Combination therapy of prednisone and ACE inhibitor versus ACE-inhibitor therapy alone in patients with IgA nephropathy: a randomized controlled trial

Immunosuppressive treatment results in patients with primary IgA nephropathy in Turkiye; the data from TSN-GOLD working group

BACKGROUND

Immunoglobulin A (IgA) nephropathy (IgAN) treatment consists of maximal supportive care and, for high-risk individuals, immunosuppressive treatment (IST). There are conflicting results regarding IST. Therefore, we aimed to investigate IST results among IgAN patients in Turkiye.

METHOD

The data of 1656 IgAN patients in the Primary Glomerular Diseases Study of the Turkish Society of Nephrology Glomerular Diseases Study Group were analyzed. A total of 408 primary IgAN patients treated with IST (65.4% male, mean age 38.4 ± 12.5 years, follow-up 30 (3-218) months) were included and divided into two groups according to treatment protocols (isolated corticosteroid [CS] 70.6% and combined IST 29.4%). Treatment responses, associated factors were analyzed.

RESULTS

Remission (66.7% partial, 33.7% complete) was achieved in 74.7% of patients. Baseline systolic blood pressure, mean arterial pressure, and proteinuria levels were lower in responsives. Remission was achieved at significantly higher rates in the CS group (78% vs. 66.7%, p = 0.016). Partial remission was the prominent remission type. The remission rate was significantly higher among patients with segmental sclerosis compared to those without (60.4% vs. 49%, p = 0.047). In the multivariate analysis, MEST-C S1 (HR 1.43, 95% CI 1.08-1.89, p = 0.013), MEST-C T1 (HR 0.68, 95% CI 0.51-0.91, p = 0.008) and combined IST (HR 0.66, 95% CI 0.49-0.91, p = 0.009) were found to be significant regarding remission.

CONCLUSION

CS can significantly improve remission in high-risk Turkish IgAN patients, despite the reliance on non-quantitative endpoints for favorable renal outcomes. Key predictors of remission include baseline proteinuria and specific histological markers. It is crucial to carefully weigh the risks and benefits of immunosuppressive therapy for these patients.

New therapies for immunoglobulin A nephropathy: what's the standard of care in 2023?

PURPOSE OF REVIEW

As the most common primary glomerulonephritis, immunoglobulin A (IgA) nephropathy (IgAN) is an important cause of kidney failure and mortality. Until recently, therapeutic options were limited. Fortunately, there have been numerous recent clinical trials demonstrating efficacy of new therapies in slowing chronic kidney disease (CKD) progression at varying stages of disease.

RECENT FINDINGS

The TESTING trial has provided high-quality evidence for slowing estimated glomerular filtration rate (eGFR) decline with a reduced-dose glucocorticoid regimen, while demonstrating an improved safety profile. Targeted-release budesonide represents a well tolerated therapy for reducing eGFR decline. Mycophenolate mofetil may reduce CKD progression in some populations, while hydroxychloroquine is efficacious in reducing proteinuria. Sodium-glucose cotransporter (SGLT2) inhibitors and sparsentan are effective therapies for CKD due to IgAN, but should not be used in lieu of disease-modifying immunosuppressive therapy. Many new therapies are approaching readiness for clinical use.

SUMMARY

Numerous therapeutic options now exist and include disease-modifying and nephroprotective drugs. Identifying the right treatment for the right patient is now the clinical challenge and, with new drugs on the horizon, represents the primary unmet research need in this rapidly-developing field.

Efficacy and safety of low-dose corticosteroids combined with leflunomide for progressive IgA nephropathy: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

The effectiveness of immunosuppressive and corticosteroid treatments for Immunoglobulin A (IgA) nephropathy (IgAN) remains thoroughly evaluated. We undertook a meta-analysis to investigate the efficacy and safety of low-dose corticosteroids plus leflunomide for progressive IgA nephropathy.

