuable additional agent for managing children with relapsing SSNS. Comparative studies of CNIs, MMF, and levamisole suggest that CNIs may be more effective than MMF and that levamisole may be similar in efficacy to MMF. Important new studies suggest that MMF prolongs remission following rituximab, that levamisole may prevent infection-related relapse more effectively than changing from alternate-day to daily prednisone and that levamisole and prednisone compared with prednisone alone may prolong the time to first relapse. There are currently 23 ongoing studies which should improve our understanding of how to treat children with frequently relapsing SSNS.

Novel approaches to primary membranous nephropathy: Beyond the KDIGO guidelines

Primary membranous nephropathy (PMN) is an immune-mediated glomerular disease. Rituximab (RTX) is recommended as a first-line immunosuppressive therapy and shows high clinical efficacy, but the optimal doses remain controversial. Approximately 20%-40% of PMN patients experience RTX resistance and failure. Reduced bioavailability, RTX internalization and attack, anti-RTX antibody production, autoreactive B-cell reservoirs and chronic and irreversible renal damage may contribute to this problem. Therefore, new treatment modalities are needed to compensate for this deficit. New interventions and new dose combinations are being proposed. Multiple drug combination therapies show comparable clinical efficacy to conventional treatments by blocking the production of disease-causing antibodies in multiple directions, and can reduce single-agent doses without increasing adverse effects. New therapies that directly target B cells, plasma cells, and antibody production have shown encouraging results. In addition, new techniques for sweeping antibodies and chimeric antigen receptor T-cell therapy also may be promising strategies for PMN. Immunoadsorption could be used as an auxiliary choice for severe cases. This article explores new treatments for PMN and highlights possible mechanisms for potential new technologies that offer new ideas for treatment.

Immunosuppressive Agent Options for Primary Nephrotic Syndrome: A Review of Network Meta-Analyses and Cost-Effectiveness Analysis

Therapeutic options with immunosuppressive agents for glomerular diseases have widened with refinements to the Kidney Disease Improving Global Outcomes (KDIGO) guidelines from 2012 to 2021. However, international guidelines do not necessarily match the reality in each country. Expensive therapies such as rituximab and calcineurin inhibitors are sometimes inaccessible to patients with refractory nephrotic syndrome due to cost or regulations. Under the Japanese medical insurance system, rituximab is accessible but still limited to steroid-dependent patients who developed idiopathic nephrotic syndrome in childhood. Based on international KDIGO guidelines and other national guidelines, possible applications of immunosuppressive agents for nephrotic syndrome are comprehensively examined in this review. While rituximab has become the mainstay of immunosuppressive therapy for nephrotic syndrome, clinical trials have indicated that options such as cyclophosphamide, calcineurin inhibitors, and mycophenolate mofetil would be preferable. Given the rising number of patients with nephrotic syndrome worldwide, KDIGO guidelines mention the need for further consideration of cost-effectiveness. If the new option of rituximab is to be the first choice in combination with steroids for nephrotic syndrome, its cost-effectiveness should also be verified. Among the few studies examining the cost-effectiveness of treatments for nephrotic syndrome, administration of rituximab to young adults has been shown to be cost-beneficial, at least in Japan. However, further large-scale studies involving multiple facilities are needed to verify such findings. Network meta-analyses have concluded that the efficacy of rituximab remains controversial and confirmation through high-quality studies of large cohorts is needed. To this end, the mechanisms of action underlying immunosuppressive agents, both old and new, need to be understood and experience must be accumulated to evaluate possible effects and side effects.

Mizoribine combined with steroids and dietary sodium restriction on the treatment of primary membranous nephropathy: a prospective study

BACKGROUND

We aimed to initially explore the efficiency and safety of mizoribine (MZR) combined with steroids and dietary sodium restriction on the treatment of primary membranous nephropathy (MN) compared with cyclophosphamide (CPM)-based steroids.

METHODS

Patients with primary MN were enrolled. According to the therapy, they were divided into the MZR combined with steroids and dietary sodium restriction group (N = 30) and CPM-based steroids group (N = 30). Both groups were followed up for 1 year to monitor safety and efficacy.

RESULTS

Compared with the CPM-based steroids group, the MZR combined with steroids and dietary sodium restriction group had significantly lower daily sodium intake, serum sodium, blood pressure (BP), and 24 h urine protein (all P < 0.05). Conversely, plasma albumin and complete remission rate in the MZR group were higher at the 12th follow-up (40.39 ± 5.14 g/L vs. 37.63 ± 5.40 g/L; 86.67% vs. 66.67%; all P < 0.05). These two groups showed similar adverse events rates (20.00% vs. 26.67%, P = 0.54).

CONCLUSION

This study demonstrates that MZR combined with steroids and dietary sodium restriction is superior to CPM-based steroids in terms of complete remission and 24 h urine protein in patients with primary MN.

IPNA clinical practice recommendations for the diagnosis and management of children with steroid-sensitive nephrotic syndrome

Idiopathic nephrotic syndrome is the most frequent pediatric glomerular disease, affecting from 1.15 to 16.9 per 100,000 children per year globally. It is characterized by massive proteinuria, hypoalbuminemia, and/or concomitant edema. Approximately 85-90% of patients attain complete remission of proteinuria within 4-6 weeks of treatment with glucocorticoids, and therefore, have steroid-sensitive nephrotic syndrome (SSNS). Among those patients who are steroid sensitive, 70-80% will have at least one relapse during follow-up, and up to 50% of these patients will experience frequent relapses or become dependent on glucocorticoids to maintain remission. The dose and duration of steroid treatment to prolong time between relapses remains a subject of much debate, and patients continue to experience a high prevalence of steroid-related morbidity. Various steroid-sparing immunosuppressive drugs have been used in clinical practice; however, there is marked practice variation in the selection of these drugs and timing of their introduction during the course of the disease. Therefore, international evidence-based clinical practice recommendations (CPRs) are needed to guide clinical practice and reduce practice variation. The International Pediatric Nephrology Association (IPNA) convened a team of experts including pediatric nephrologists, an adult nephrologist, and a patient representative to develop comprehensive CPRs on the diagnosis and management of SSNS in children. After performing a systematic literature review on 12 clinically relevant PICO (Patient or Population covered, Intervention, Comparator, Outcome) questions, recommendations were formulated and formally graded at several virtual consensus meetings. New definitions for treatment outcomes to help guide change of therapy and recommendations for important research questions are given.

Fanconi syndrome in an elderly patient with membranous nephropathy during treatment with the immunosuppressant mizoribine

We report on an 80-year-old man diagnosed with Fanconi syndrome induced by mizoribine after 4 weeks of administration to treat membranous nephropathy. Mizoribine is an oral immunosuppressant that inhibits inosine monophosphate dehydrogenase and is widely used in Japan for the treatment of autoimmune diseases and nephrotic syndrome, as well as after renal transplantation. Acquired Fanconi syndrome is often caused by drugs (antibacterial, antiviral, anticancer, and anticonvulsant drugs) and is sometimes caused by autoimmune diseases, monoclonal light chain-associated diseases, or heavy metal poisoning. In our patient, hypokalemia, hypophosphatemia, glucosuria, hypouricemia, and severe proteinuria resolved gradually after discontinuation of mizoribine administration, despite oral administration of prednisolone followed by a single intravenous injection of rituximab. The patient was ultimately diagnosed with Fanconi syndrome induced by mizoribine based on his clinical course and his typical laboratory data with the absence of proximal tubular acidosis. To our knowledge, this is the first report of Fanconi syndrome possibly induced by mizoribine. Although the precise mechanism by which mizoribine induces proximal tubular dysfunction is unknown, we suggest that nephrologists should be aware of the onset of Fanconi syndrome, a rare complication during mizoribine treatment.