METHODS

Eligible studies were obtained from PubMed, Embase, and Cochrane Library databases. We also searched the references of the included studies. Our protocol followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist. Eligibility criteria were defined using a PICOS framework.

RESULTS

Our study included three articles presenting 342 patient cases. Findings revealed that low-dose corticosteroids combined with the leflunomide group were effective in relieving urine protein excretion (UPE) [mean difference (MD) = -0.35, 95% confidence interval (CI): -0.41 to -0.30, P < 0.00001] compared with the full-dose corticosteroids group. Regarding serum creatinine (SCr), estimated glomerular filtration rate (eGFR), complete remission rate, and overall response rate, there was no difference between the groups (p > 0.05). Regarding safety, low-dose corticosteroids combined with leflunomide significantly reduced the risk of serious adverse events [odds ratio (OR): 0.11, 95% CI: 0.01 to 0.91, P = 0.04]. Besides, no significant differences were observed between the two groups in the incidence of respiratory infection, abnormal liver function, diarrhea, herpes zoster, alopecia, pruritus, insomnia, pneumonia, diabetes, and urinary tract infection (P > 0.05).

CONCLUSIONS

Low-dose corticosteroids combined with leflunomide are a safe and effective treatment for progressive IgA nephropathy.

TRIAL REGISTRATION

The PROSPERO registration number is CRD42022361883.

Diagnosing and Treating IgAN: Steroids, Budesonide, or Maybe Both?

IgA nephropathy (IgAN), the most common primary glomerulonephritis worldwide, is characterized by a mesangial IgA deposit and a variety of histological lesions, as described by the Oxford classification system. Despite the well-described "four-hit hypothesis", there are still plenty of less or undescribed mechanisms that participate in the disease pathogenesis, such as B-cell priming, which seems to be initiated by different antigens in the intestinal microbiota. Diagnosis of the disease is currently based on kidney biopsy findings, as the sensitivity and specificity of the many serum and urinary biomarkers described so far do not seem to have diagnostic accuracy. Therapeutic strategies consist of the initial step of non-immune medication, aiming to reduce both the intraglomerular pressure and proteinuria to below 0.5 g/day, followed by systemic corticosteroid administration in patients who remain at high risk for progressive chronic kidney disease despite the maximum non-immune treatment. The 6-month systemic corticosteroid treatment reduces proteinuria levels; however, the increased possibility of adverse events and increased relapse rate after treatment raises the need for a new therapeutic approach. Targeted-release budesonide is a therapeutic modality that aims to inhibit disease pathogenetic pathways at early stages; it has minor systemic absorption and proven beneficial effects on renal function and proteinuria. In the present systemic review, the benefits and adverse events of steroids and budesonide are described, and the possibility of combined treatment is questioned in selected cases with active histologic lesions.

An Update on Current Therapeutic Options in IgA Nephropathy

Immunoglobulin A nephropathy (IgAN) remains the leading cause of primary glomerular disease worldwide. Outcomes are poor with high rates of progressive chronic kidney disease and kidney failure, which contributes to global healthcare costs. Although this disease entity has been described, there were no disease-specific treatments until recently, with the current standard of care focusing on optimal supportive measures including lifestyle modifications and optimization of the renin-angiotensin-aldosterone blockade. However, with significant advances in the understanding of the pathogenesis of IgAN in the past decade, and the acceptance of surrogate outcomes for accelerated drug approval, there have been many new investigational agents tested to target this disease. As these agents become available, we envision a multi-pronged treatment strategy that simultaneously targets the consequences of ongoing nephron loss, stopping any glomerular inflammation, inhibiting pro-fibrotic signals in the glomerulus and tubulo-interstitium, and inhibiting the production of pathogenic IgA molecules. This review is an update on a previous review published in 2021, and we aim to summarize the developments and updates in therapeutic strategies in IgAN and highlight the promising discoveries that are likely to add to our armamentarium.