Therapeutic trials in difficult to treat steroid sensitive nephrotic syndrome: challenges and future directions

Steroid sensitive nephrotic syndrome is a common condition in pediatric nephrology, and most children have excellent outcomes. Yet, 50% of children will require steroid-sparing agents due to frequently relapsing disease and may suffer consequences from steroid dependence or use of steroid-sparing agents. Several steroid-sparing therapeutic agents are available with few high quality randomized controlled trials to compare efficacy leading to reliance on observational data for clinical guidance. Reported trials focus on short-term outcomes such as time to first relapse, relapse rates up to 1-2 years of follow-up, and few have studied long-term remission. Trial designs often do not consider inter-individual variability, and differing response to treatments may occur due to heterogeneity in pathogenic mechanisms, and genetic and environmental influences. Strategies are proposed to improve the quantity and quality of trials in steroid sensitive nephrotic syndrome with integration of biomarkers, novel trial designs, and standardized outcomes, especially for long-term remission. Collaborative efforts among international trial networks will help move us toward a shared goal of finding a cure for children with nephrotic syndrome.

Mizoribine halts kidney fibrosis in childhood IgA nephropathy: association with modulation of M2-type macrophages

BACKGROUND

The immunosuppressant mizoribine (Miz) can reduce progression of childhood IgA nephropathy (IgAN). This study examined whether Miz affects CD163⁺ M2-type macrophages which are associated with kidney fibrosis in childhood IgAN.

METHODS

A retrospective cohort of 90 children with IgAN were divided into groups treated with prednisolone (PSL) alone (P group; n = 42) or PSL plus Miz (PM group; n = 48) for a 2-year period. Normal human monocyte-derived macrophages were stimulated with dexamethasone (Dex), or Dex plus Miz, and analyzed by DNA microarray.

RESULTS

Clinical and histological findings at first biopsy were equivalent between patients entering the P and PM groups. Both treatments improved proteinuria and haematuria, and maintained normal kidney function over the 2-year course. The P group exhibited increased mesangial matrix expansion, increased glomerular segmental or global sclerosis, and increased interstitial fibrosis at 2-year biopsy; however, the PM group showed no progression of kidney fibrosis. These protective effects were associated with reduced numbers of glomerular and interstitial CD163⁺ macrophages in the PM versus P group. In cultured human macrophages, Dex induced upregulation of cytokines and growth factors, which was prevented by Miz. Miz also inhibited Dex-induced expression of CD300E, an activating receptor which can prevent monocyte apoptosis. CD300e expression by CD163⁺ macrophages was evident in the P group, which was reduced by Miz treatment.

CONCLUSION

Miz halted the progression of kidney fibrosis in PSL-treated pediatric IgAN. This was associated with reduced CD163⁺ and CD163⁺CD300e⁺ macrophage populations, plus in vitro findings that Miz can suppress steroid-induced macrophage expression of pro-fibrotic molecules. A higher resolution version of the Graphical abstract is available as Supplementary information.

Rhein Inhibits NF-κB Signaling Pathway to Alleviate Inflammatory Response and Oxidative Stress of Rats with Chronic Glomerulonephritis

Objective

To explore the effect and mechanism of rhein on chronic glomerulonephritis (CGN).

Method

Twenty-four eight-week-old male SD rats were randomly divided into following 4 groups (6 rats in each group): control group, CGN group, rhein group, and benazepril (Ben) group. And 5 mg/mL of cationization-bovine serum albumin (C-BSA) was mixed with an equal volume of Freund's incomplete adjuvant for the preparation of 2.5 mg/mL of C-BSA solution. The rat model of CGN was established by injection of C-BSA for six weeks. Calculation of the renal index in rats was conducted. Biochemical detection was performed to measure the level of 24 h urinary protein, blood urea nitrogen (BUN), serum creatinine (SCr), and serum albumin (ALB) of the rats, as well as the level of malondiadehyde (MDA), superoxide (SOD), and glutathione peroxidase (GSH-Px) in the kidney tissue. Hematoxylin and eosin (H&E) staining was utilized to measure histological changes in the kidney of the rats. The level of TNF-α, IL-1β, IL-6, and ICAM-1 in rat kidney tissues was determined by enzyme-linked immunosorbent assay (ELISA). Western blot was applied to check the expression of NF-κB in the nucleus and cytoplasm as well as the expression of IκBα and p-IκBα in rat kidney tissues.

Results

Rhein could decline urinary protein, restore blood biochemical parameters, and protect renal tissue in rats with CGN. Besides, rhein could inhibit the activity of the NF-κB signaling pathway in rats with CGN and could alleviate the inflammatory response and oxidative stress level at the same time.

Conclusion

Rhein alleviates inflammatory responses and oxidative stress in rats with CGN. It also provides a theoretical basis and data support for the therapeutic drugs for CGN.

Acute and severe ribavirin-associated hyperuricemia and acute kidney injury: An underrecognized adverse effect

Disclaimer

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

Purpose

To report a case of ribavirin-associated severe hyperuricemia in an immunocompromised patient treated for respiratory syncytial virus (RSV) infection.

Summary

A 21-year-old male with a past medical history of B-cell acute lymphoblastic leukemia was in full remission after allogenic bone marrow transplantation complicated with chronic graft-versus-host disease. He was hospitalized due to fever, malaise, and respiratory syndromes. A diagnosis of RSV upper respiratory tract infection complicated by secondary pneumonia was made, and oral ribavirin (600 mg in 3 divided doses daily) and intravenous levofloxacin (750 mg once daily) were initiated. On day 2 of the hospital admission, the patient’s uric acid levels had increased from a baseline of 4 to 6 mg/dL to values of 19.3 and 22.2 mg/dL after the fourth and fifth doses of ribavirin, respectively, and his serum creatinine steadily had increased from a baseline of 0.7 to 0.8 mg/dL to a value of 1.6 mg/dL. Ribavirin was discontinued after the sixth dose, and a single dose of intravenous rasburicase (7.5 mg) was administered. On day 3, the patient’s serum uric and creatinine concentrations had decreased to 4.7 mg/dL and 1.1 mg/dL, respectively. He continued to recover on antibiotics and was discharged with normal uric acid and serum creatinine levels.

Conclusion

We report a case of severe hyperuricemia and acute kidney injury that developed early after initiation of ribavirin for RSV infection and suspected bacterial pneumonia in an immunocompromised patient without hepatitis C, requiring ribavirin discontinuation and rasburicase administration. To our knowledge, this is the first reported case of severe hyperuricemia in a patient treated with ribavirin for RSV infection rather than chronic hepatitis C. Clinicians should be aware of the possibility of acute and severe hyperuricemia following ribavirin administration.

CD80 Insights as Therapeutic Target in the Current and Future Treatment Options of Frequent-Relapse Minimal Change Disease

Minimal change disease (MCD) is the most common cause of idiopathic nephrotic syndrome in children, and it is well known for its multifactorial causes which are the manifestation of the disease. Proteinuria is an early consequence of podocyte injury and a typical sign of kidney disease. Steroid-sensitive patients react well with glucocorticoids, but there is a high chance of multiple relapses. CD80, also known as B7-1, is generally expressed on antigen-presenting cells (APCs) in steroid-sensitive MCD patients. Various glomerular disease models associated with proteinuria demonstrated that the detection of CD80 with the increase of urinary CD80 was strongly associated closely with frequent-relapse MCD patients. The role of CD80 in MCD became controversial because one contradicts finding. This review covers the treatment alternatives for MCD with the insight of CD80 as a potential therapeutic target. The promising effectiveness of CD20 (rituximab) antibody and CD80 inhibitor (abatacept) encourages further investigation of CD80 as a therapeutic target in frequent-relapse MCD patients. Therapeutic-based antibody towards CD80 (galiximab) had never been investigated in MCD or any kidney-related disease; hence, the role of CD80 is still undetermined. A new therapeutic approach towards MCD is essential to provide broader effective treatment options besides the general immunosuppressive agents with gruesome adverse effects.

Non-corticosteroid immunosuppressive medications for steroid-sensitive nephrotic syndrome in children

BACKGROUND

About 80% of children with steroid-sensitive nephrotic syndrome (SSNS) have relapses. Of these children, half relapse frequently, and are at risk of adverse effects from corticosteroids. While non-corticosteroid immunosuppressive medications prolong periods of remission, they have significant potential adverse effects. Currently, there is no consensus about the most appropriate second-line agent in children who are steroid sensitive, but who continue to relapse. In addition, these medications could be used with corticosteroids in the initial episode of SSNS to prolong the period of remission. This is the fourth update of a review first published in 2001 and updated in 2005, 2008 and 2013.

OBJECTIVES

To evaluate the benefits and harms of non-corticosteroid immunosuppressive medications in SSNS in children with a relapsing course of SSNS and in children with their first episode of nephrotic syndrome.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 10 March 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs were included if they involved children with SSNS and compared non-corticosteroid immunosuppressive medications with placebo, corticosteroids (prednisone or prednisolone) or no treatment; compared different non-corticosteroid immunosuppressive medications or different doses, durations or routes of administration of the same non-corticosteroid immunosuppressive medication.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility, risk of bias of the included studies and extracted data. Statistical analyses were performed using a random-effects model and results expressed as risk ratio (RR) for dichotomous outcomes or mean difference (MD) for continuous outcomes with 95% confidence intervals (CI). The certainty of the evidence was assessed using GRADE.

MAIN RESULTS

We identified 43 studies (91 reports) and included data from 2428 children. Risk of bias assessment indicated that 21 and 24 studies were at low risk of bias for sequence generation and allocation concealment respectively. Nine studies were at low risk of performance bias and 10 were at low risk of detection bias. Thirty-seven and 27 studies were at low risk of incomplete and selective reporting respectively. Rituximab (in combination with calcineurin inhibitors (CNI) and prednisolone) versus CNI and prednisolone probably reduces the number of children who relapse at six months (5 studies, 269 children: RR 0.23, 95% CI 0.12 to 0.43) and 12 months (3 studies, 198 children: RR 0.63, 95% CI 0.42 to 0.93) (moderate certainty evidence). At six months, rituximab resulted in 126 children/1000 relapsing compared with 548 children/1000 treated with conservative treatments. Rituximab may result in infusion reactions (4 studies, 252 children: RR 5.83, 95% CI 1.34 to 25.29). Mycophenolate mofetil (MMF) and levamisole may have similar effects on the number of children who relapse at 12 months (1 study, 149 children: RR 0.90, 95% CI 0.70 to 1.16). MMF may have a similar effect on the number of children relapsing compared to cyclosporin (2 studies, 82 children: RR 1.90, 95% CI 0.66 to 5.46) (low certainty evidence). MMF compared to cyclosporin is probably less likely to result in hypertrichosis (3 studies, 140 children: RR 0.23, 95% CI 0.10 to 0.50) and gum hypertrophy (3 studies, 144 children: RR 0.09, 95% CI 0.07 to 0.42) (low certainty evidence). Levamisole compared with steroids or placebo may reduce the number of children with relapse during treatment (8 studies, 474 children: RR 0.52, 95% CI 0.33 to 0.82) (low certainty evidence). Levamisole compared to cyclophosphamide may make little or no difference to the risk for relapse after 6 to 9 months (2 studies, 97 children: RR 1.17, 95% CI 0.76 to 1.81) (low certainty evidence). Cyclosporin compared with prednisolone may reduce the number of children who relapse (1 study, 104 children: RR 0.33, 95% CI 0.13 to 0.83) (low certainty evidence). Alkylating agents compared with cyclosporin may make little or no difference to the risk of relapse during cyclosporin treatment (2 studies, 95 children: RR 0.91, 95% CI 0.55 to 1.48) (low certainty evidence) but may reduce the risk of relapse at 12 to 24 months (2 studies, 95 children: RR 0.51, 95% CI 0.35 to 0.74), suggesting that the benefit of the alkylating agents may be sustained beyond the on-treatment period (low certainty evidence). Alkylating agents (cyclophosphamide and chlorambucil) compared with prednisone probably reduce the number of children, who experience relapse at six to 12 months (6 studies, 202 children: RR 0.44, 95% CI 0.32 to 0.60) and at 12 to 24 months (4 studies, 59 children: RR 0.20, 95% CI 0.09 to 0.46) (moderate certainty evidence). IV cyclophosphamide may reduce the number of children with relapse compared with oral cyclophosphamide at 6 months (2 studies, 83 children: RR 0.54, 95% CI 0.34 to 0.88), but not at 12 to 24 months (2 studies, 83 children: RR 0.99, 95% CI 0.76 to 1.29) and may result in fewer infections (2 studies, 83 children: RR 0.14, 95% CI 0.03 to 0.72) (low certainty evidence). Cyclophosphamide compared to chlorambucil may make little or no difference in the risk of relapse after 12 months (1 study, 50 children: RR 1.31, 95% CI 0.80 to 2.13) (low certainty evidence).

AUTHORS' CONCLUSIONS

New studies incorporated in this review indicate that rituximab is a valuable additional agent for managing children with steroid-dependent nephrotic syndrome. However, the treatment effect is temporary, and many children will require additional courses of rituximab. The long-term adverse effects of this treatment are not known. Comparative studies of CNIs, MMF, levamisole and alkylating agents have demonstrated little or no differences in efficacy but, because of insufficient power; clinically important differences in treatment effects have not been completely excluded.

Assessment of factors associated with mizoribine responsiveness in children with steroid-dependent nephrotic syndrome

BACKGROUND

Several immunosuppressants have been used to treat children with steroid-dependent nephrotic syndrome (SDNS). Mizoribine (MZR) is an immunosuppressant used to maintain remission in children with SDNS, although its effectiveness for treating SDNS remains controversial. Therefore, in this study, we assessed the clinical factors associated with children having SDNS who were successfully treated with MZR.

METHODS

A total of 47 children with SDNS who underwent MZR treatment were retrospectively evaluated. Clinical features including pharmacokinetics after MZR administration were compared between MZR responders and non-responders.

RESULTS

The comparison of the two groups revealed no significant differences in age, body weight (BW), daily dose of MZR per BW, serum concentration 2 h after administration (C₂), peak serum concentration (C_max), and area under the concentration curve 0-4 h after administration (AUC_0-4). C₂/(single dose/BW), C_max/(single dose/BW), and AUC_0-4/(single dose/BW) were significantly higher in the MZR responders than in the non-responders (all p < 0.01). Receiver operating characteristic analysis revealed that the cutoff values of C₂ (single dose/kg), C_max/(single dose/BW), and AUC_0-4/(single dose/BW) were 0.55, 0.58, and 1.37, respectively.

CONCLUSIONS

MZR is a useful immunosuppressant for treating frequent-relapse NS in children who are susceptible to the drug. The efficacy of MZR may be associated with not only serum concentrations defined by the dosage or absorption efficiency through MZR transporters, but also the susceptibility defined by the expression level and performance of MZR transporters on the target cells.

Usefulness of mizoribine administration in children with frequently relapsing nephrotic syndrome, and the relationship between pharmacokinetic parameters and efficacy: a multicenter prospective cohort study in China

BACKGROUND

Mizoribine (MZR) is an immunosuppressant used to treat adult nephropathy. There is little experience with the drug in treating Chinese children with frequently relapsing nephrotic syndrome (FRNS). We investigated the efficacy and safety for treating MZR with FRNS. Furthermore, the relationship between efficacy and serum concentration was investigated.

METHODS

A prospective multicenter observational 12-month study was performed for evaluating the usefulness of MZR with FRNS. Serum MZR concentration was measured, and the relationships between pharmacokinetic parameters (C_max, AUC), number of relapses, and urinary protein were evaluated.