Non-immunosuppressive treatment for IgA nephropathy

BACKGROUND

IgA nephropathy (IgAN) is the most common primary glomerular disease, with approximately 20% to 40% of patients progressing to kidney failure within 25 years. Non-immunosuppressive treatment has become a mainstay in the management of IgAN by improving blood pressure (BP) management, decreasing proteinuria, and avoiding the risks of long-term immunosuppressive management. Due to the slowly progressive nature of the disease, clinical trials are often underpowered, and conflicting information about management with non-immunosuppressive treatment is common. This is an update of a Cochrane review, first published in 2011.

OBJECTIVES

To assess the benefits and harms of non-immunosuppressive treatment for treating IgAN in adults and children. We aimed to examine all non-immunosuppressive therapies (e.g. anticoagulants, antihypertensives, dietary restriction and supplementation, tonsillectomy, and herbal medicines) in the management of IgAN.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to December 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of non-immunosuppressive agents in adults and children with biopsy-proven IgAN were included.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed search results, extracted data and assessed study quality. Results were expressed as mean differences (MD) for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI) using random-effects meta-analysis. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

This review includes 80 studies (4856 participants), of which 24 new studies (2018 participants) were included in this review update. The risk of bias within the included studies was mostly high or unclear for many of the assessed methodological domains, with poor reporting of important key clinical trial methods in most studies. Antihypertensive therapies were the most examined non-immunosuppressive therapy (37 studies, 1799 participants). Compared to placebo or no treatment, renin-angiotensin system (RAS) inhibition probably decreases proteinuria (3 studies, 199 participants: MD - 0.71 g/24 h, 95% CI -1.04 to -0.39; moderate certainty evidence) but may result in little or no difference to kidney failure or doubling of serum creatinine (SCr), or complete remission of proteinuria (low certainty evidence). Death, remission of haematuria, relapse of proteinuria or > 50% increase in SCr were not reported. Compared to symptomatic treatment, RAS inhibition (3 studies, 168 participants) probably decreases proteinuria (MD -1.16 g/24 h, 95% CI -1.52 to -0.81) and SCr (MD -9.37 µmol/L, 95% CI -71.95 to -6.80) and probably increases creatinine clearance (2 studies, 127 participants: MD 23.26 mL/min, 95% CI 10.40 to 36.12) (all moderate certainty evidence); however, the risk of kidney failure is uncertain (1 study, 34 participants: RR 0.20, 95% CI 0.01 to 3.88; very low certainty evidence). Death, remission of proteinuria or haematuria, or relapse of proteinuria were not reported. The risk of adverse events may be no different with RAS inhibition compared to either placebo or symptomatic treatment (low certainty evidence). In low certainty evidence, tonsillectomy in people with IgAN in addition to standard care may increase remission of proteinuria compared to standard care alone (2 studies, 143 participants: RR 1.90, 95% CI 1.45 to 2.47) and remission of microscopic haematuria (2 studies, 143 participants: RR 1.93, 95% CI 1.47 to 2.53) and may decrease relapse of proteinuria (1 study, 73 participants: RR 0.70, 95% CI 0.57 to 0.85) and relapse of haematuria (1 study, 72 participants: RR 0.70, 95% CI 0.51 to 0.98). Death, kidney failure and a > 50% increase in SCr were not reported. These trials have only been conducted in Japanese people with IgAN, and the findings' generalisability is unclear. Anticoagulant therapy, fish oil, and traditional Chinese medicines exhibited small benefits to kidney function in patients with IgAN when compared to placebo or no treatment. However, compared to standard care, the kidney function benefits are no longer evident. Antimalarial therapy compared to placebo in one study reported an increase in a > 50% reduction of proteinuria (53 participants: RR 3.13 g/24 h, 95% CI 1.17 to 8.36; low certainty evidence). Although, there was uncertainty regarding adverse events from this study due to very few events.