RESULTS

Eighty-two pediatric patients from four hospitals were treated with MZR and prednisone. MZR treatment significantly reduced the number of relapses and steroid doses. A correlation between pharmacokinetic parameters and relapses was observed, which fits well with the sigmoidal E_max model. Even in the relationship between pharmacokinetic parameters and urinary proteins, it was recognized that there was a threshold in the pharmacokinetic parameters for the therapeutic effect similar to the results obtained with the sigmoidal E_max model. Eleven patients (13.4%) experienced mild adverse events.

CONCLUSIONS

MZR therapy was effective in reducing the number of relapses and steroid doses. No severe adverse reactions were observed. Therapeutically effective serum concentrations were estimated to be C_max ≥ about 2 μg/mL or AUC ≥ about 10 μg h/mL. MZR and steroid treatment were effective and safe for pediatric FRNS.

Study protocol: high-dose mizoribine with prednisolone therapy in short-term relapsing steroid-sensitive nephrotic syndrome to prevent frequent relapse (JSKDC05 trial)

Background

Eighty percent of children with steroid-sensitive nephrotic syndrome (SSNS) relapse within 2 years and 40–50% patients show frequently-relapsing nephrotic syndrome (FRNS). Patients showing a relapse within 6 months after initial remission are at high risk of FRNS. Since frequent prednisolone treatment for FRNS induces severe prednisolone side effects, development of a treatment to prevent patients from shifting to FRNS is desirable. Mizoribine is an immunosuppressive drug with fewer side effects than prednisolone. Recent studies reported the efficacy of high-dose mizoribine in children with FRNS.

Methods/design

We conduct a multicenter, open, randomized controlled trial to investigate the efficacy and safety of standard prednisolone plus high-dose mizoribine therapy in children with SSNS showing a relapse within 6 months after an initial remission. Patients are allocated to either standard prednisolone alone treatment group, or standard prednisolone plus high-dose mizoribine group. For the former group, mizoribine is administered at a dose of 10 mg/kg/day once daily and continued for 2 years. The primary endpoint is the duration to frequent relapse.

Discussion

The results provide important data on use of high-dose mizoribine to prevent SSNS patients from shifting to FRNS. Since blood concentrations of mizoribine have not been investigated in detail until now, there is a possibility that mizoribine is underestimated in favor of other immunosuppressive drugs. In future, high-dose mizoribine therapy may lead to prevention of relapse in children at high risk of FRNS, and to decreased total dose of prednisolone.

Trial registration

UMIN000005103, (Prospectively registered 1st March 2011).

Idiopathic nephrotic syndrome in children

The incidence of idiopathic nephrotic syndrome (NS) is 1·15-16·9 per 100 000 children, varying by ethnicity and region. The cause remains unknown but the pathogenesis of idiopathic NS is thought to involve immune dysregulation, systemic circulating factors, or inherited structural abnormalities of the podocyte. Genetic risk is more commonly described among children with steroid-resistant disease. The mainstay of therapy is prednisone for the vast majority of patients who are steroid responsive; however, the disease can run a frequently relapsing course, necessitating the need for alternative immunosuppressive agents. Infection and venous thromboembolism are the main complications of NS with also increased risk of acute kidney injury. Prognosis in terms of long-term kidney outcome overall is excellent for steroid-responsive disease, and steroid resistance is an important determinant of future risk of chronic or end-stage kidney disease.

Favorable response to immunosuppressive combination therapy with mizoribine and azathioprine in children with primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC), with no curative intervention, can progress to end-stage liver disease. Mizoribine, a purine antimetabolite, has never been used for the management of PSC. To evaluate the role of mizoribine with azathioprine we undertook a preliminary clinical study in children with PSC. Children with PSC and autoimmune features were simultaneously treated with mizoribine and azathioprine. Ursodeoxycholic acid or mesalazine were not regulated. The primary end-points of our study included improvement of aspartate aminotransferase, alanine aminotransferase, and γ-glutamyltransferase. Liver histology, immunostaining studies of the liver, and magnetic resonance cholangiopancreatography (MRCP) were also assessed. We have treated four PSC children: two treatment-naïve patients (cases 1 and 2), and two with established liver cirrhosis (cases 3 and 4). Both case 1 and 2 showed a normalization of liver enzymes and case 2 showed an improvement in MRCP findings. Cases 3 and 4 also showed an improvement in varices, MRCP findings, and liver histology. The combination therapy may be effective for some children with PSC and autoimmune features. By ameliorating both parenchymal inflammation and cholangiopathy of PSC, the therapy might improve the prognosis for patients. It awaits further prospective studies to confirm the efficacy of this therapy in patients with PSC.

Mizoribine is as Effective as Methotrexate for the Treatment of Polymyalgia Rheumatica: A Retrospective Case Series Analysis

Objectives

This study aims to evaluate the efficacy and safety of mizoribine (MZR) as a steroid-sparing agent compared to methotrexate (MTX) in the treatment of polymyalgia rheumatica in elderly patients.

Patients and methods

Twenty-four patients (9 males, 15 females; mean age 71.7 years; range 50 to 86 years) diagnosed with polymyalgia rheumatica between April 1998 and August 2014, who received prednisone in combination with either MTX or MZR, were included. We collected the data on the cumulative prednisone dose that patients received within 48 weeks after MTX or MZR and its side effect profile.

Results

There were 10 patients in the MTX group and 14 in the MZR group. The cumulative prednisone dose over 0-48 weeks was 2272±396 mg in the MTX group and 1907±241 mg in the MZR group, which was not significantly different (p=0.41). In terms of side effects, in the MTX group, three patients experienced a transient elevation in liver enzymes, and one patient developed gastrointestinal symptoms that led to MTX withdrawal. In the MZR group, one patient was hospitalized due to pneumonia that led to MZR withdrawal.

Conclusion

Mizoribine was non-inferior to MTX in terms of steroid-sparing effects on polymyalgia rheumatica. Also, MZR tended to have fewer side effects than MTX.

Drug-induced hyperuricaemia and gout

Hyperuricaemia is a common clinical condition that can be defined as a serum uric acid level >6.8 mg/dl (404 µmol/l). Gout, a recognized complication of hyperuricaemia, is the most common inflammatory arthritis in adults. Drug-induced hyperuricaemia and gout present an emergent and increasingly prevalent problem in clinical practice. Diuretics are one of the most important causes of secondary hyperuricaemia. Drugs raise serum uric acid level by an increase of uric acid reabsorption and/or decrease in uric acid secretion. Several drugs may also increase uric acid production. In this review, drugs leading to hyperuricaemia are summarized with regard to their mechanism of action and clinical significance. Increased awareness of drugs that can induce hyperuricaemia and gout, and monitoring and prevention are key elements for reducing the morbidity related to drug-induced hyperuricaemia and gout.

Mizoribine Synchronized Methotrexate Therapy should be Considered when Treating Rheumatoid Arthritis Patients with an Inadequate Response to Various Combination Therapies

Objective The objective of this study was to confirm the efficacy of low-dose mizoribine (MZR), an inhibitor of inosine monophosphate dehydrogenase, as part of synchronized methotrexate (MTX) therapy for rheumatoid arthritis (RA) patients with an inadequate response to various combination therapies of MTX, other synthetic disease-modifying anti-rheumatic drugs (DMARDs) and biological DMARDs. Methods Low-dose MZR was administered to 56 uncontrolled RA patients being treated with MTX and various biological DMARDs. The observation period was 12 months, and the disease activity was evaluated based on the Disease Activity Score in 28 joints (DAS28)-ESR, Simplified Disease Activity Index (SDAI) and serum MMP-3 level. Results All of the disease activity indices were significantly improved within three months, and the serum MMP-3 levels were also significantly decreased around four months after starting low-dose MZR therapy. No patients experienced any adverse effects. Conclusion The present preliminary findings suggest that low-dose MZR therapy with MTX should be considered for the treatment of RA patients with an inadequate response to various combination therapies including MTX, other synthetic DMARDs and biological DMARDs or in whom increasing the dose of MTX is difficult for reasons such as adverse effects and complications.