AUTHORS' CONCLUSIONS

Available RCTs focused on a diverse range of interventions. They were few, small, and of insufficient duration to determine potential long-term benefits on important kidney and cardiovascular outcomes and harms of treatment. Antihypertensive agents appear to be the most beneficial non-immunosuppressive intervention for IgAN. The antihypertensives examined were predominantly angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. The benefits of RAS inhibition appear to outweigh the harms in patients with IgAN. The certainty of the evidence of RCTs demonstrating a benefit of tonsillectomy to patients with Japanese patients with IgAN was low. In addition, these findings are inconsistent across observational studies in people with IgAN of other ethnicities; hence, tonsillectomy is not widely recommended, given the potential harm of therapy. The RCT evidence is insufficiently robust to demonstrate efficacy for the other non-immunosuppressive treatments evaluated here.

The Treatment of Primary IgA Nephropathy: Change, Change, Change

IgA nephropathy (IgAN) is the most common glomerular disease in the world. However, the approach to treatment remains controversial. There has been an explosion of clinical trials over the past decade both to further examine corticosteroid use and usher in additional treatment considerations, including 2 newly approved therapies for IgAN. Sodium glucose cotransporter 2 inhibitors are proving to be effective therapy across proteinuric chronic kidney diseases, and IgAN is not likely to be an exception. Further supportive agents are looking highly promising and so are novel agents that specifically focus on the pathophysiology of this disease, including endothelin blockade, complement inhibition, and B-cell targeted strategies. We suggest a present-day approach to treatment of individuals with IgAN, expose the limitations in our knowledge, and discuss new treatments that may arise, hoping they come with evidence about optimal utilization. Change appears to be inevitable for our approach to the treatment of IgA nephropathy. This is truly an exciting and optimistic time.

Use of corticosteroids in Norwegian patients with immunoglobulin a nephropathy progressing to end-stage kidney disease: a retrospective cohort study

BACKGROUND

Despite several clinical trials, the use of corticosteroid therapy for treating immunoglobulin A nephropathy (IgAN) remains controversial. We aimed to describe the use of corticosteroid therapy combined with supportive therapy in Norwegian patients with IgAN who had progressed to end-stage kidney disease.

METHODS

We conducted a retrospective cohort study using data from the Norwegian Renal Registry. Overall, 143 patients with primary IgAN who progressed to end-stage kidney disease were divided into two groups: the corticosteroid group, who had been treated with corticosteroids and supportive therapy, and the non-corticosteroid group, which had underwent only supportive therapy. The kidney function, time to end-stage kidney disease, and adverse effects were described. The observation period lasted from the diagnostic kidney biopsy until the initiation of kidney replacement therapy.

RESULTS

Of the 143 included patients, 103 underwent supportive therapy alone, and 40 were treated with corticosteroids. Most patients (94%) were treated with renin-angiotensin-system blockade, and all patients reached end-stage kidney disease after a median of 5 years (interquartile range; 2-9 years). Time from diagnosis until end-stage kidney disease was similar in the two study groups (p = 0.98). During 6 months of corticosteroid therapy, median eGFR declined from 21 (interquartile range; 13-46) mL/min/1.73 m2 to 20 (interquartile range; 12-40) mL/min/1.73 m2, and median proteinuria decreased from 5.5 g/24 h to 3.0 g/24 h. Most patients (87.5%) treated with corticosteroids reported adverse events. In our linear regression analysis investigating the time to ESKD, we found that age (β = -0.079, p = 0.008) and proteinuria at diagnosis (β = -0.50, p = 0.01) exhibited statistically significant associations with a delay in the progression to ESKD.

CONCLUSIONS

In this cohort of Norwegian patients with IgAN, corticosteroid therapy did not affect the time from diagnosis until end-stage kidney disease among a cohort of patients who all reached end-stage kidney disease. The treatment was also associated with adverse effects.