Mizoribine therapy combined with steroids and mizoribine blood concentration monitoring for idiopathic membranous nephropathy with steroid-resistant nephrotic syndrome

Background

We designed a prospective and randomized trial of mizoribine (MZR) therapy combined with prednisolone (PSL) for idiopathic membranous nephropathy (IMN) with steroid-resistant nephrotic syndrome (SRNS).

Methods

Patients with IMN were divided into 2 groups, and MZR combined with PSL was administered for 2 years. PSL was initially prescribed at 40 mg/day and tapered. MZR was given once-a-day at 150 mg and 3-times-a-day at 50 mg each to groups 1 and 2. Serum MZR concentrations from 0 to 4 h after administration were examined within one month of treatment. The concentration curve and peak serum level (C_max) of MZR were estimated by the population pharmacokinetic (PPK) parameters of MZR.

Results

At 2 years, 10 of 19 patients (52.6 %) in group 1 and 7 of 18 patients (38.9 %) in group 2 achieved complete remission (CR). The time-to-remission curve using the Kaplan–Meier technique revealed an increase in the cumulative CR rate in group 1, but no significant difference between the groups. Meanwhile, there was a significant difference in C_max between groups 1 and 2 (mean ± SD: 1.20 ± 0.52 vs. 0.76 ± 0.39 μg/mL, p = 0.04), and C_max levels in CR cases were significantly higher than those in non-CR cases. Receiver operating characteristic analysis showed that C_max more than 1.1 µg/mL was necessary for CR in once-a-day administration.

Conclusion

Administration of MZR once a day is useful when combined with PSL for treatment of IMN with SRNS. In addition, it is important to assay the serum concentration of MZR and to determine C_max, and more than 1.1 µg/mL of C_max is necessary for CR.

Steroid-sensitive nephrotic syndrome: an evidence-based update of immunosuppressive treatment in children

Nephrotic syndrome is one of the most common paediatric glomerular diseases, with an incidence of around two per 100,000 children per year. Corticosteroids are the mainstay of treatment, with 85%-90% of children going into remission with an 8-week course of treatment. Unfortunately, nephrotic syndrome follows a relapsing and remitting course in the majority, with 90% relapsing at least once. About half will progress to frequently relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS). Different initial steroid regimens have been evaluated since the first trials in Europe and America in the 1960s. Most trials have been designed to evaluate the optimal duration of the initial therapy, rather than different cumulative doses of corticosteroid, or the management of relapses. Until recently, these data suggested that an initial treatment duration of up to 6 months reduced the number of children developing a relapse, without evidence of increased steroid toxicity. Recently, three large, well-designed randomised control trials were published, which demonstrated no significant reduction in risk of relapse or of developing FRNS by extended treatment compared with 2 or 3 months. While there are few trial data to guide the treatment of individual relapses in steroid-sensitive nephrotic syndrome (SSNS), there is some evidence that a short course of corticosteroid therapy during upper respiratory tract infection may prevent relapse. In patients with FRNS or SDNS who continue to relapse despite low-dose alternate-day steroids a number of non-corticosteroid, steroid-sparing immunosuppressive agents (cyclophosphamide, ciclosporin, tacrolimus, mycophenolate mofetil, levamisole, rituximab) have been shown to reduce the risk of relapse and of FRNS. However, there are limited head-to-head data to inform which agent should be preferred. In this article, we review recent data from randomised trials to update paediatricians on the current evidence supporting interventions in SSNS.

Comparison of steroid-pulse therapy and combined with mizoribine in IgA nephropathy: a randomized controlled trial

BACKGROUND

The significance of immunosuppressants as an adjunct treatment with corticosteroids for IgA nephropathy (IgAN) has not been well demonstrated. This study was performed to compare two treatment regimens, steroid-pulse therapy or combined with mizoribine (MZR) in progressive IgAN.

METHODS

Study design was a prospective randomized controlled trial of 40 patients with moderate to severe glomerular injuries who were randomly administered either pulse methylprednisolone followed by a 25-month course of oral prednisolone (P group, n = 20) or in combination with MZR (150 mg/day for 24 months, M + P group, n = 20). The primary endpoint was a reduction of proteinuria by ≥50 % of the baseline value. Secondary endpoints were increased serum creatinine (Cr) by ≥50 %, or a decrease in estimated glomerular filtration rate by ≤50 %.

RESULTS

Twenty-five months after the initiation of treatment, urinary protein excretion significantly declined from the median of 0.98 to 0.17 g/gCr in the P group (P < 0.05) and from 1.01 to 0.38 g/gCr in the M + P group (P < 0.05). There was no statistical difference in the serial changes of proteinuria between two groups (P = 0.81). All patients reached the primary endpoint, and the cumulative incidence of the reduction of proteinuria was not significantly different (P = 0.76). No patient reached the secondary endpoint during the 25 months of treatment.

CONCLUSIONS

Both therapeutic regimens significantly reduced the levels of proteinuria. We could not find the additional effect of MZR in combination with steroid-pulses in this small-scale controlled trial. Steroid-pulse therapy with a 25-month course of oral steroids seems to be effective for progressive IgAN.

Population pharmacokinetics of mizoribine in pediatric patients with kidney disease

BACKGROUND

The present study aimed to obtain information enabling optimisation of the clinical effect of mizoribine (MZR) in pediatric patients with kidney disease.

METHODS

A total of 105 pediatric patients with kidney disease treated at our institutions were enrolled. Kidney transplant patients were excluded. Population pharmacokinetic analysis of MZR was performed based on serum concentration data. Area under the curve from time zero to infinity (AUC_∞) and maximal concentration (C _max) were calculated by Bayesian analysis.

RESULTS

In children, the appearance of MZR in the blood tended to be slower and the subsequent rise in blood concentration tended to be more sluggish, compared to healthy adults. Apparent volume of distribution and oral clearance were also higher in children compared to adults. A significant positive correlation was observed between patient age and AUC_∞. There were significant differences of AUC_∞ and C _max by age group. No relationship was observed between the administration method of MZR and serum concentration.

CONCLUSION

The pharmacokinetics of MZR was different in children compared to adults. To obtain the expected clinical efficacy, the regular MZR dosage schedule (2-3 mg/kg/day) might be insufficient for pediatric patients. In particular, younger patients might require a higher dosage of MZR per unit body weight.

Mizoribine in the treatment of pediatric-onset glomerular disease

BACKGROUND

Mizoribine (MZR) is a selective inhibitor of inosine monophosphate dehydrogenase, a key enzyme in the pathway responsible for de novo synthesis of guanine nucleotides. As an immunosuppressant, MZR has been used successfully without any serious adverse effects in the treatment of renal diseases in children as well as adults. Besides its immunosuppressive effect, MZR has been reported to ameliorate tubulointerstitial fibrosis in rats via suppression of macrophage infiltration.

DATA SOURCES

In this review, we summarize reported possible benefits of MZR in the treatment of pediatriconset glomerular disease.

RESULTS

We recently observed that MZR itself selectively attenuates the expression of monocyte chemoattractant protein-1 at both the mRNA and protein levels in human mesangial cells. Since MZR binds specifically to 14-3-3 proteins and heat shock protein 60, both of which are reportedly expressed in inflamed glomeruli, MZR may bind directly to inflamed glomerular cells, thereby possibly preventing progressive damage from glomerulonephritis through a suppressive effect on activated macrophages and intrinsic renal cells. Moreover, it has recently been reported that MZR directly prevents podocyte injury through correction of the intracellular energy balance and nephrin biogenesis in cultured podocyte and rat models, suggesting a direct anti-proteinuric effect of MZR.