Treatment of IgA Nephropathy: A Rapidly Evolving Field

The pivotal event in the pathophysiology of IgA nephropathy is the binding of circulating IgA-containing immune complexes to mesangial cells, with secondary glomerular and tubulointerstitial inflammation and fibrosis. The paramount difficulty in the management of IgA nephropathy is the heterogeneity in its clinical presentation and prognosis, requiring an individualized treatment approach. Goal-directed supportive care remains the bedrock of therapy for all patients, regardless of risk of progression. Sodium-glucose transporter 2 inhibitors and sparsentan should be integral to contemporary supportive care, particularly in patients with chronic kidney damage. Pending the development of reliable biomarkers, it remains a challenge to identify patients prone to progression due to active disease and most likely to derive a net benefit from immunosuppression. The use of clinical parameters, including the degree of proteinuria, the presence of persistent microscopic hematuria, and the rate of eGFR loss, combined with the mesangial hypercellularity, endocapillary hypercellularity, segmental glomerulosclerosis, tubular atrophy/interstitial fibrosis, crescents score, is currently the best approach. Systemic glucocorticoids are indicated in high-risk patients, but the beneficial effects wane after withdrawal and come at the price of substantial treatment-associated toxicity. Therapies with direct effect on disease pathogenesis are increasingly becoming available. While targeted-release budesonide has garnered the most attention, anti-B-cell strategies and selective complement inhibition will most likely prove their added value. We propose a comprehensive approach that tackles the different targets in the pathophysiology of IgA nephropathy according to their relevance in the individual patient.

IgA Nephropathy: Beyond the Half-Century

In 1968, Jean Berger first introduced the medical world to IgA nephropathy (IgAN). Fifty-five years later, its pathogenesis is still unclear, but treatments such as renin-angiotensin-aldosterone system inhibitors (RAAS-Is), tonsillectomies, and glucocorticoids are currently used worldwide. There have been great strides in the past 20 years since the discoveries of the specific dysregulation of mucosal immunity, galactose-deficient IgA1 (Gd-IgA1), and Gd-IgA1 immune complexes in patients with IgAN. According to these findings, a multi-hit hypothesis was developed, and this multi-hit hypothesis has provided several putative therapeutic targets. A number of novel agents, including molecularly targeted drugs for targets such as APRIL, plasma cells, complement systems, and endothelin, are undergoing clinical trials. Some candidate drugs have been found to be effective, with minimal side effects. Over half a century after the discovery of IgAN, these therapies will soon be available for clinical use.

IgA nephropathy in adults-treatment standard

Immunoglobulin A nephropathy (IgAN) is the most common primary form of glomerular disease worldwide and carries a high lifetime risk of kidney failure. The underlying pathogenesis of IgAN has been characterized to a sub-molecular level; immune complexes containing specific O-glycoforms of IgA1 are central. Kidney biopsy remains the gold-standard diagnostic test for IgAN and histological features (i.e. MEST-C score) have also been shown to independently predict outcome. Proteinuria and blood pressure are the main modifiable risk factors for disease progression. No IgAN-specific biomarker has yet been validated for diagnosis, prognosis or tracking response to therapy. There has been a recent resurgence of investigation into IgAN treatments. Optimized supportive care with lifestyle interventions and non-immunomodulatory drugs remains the backbone of IgAN management. The menu of available reno-protective medications is rapidly expanding beyond blockade of the renin-angiotensin-aldosterone system to include sodium-glucose cotransporter 2 and endothelin type A receptor antagonism. Systemic immunosuppression can further improve kidney outcomes, although recent randomized controlled trials have raised concerns regarding infectious and metabolic toxicity from systemic corticosteroids. Studies evaluating more refined approaches to immunomodulation in IgAN are ongoing: drugs targeting the mucosal immune compartment, B-cell promoting cytokines and the complement cascade are particularly promising. We review the current standards of treatment and discuss novel developments in pathophysiology, diagnosis, outcome prediction and management of IgAN.

Associations of corticosteroid therapy and tonsillectomy with kidney survival in a multicenter prospective study for IgA nephropathy

Efficacy of systemic corticosteroid therapy (CS) for long-term kidney survival in patients with IgA nephropathy (IgAN) is controversial. Therefore, prospective studies evaluating targeted therapies to lymphatic tissues in mucosal immune system responsible for production of nephritogenic IgA have been desired worldwide. Here, we aimed to evaluate the associations of CS and combination therapy of CS and tonsillectomy (CS + Tx) with kidney survival, using database from a nationwide multicenter prospective cohort study on IgAN. Primary outcome was a 50% increase in serum creatinine from baseline or dialysis induction. The analysis included 941 patients (CS/CS + Tx/non-CS 239/364/338), 85 (9.0%) of whom reached outcomes during median follow-up of 5.5 (interquartile range 2.0-8.0) years. On overlap weighting analysis with balanced baseline characteristics, CS and CS + Tx were associated with lower risk of kidney events when compared with non-CS (hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.29-0.88 and HR 0.20, 95%CI 0.09-0.44, respectively). Notably, when compared with the CS, CS + Tx was associated with a lower risk of kidney events (HR 0.40, 95%CI 0.18-0.91). Present study demonstrated, keeping with favorable association of systemic CS with kidney survival, concurrent tonsillectomy as one of targeted interventions to lymphatic tissues may provide additional improvement to kidney survival in patients with IgAN.

Immunosuppression versus Supportive Care on Kidney Outcomes in IgA Nephropathy in the Real-World Setting

BACKGROUND

The efficacy of immunosuppression in the management of immunoglobulin A (IgA) nephropathy remains highly controversial. The study was conducted to assess the effect of immunosuppression, compared with supportive care, in the real-world setting of IgA nephropathy.

METHODS

A cohort of 3946 patients with IgA nephropathy, including 1973 new users of immunosuppressive agents and 1973 propensity score-matched recipients of supportive care, in a nationwide register data from January 2019 to May 2022 in China was analyzed. The primary outcome was a composite of 40% eGFR decrease of the baseline, kidney failure, and all-cause mortality. A Cox proportional hazard model was used to estimate the effects of immunosuppression on the composite outcomes and its components in the propensity score-matched cohort.

RESULTS

Among 3946 individuals (mean [SD] age 36 [10] years, mean [SD] eGFR 85 [28] ml/min per 1.73 m 2 , and mean [SD] proteinuria 1.4 [1.7] g/24 hours), 396 primary composite outcome events were observed, of which 156 (8%) were in the immunosuppression group and 240 (12%) in the supportive care group. Compared with supportive care, immunosuppression treatment was associated with 40% lower risk of the primary outcome events (adjusted hazard ratio, 0.60; 95% confidence interval, 0.48 to 0.75). Comparable effect size was observed for glucocorticoid monotherapy and mycophenolate mofetil alone. In the prespecified subgroup analysis, the treatment effects of immunosuppression were consistent across ages, sexes, levels of proteinuria, and values of eGFR at baseline. Serious adverse events were more frequent in the immunosuppression group compared with the supportive care group.

CONCLUSIONS

Immunosuppressive therapy, compared with supportive care, was associated with a 40% lower risk of clinically important kidney outcomes in patients with IgA nephropathy.

IgA Nephropathy: Current Treatment and New Insights

IgA Nephropathy (IgAN) is the most common cause of primary glomerulonephritis worldwide. Despite the histopathologic hallmark of mesangial IgA deposition, IgAN is a heterogenous autoimmune disease not only in terms of clinical presentation but also in long-term disease progression. The pathogenesis of the disease is complex and includes the generation of circulating IgA immune complexes with chemical and biological characteristics that favor mesangial deposition and reaction to mesangial under-glycosylated IgA1 accumulation, which leads to tissue injury with glomerulosclerosis and interstitial fibrosis. Patients with proteinuria over 1 g, hypertension, and impaired renal function at diagnosis are considered to be at high risk for disease progression and end-stage kidney disease (ESKD). Glucocorticoids have been the mainstay of treatment for these patients for years, but without long-term benefit for renal function and accompanied by several adverse events. A better understanding of the pathophysiology of IgAN in recent years has led to the development of several new therapeutic agents. In this review, we summarize the current therapeutic approach for patients with IgAN as well as all novel investigational agents.