CONCLUSIONS

These beneficial mechanisms of action of MZR as well as its immunosuppressive effect would warrant its use in the treatment of pediatric-onset glomerular disease. Although further studies remain to be done, we believe that MZR may be an attractive treatment of choice for children with glomerular diseases from a histologic as well as clinical standpoint.

Corticosteroid therapy for nephrotic syndrome in children

BACKGROUND

In nephrotic syndrome protein leaks from the blood to the urine through the glomeruli resulting in hypoproteinaemia and generalised oedema. While most children with nephrotic syndrome respond to corticosteroids, 80% experience a relapsing course. Corticosteroids have reduced the mortality rate to around 3%. However corticosteroids have well recognised potentially serious adverse effects such as obesity, poor growth, hypertension, diabetes mellitus, osteoporosis and behavioural disturbances. This is an update of a review first published in 2000 and updated in 2003, 2005 and 2007.

OBJECTIVES

The aim of this review was to assess the benefits and harms of different corticosteroid regimens in children with steroid-sensitive nephrotic syndrome (SSNS). The benefits and harms of therapy were studied in two groups of children 1) children in their initial episode of SSNS, and 2) children who experience a relapsing course of SSNS.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 26 February 2015 through contact with the Trials Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) performed in children (three months to 18 years) in their initial or subsequent episode of SSNS, comparing different durations, total doses or other dose strategies using any corticosteroid agent.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed risk of bias and extracted data. Results were expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

Ten new studies were identified so a total of 34 studies (3033 total participants) were included in the 2015 review update. The risk of bias attributes were frequently poorly performed. Low risk of bias was reported in 18 studies for sequence generation, 16 studies for allocation concealment, seven for performance and detection bias, 15 for incomplete reporting and 16 for selective reporting. Three months or more of prednisone significantly reduced the risk of frequently relapsing nephrotic syndrome (FRNS) (6 studies, 582 children: RR 0.68, 95% CI 0.47 to 1.00) and of relapse by 12 to 24 months (8 studies, 741 children: RR 0.80, 95% CI 0.64 to 1.00) compared with two months. Five or six months of prednisone significantly reduced the risk of relapse (7 studies, 763 children: RR 0.62, 95% CI 0.45 to 0.85) but not FRNS (5 studies, 591 children: RR 0.78, 95% CI 0.50 to 1.22) compared with three months. However there was significant heterogeneity in the analyses. Subgroup analysis stratified by risk of bias for allocation concealment showed that the risk for FRNS did not differ significantly between two or three months of prednisone and three to six months among studies at low risk of bias but was significantly reduced in extended duration studies compared with two or three months in studies at high risk or unclear risk of bias. There were no significant differences in the risk of adverse effects between extended duration and two or three months of prednisone. Four studies found that in children with FRNS, daily prednisone during viral infections compared with alternate-day prednisone or no treatment significantly reduced the rate of relapse.

AUTHORS' CONCLUSIONS

In this 2015 update the addition of three well-designed studies has changed the conclusion of this review. Studies of long versus shorter duration of corticosteroids have heterogeneous treatment effects, with the older high risk of bias studies tending to over-estimate the effect of longer course therapy, compared with more recently published low risk of bias studies. Among studies at low risk of bias, there was no significant difference in the risk for FRNS between prednisone given for two or three months and longer durations or total dose of therapy indicating that there is no benefit of increasing the duration of prednisone beyond two or three months in the initial episode of SSNS.The risk of relapse in children with FRNS is reduced by the administration of daily prednisone at onset of an upper respiratory tract or viral infection. Three additional studies have increased the evidence supporting this conclusion. This management strategy may be considered for children with FRNS. A paucity of data on prednisone use in relapsing nephrotic syndrome remains. In particular there are no data from RCTs evaluating the efficacy and safety of prolonged courses of low dose alternate-day prednisone although this management strategy is recommended in current guidelines.

Immunosuppressive treatment for idiopathic membranous nephropathy in adults with nephrotic syndrome

BACKGROUND

Idiopathic membranous nephropathy (IMN) is the most common form of nephrotic syndrome in adults. The disease shows a benign or indolent course in the majority of patients, with a rate of spontaneous complete or partial remission of nephrotic syndrome as high as 30% or more. Despite this, 30% to 40% of patients progress toward end-stage kidney disease (ESKD) within five to 15 years. The efficacy and safety of immunosuppression for IMN with nephrotic syndrome are still controversial. This is an update of a Cochrane review first published in 2004.

OBJECTIVES

The aim of this review was to evaluate the safety and efficacy of immunosuppressive treatments for adult patients with IMN and nephrotic syndrome. Moreover it was attempted to identify the best therapeutic regimen, when to start immunosuppression and whether the above therapies should be given to all adult patients at high risk of progression to ESKD or only restricted to those with impaired kidney function.

SEARCH METHODS

We searched Cochrane Renal Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Chinese databases, reference lists of articles, and clinical trial registries to June 2014. We also contacted principal investigators of some of the studies for additional information.

SELECTION CRITERIA

Randomised controlled trials (RCTs) investigating the effects of immunosuppression in adults with IMN and nephrotic syndrome.

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, quality assessment, and data synthesis were performed using the Cochrane-recommended methods. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes.

MAIN RESULTS

Thirty nine studies with 1825 patients were included, 36 of these could be included in our meta-analyses. The data from two studies could not be extracted and one study was terminated due to poor accrual. Immunosuppression significantly reduced all-cause mortality or risk of ESKD ((15 studies, 791 patients): RR 0.58 (95% CI 0.36 to 0.95, P = 0.03) and risk of ESKD ((15 studies, 791 patients): RR 0.55, 95% CI 0.31 to 0.95, P = 0.03), increased complete or partial remission ((16 studies, 864 patients): RR 1.31, 95% CI 1.01 to 1.70, P = 0.04), and decreased proteinuria ((9 studies,(393 patients): MD -0.95 g/24 h, 95% CI -1.81 to -0.09, P = 0.03) at the end of follow-up (range 6 to 120 months). However this regimen was associated with more discontinuations or hospitalisations ((16 studies, 880 studies): RR 5.35, 95% CI 2.19 to 13.02), P = 0.0002). Combined corticosteroids and alkylating agents significantly reduced death or risk of ESKD ((8 studies, 448 patients): RR 0.44, 95% CI 0.26 to 0.75, P = 0.002) and ESKD ((8 studies, 448 patients): RR 0.45, 95% CI 0.25 to 0.81, P = 0.008), increased complete or partial remission ((7 studies, 422 patients): RR 1.46, 95% CI 1.13 to 1.89, P = 0.004) and complete remission ((7 studies, 422 patients): RR 2.32, 95% CI 1.61 to 3.32, P < 0.00001), and decreased proteinuria ((6 studies, 279 patients): MD -1.25 g/24 h, 95% CI -1.93 to -0.57, P = 0.0003) at the end of follow-up (range 9 to 120 months). In a population with an assumed risk of death or ESKD of 181/1000 patients, this regimen would be expected to reduce the number of patients experiencing death or ESKD to 80/1000 patients (range 47 to 136). In a population with an assumed complete or partial remission of 408/1000 patients, this regimen would be expected to increase the number of patients experiencing complete or partial remission to 596/1000 patients (range 462 to 772). However this combined regimen was associated with a significantly higher risk of discontinuation or hospitalisation due to adverse effects ((4 studies, 303 patients): RR 4.20, 95% CI 1.15 to 15.32, P = 0.03). Whether this combined therapy should be indicated in all adult patients at high risk of progression to ESKD or only restricted to those with deteriorating kidney function still remained unclear. Cyclophosphamide was safer than chlorambucil ((3 studies, 147 patients): RR 0.48, 95% CI 0.26 to 0.90, P = 0.02). There was no clear evidence to support the use of either corticosteroid or alkylating agent monotherapy. Cyclosporine and mycophenolate mofetil failed to show superiority over alkylating agents. Tacrolimus and adrenocorticotropic hormone significantly reduced proteinuria. The numbers of corresponding studies related to tacrolimus, mycophenolate mofetil, adrenocorticotropic hormone, azathioprine, mizoribine, and Tripterygium wilfordii are still too sparse to draw final conclusions.

AUTHORS' CONCLUSIONS

In this update, a combined alkylating agent and corticosteroid regimen had short- and long-term benefits on adult IMN with nephrotic syndrome. Among alkylating agents, cyclophosphamide was safer than chlorambucil. This regimen was significantly associated with more withdrawals or hospitalisations. It should be emphasised that the number of included studies with high-quality design was relatively small and most of included studies did not have adequate follow-up and enough power to assess the prespecified definite endpoints. Although a six-month course of alternating monthly cycles of corticosteroids and cyclophosphamide was recommended by the KDIGO Clinical Practice Guideline 2012 as the initial therapy for adult IMN with nephrotic syndrome, clinicians should inform their patients of the lack of high-quality evidence for these benefits as well as the well-recognised adverse effects of this therapy. Cyclosporine or tacrolimus was recommended by the KDIGO Clinical Practice Guideline 2012 as the alternative regimen for adult IMN with nephrotic syndrome; however, there was no evidence that calcineurin inhibitors could alter the combined outcome of death or ESKD.

Synergistic protective effects of mizoribine and angiotensin II receptor blockade on cyclosporine A nephropathy in rats

BACKGROUND

Chronic cyclosporine A (CsA) nephrotoxicity is manifested by renal dysfunction, progressive histopathological kidney lesions characterized by afferent arteriolopathy, and tubulointerstitial fibrosis. In addition to the direct toxic effect of CsA, many other etiological factors such as angiotensin II, transforming growth factor (TGF)-β, and macrophage infiltration are involved in this pathogenesis. This study investigated the hypothesis that concomitant administration of mizoribine (MZR) and angiotensin II receptor blockade (ARB) may prevent CsA nephrotoxicity in rats.

METHODS

Sprague-Dawley male rats were divided into the following seven groups: group 1, treated with CsA; group 2, treated with CsA + MZR; group 3, treated with CsA + valsartan (Val); group 4, treated with CsA + MZR + Val; group 5, treated with MZR; group 6, treated with Val; and group 7, controls (n = 5 each). Renal histopathology and the effect of CsA-induced nephrotoxicity on inflammatory mediators were evaluated.

RESULTS

Results of this study demonstrated that ARB administration significantly decreased arteriolopathy and that in comparison with monotherapy, concomitant administration of MZR and ARB further decreased arteriolopathy, fibrosis, macrophage infiltration, and TGF-β1 mRNA expression associated with CsA nephrotoxicity.

CONCLUSION

These findings indicate that MZR and ARB combination treatment provides synergistic protective effects against chronic CsA nephrotoxicity.

Mizoribine as a safe and effective combined maintenance therapy with prednisolone for anti-neutrophil cytoplasmic antibody-associated vasculitis in a hemodialysis patient

A 77-year-old man developed severe renal insufficiency due to proteinase 3 anti-neutrophil cytoplasmic antibody (PR3-ANCA)-associated vasculitis, and was started on hemodialysis (HD). Because his renal insufficiency appeared to be irreversible, he was maintained on oral prednisolone (PSL) at 5 mg/day. However, a disease flare-up with alveolar hemorrhage occurred. Serology revealed elevated levels of PR3-ANCA and C-reactive protein (CRP). The patient was given pulse therapy with a quarter dose of methylprednisolone (m-PSL) (250 mg, 3 days), followed by oral PSL at 15 mg/day. As a supplemental treatment, he was given 25 mg of mizoribine (MZR) immediately after each HD session. Subsequently, the levels of PR3-ANCA and CRP decreased, and the alveolar hemorrhage resolved. The dose of MZR to be given was determined by measuring the patient's serum concentrations of MZR at various time points after the HD session. The maintenance dose of MZR was finally set at 50 mg. At present, the oral PSL dosage has been tapered to 10 mg/day, and the patient has achieved a state of remission without any side effects.

Non-corticosteroid immunosuppressive medications for steroid-sensitive nephrotic syndrome in children

BACKGROUND

About 80% to 90% of children with steroid-sensitive nephrotic syndrome (SSNS) have relapses. Of these children, around half relapse frequently, and are at risk of adverse effects from corticosteroids. Non-corticosteroid immunosuppressive medications are used to prolong periods of remission in these children; however, these medications have significant potential adverse effects. Currently, there is no consensus about the most appropriate second line agent in children who are steroid sensitive, but who continue to relapse. This is the third update of a review first published in 2001 and updated in 2005 and 2008.

OBJECTIVES

To evaluate the benefits and harms of non-corticosteroid immunosuppressive medications in relapsing SSNS in children.

SEARCH METHODS

For this update we searched the Cochrane Renal Group's Specialised Register to June 2013.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs were included if they compared non-corticosteroid immunosuppressive medications with placebo, prednisone or no treatment, different non-corticosteroid immunosuppressive medications and different doses, durations or routes of administration of the same non-corticosteroid immunosuppressive medication.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the risk of bias of the included studies and extracted data. Statistical analyses were performed using a random-effects model and results expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We identified 32 studies (1443 children) of which one study is still ongoing. In the 31 studies with data, risk of bias assessment indicated that 11 (37%) and 16 (53%) studies were at low risk of bias for sequence generation and allocation concealment respectively. Six (29%) studies were at low risk of performance and detection bias. Twenty seven (87%) and 19 (60%) studies were at low risk of incomplete and selective reporting respectively. Alkylating agents (cyclophosphamide and chlorambucil) significantly reduced the risk of relapse at six to 12 months (RR 0.43, 95% CI 0.31 to 0.60) and 12 to 24 months (RR 0.20, 95% CI 0.09 to 0.46) compared with prednisone alone. There was no significant difference in relapse risk at two years between chlorambucil and cyclophosphamide (RR 1.31, 95% CI 0.80 to 2.13). There was no significant difference at one year between intravenous and oral cyclophosphamide (RR 0.99, 95% CI 0.76 to 1.29). Cyclosporin was as effective as cyclophosphamide (RR 1.07, 95% CI 0.48 to 2.35) and chlorambucil (RR 0.82, 95% CI 0.44 to 1.53) at the end of therapy while levamisole (RR 0.47, 95% CI 0.24 to 0.89) was more effective than steroids alone. However the effects of cyclosporin and levamisole were not sustained once treatment was stopped. In one small study cyclosporin significantly reduced the relapse rate compared with mycophenolate mofetil (MD 0.75, 95% CI 0.01 to 1.49). Limited data from a cross-over study suggested that cyclosporin was more effective than mycophenolate mofetil in maintaining remission. In steroid- and cyclosporin-dependent disease, rituximab significantly reduced the risk of relapse at three months compared with conventional therapy. Mizoribine and azathioprine were no more effective than placebo or prednisone alone in maintaining remission.

AUTHORS' CONCLUSIONS

Eight-week courses of cyclophosphamide or chlorambucil and prolonged courses of cyclosporin and levamisole reduce the risk of relapse in children with relapsing SSNS compared with corticosteroids alone. Limited data indicate that mycophenolate mofetil and rituximab are valuable additional medications for relapsing SSNS. However clinically important differences in efficacy are possible and further comparative studies are still needed.

Therapeutic effect of mizoribine on pemphigus vulgaris and pemphigus foliaceus

We evaluated the effectiveness of mizoribine, a newly developed immunosuppressive agent, as an adjuvant therapy in the treatment of both pemphigus vulgaris and pemphigus foliaceus. Eleven pemphigus patients (eight pemphigus vulgaris and three pemphigus foliaceus) received the combination therapy of prednisolone and mizoribine. Complete remission was observed in three of the eight patients with pemphigus vulgaris and in one of the three patients with pemphigus foliaceus. The four patients with complete remission had a rapid clinical response and achieved remission at a median of 11.8 months. Partial remission was achieved in two of the three patients with pemphigus foliaceus. The median time to achieve partial remission was 16.0 months. Six (55.6%) of the 11 patients with pemphigus had complete or partial remission and were able to taper their prednisolone. The cumulative probability of having a complete remission was 64.3% at 19 months of follow-up using Kaplan-Meier analysis. The effectiveness of the additional mizoribine therapy could be attributed to its corticosteroid-sparing properties as well as its immunosuppressive effects. The serum concentration titer of mizoribine was around 1.0 μg/mL 2 hours after administration. Patients who were not improved by the additional mizoribine might require a continuously higher dose of mizoribine to achieve effective therapy.

Treatment of steroid-sensitive nephrotic syndrome: new guidelines from KDIGO

The 2012 Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guideline on glomerulonephritis (GN) is intended to assist the practitioner caring for patients with GN. Two chapters of this guideline focus specifically on nephrotic syndrome in children. Guideline development followed a thorough evidence review, and management recommendations and suggestions were based on the best available evidence. Critical appraisal of the quality of evidence and strength of recommendations followed the Grades of Recommendation Assessment, Development and Evaluation (GRADE) approach. Chapters 3 and 4 of the guideline focus on the management of nephrotic syndrome in children aged 1-18 years. Guideline recommendations for children who have steroid-sensitive nephrotic syndrome (SNSS), defined by their response to corticosteroid therapy with complete remission, are addressed here. Recommendations for those with steroid-resistant nephrotic syndrome (SRNS) (i.e., do not achieve complete remission) are discussed in the companion article. Limitations of the evidence, including the paucity of large-scale randomized controlled trials, are discussed. This article provides a short description of the KDIGO process, the guideline recommendations for treatment of SSNS in children and a brief review of relevant treatment trials related to each recommendation.

The immunosuppressive agent mizoribine monophosphate is an inhibitor of the human RNA capping enzyme

Mizoribine monophosphate (MZP) is a specific inhibitor of the cellular inosine-5′-monophosphate dehydrogenase (IMPDH), the enzyme catalyzing the rate-limiting step of de novo guanine nucleotide biosynthesis. MZP is a highly potent antagonistic inhibitor of IMPDH that blocks the proliferation of T and B lymphocytes that use the de novo pathway of guanine nucleotide synthesis almost exclusively. In the present study, we investigated the ability of MZP to directly inhibit the human RNA capping enzyme (HCE), a protein harboring both RNA 5′-triphosphatase and RNA guanylyltransferase activities. HCE is involved in the synthesis of the cap structure found at the 5′ end of eukaryotic mRNAs, which is critical for the splicing of the cap-proximal intron, the transport of mRNAs from the nucleus to the cytoplasm, and for both the stability and translation of mRNAs. Our biochemical studies provide the first insight that MZP can inhibit the formation of the RNA cap structure catalyzed by HCE. In the presence of MZP, the RNA 5′-triphosphatase activity appears to be relatively unaffected while the RNA guanylyltransferase activity is inhibited, indicating that the RNA guanylyltransferase activity is the main target of MZP inhibition. Kinetic studies reveal that MZP is a non-competitive inhibitor that likely targets an allosteric site on HCE. Mizoribine also impairs mRNA capping in living cells, which could account for the global mechanism of action of this therapeutic agent. Together, our study clearly demonstrates that mizoribine monophosphate inhibits the human RNA guanylyltransferase in vitro and impair mRNA capping in cellulo.

Mizoribine requires individual dosing due to variation of bioavailability

BACKGROUND

Mizoribine (MZR) is an immunosuppressant used for the treatment of glomerular diseases, but there are few reports on the pharmacokinetics of MZR in children.

METHODS

First, we performed a pharmacokinetic study on nine childhood-onset glomerular disease patients. The MZR dosages ranged from 1.8 to 14.5 mg/kg/dose. Pharmacokinetic parameters were analyzed using 38 MZR concentration-time curves. Second, nine patients who were newly treated with MZR were enrolled to validate the findings obtained from prior investigation.

RESULTS

In the prior study, peak serum MZR concentration (C(max) ) was dose-dependent in each patient. Although proportionality between dosage and C(max) was observed in each patient, the regression coefficient was in a wide range from 0.075 to 1.04 and was specific to each patient. This variability was likely caused by individual variation of bioavailability. When the optimal time-point to monitor C(max) was investigated, the time-to-reach peak serum MZR concentration (T(max)) was similar among all the patients, which was from 2.5 to 3.5 h after administration of MZR. T(max) was most frequently observed at 3 h and the serum MZR concentration ratio relative to C(max) at 3 h was also highest (0.93 ± 0.07). In the following study, it was validated that monitoring C(3) is reproducible and reliable after adjusting the dosage of MZR to obtain target serum concentration.

CONCLUSION

Individual dosing is required to optimize C(max) in childhood-onset glomerular disease patients. The safe dosage of MZR for each patient could be predicted by evaluating the serum MZR concentration 3 h after administration.

Two-year follow-up of a prospective clinical trial of cyclosporine for frequently relapsing nephrotic syndrome in children

BACKGROUND AND OBJECTIVES

Although the safety and efficacy of cyclosporine in children with frequently relapsing nephrotic syndrome (FRNS) have been confirmed, no prospective follow-up data on relapse after cyclosporine have appeared. This study is a prospective follow-up trial after 2-year treatment with cyclosporine to investigate cyclosporine dependency after its discontinuation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Participants who had undergone 2-year protocol treatment with microemulsified cyclosporine for FRNS between January 2000 and December 2005 were followed for an additional 2 years. The primary end point was relapse-free survival after the complete discontinuation of cyclosporine, and the secondary end point was regression-free survival (time to regression to FRNS).

RESULTS

After exclusion of 7 patients who showed regression to FRNS during the 2-year treatment period, 49 children (median age, 6.5 years) were followed, and classified as children without (n=32; group A) and with (n=17; group B) relapse during the initial cyclosporine treatment. Overall, relapse-free survival probability at 24 months after cyclosporine discontinuation was 15.3% and regression to FRNS-free survival probability was 40.8%. By group, the probability of relapse-free survival was significantly higher in group A (17.9%) than in group B (8.3%) (P<0.001).

CONCLUSIONS

Children with FRNS who receive cyclosporine are at high risk of relapse after discontinuation, particularly those who experience relapse during cyclosporine treatment.

The Efficacy of Mizoribine (Inosine Monophosphate Dehydrogenase Inhibitor) for ANCA-Associated Vasculitis with Hepatitis B Virus Carrier

A 42-year-old female who was an asymptomatic carrier of hepatitis B virus (HBV) was diagnosed with antineutrophil cytoplasm antibody- (ANCA-) associated vasculitis and was induced to remission with 30 mg/day prednisolone nine years ago. Four years ago, she suffered recurrence of ANCA-associated vasculitis and with 30 mg/day prednisolone was induced to remission. This time, laboratory data showed 3-fold increase in myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) levels. Administration of 30 mg/day prednisolone was started. Three days later, she was admitted to our hospital suffering from fatigue. After admission, urinalysis showed glomerular hematuria. Despite administration of 30 mg/day prednisolone, MPO-ANCA titer had been of high level, ranging from 42 to 83 EU for 2.5 months. Furthermore, the adverse effects of steroid were seen. We decided the tapering of prednisolone (25 mg/day) and the start of mizoribine (4-carbamoyl-1-β-D-ribofuranosyl imidazolium-5-olate) administration. After mizoribine treatment, MPO-ANCA titer was decreased without any mizoribine-related adverse effects. Six months later, MPO-ANCA titer was decreased to normal levels and she was induced to clinical remission without reactivation of HBV. We describe the effectiveness of mizoribine for the ANCA-associated vasculitis complicated with HBV-carrier.