IgA nephropathy: a review of existing and emerging therapies

IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide. Recently, there have been multiple advances in the understanding of IgAN pathophysiology and therapeutic options. Despite the advent of new treatment options, individual risk stratification of the disease course and choosing the best treatment strategy for the patient remains challenging. A multitude of clinical trials is ongoing, opening multiple opportunities for enrollment. In this brief review we discuss the current approach to the management of IgAN and highlight the ongoing clinical trials.

An update on corticosteroid treatment for IgA nephropathy

PURPOSE OF REVIEW

The use of corticosteroids to treat IgA nephropathy (IgAN) has been limited by many controversies related to uncertain benefit and safety concerns. Recent trials have tried to address these limitations.

RECENT FINDINGS

After being paused because of an excess of adverse events in the full-dose steroid arm, the TESTING trial compared a reduced dose of methylprednisolone to placebo in patients with IgAN after optimization of supportive therapy. Steroid treatment was associated with a significant reduction in the risk of a 40% decline in estimated glomerular filtration rate (eGFR), kidney failure and kidney death as well as a sustained decrease in proteinuria compared with placebo. Serious adverse events were more frequent with the full dose regimen but less common in the reduced dose regimen. A phase III trial evaluating a new formulation of targeted-release budesonide showed a significant reduction in short-term proteinuria and has resulted in accelerated FDA approval for use in the United States. In a subgroup analysis of DAPA-CKD trial, sodium-glucose transport protein 2 inhibitors reduced the risk of kidney function decline in patients who have completed or are not eligible for immunosuppression.

SUMMARY

Both reduced-dose corticosteroids and targeted-release budesonide are new therapeutic options that can be used in patients with high-risk disease. More novel-targeted therapies with a better safety profile are currently under investigations.

Corticosteroid Therapy in Immunoglobulin A Nephropathy: A Friend or Foe?

BACKGROUND

The administration of corticosteroids in addition to supportive care to delay progressive immunoglobulin A nephropathy (IgAN), the most common primary glomerulonephritis worldwide, remains controversial. This is partly due to the paucity of well-designed randomized controlled trials and well-known corticosteroid-related side effects. As a result, clinical equipoise in corticosteroid therapy exists depending on geographical regions and the clinician's preference.

SUMMARY

Better understanding around the pathogenesis of IgAN has prompted several clinical trials exploring the effects of immunosuppressive agents including corticosteroids. Earlier studies of corticosteroids were limited by suboptimal study designs, inadequate implementation of standard of care, and inconsistent adverse event data collection. Two well-designed, adequately powered, multi-centre randomized controlled trials, the STOP-IgAN and TESTING studies, have reported contrasting kidney outcomes that have further fuelled the clinical conundrum regarding the efficacy of corticosteroids. Both studies independently reported greater adverse events with corticosteroids. A novel targeted release formulation of budesonide, which has been hypothesized to reduce the adverse events associated with systemic corticosteroids, has shown promising results in the Phase 3 NefigaRD trial. Studies of treatments targeting B cells and the complement cascade are currently underway, and early data appear encouraging. This review provides an overview of the current literature around the understanding of the pathomechanisms and benefits and harm of corticosteroid use in IgAN.

KEY MESSAGES

Recent evidence suggests the use of corticosteroids in a selected cohort of people with IgAN at high risk of disease progression can improve kidney outcomes but comes with an associated risk of treatment-related adverse events, particularly with higher doses. Management decisions should therefore follow an informed patient-clinician discussion.

IgA nephropathy: an overview of drug treatments in clinical trials

INTRODUCTION

IgA nephropathy (IgAN) is the commonest primary glomerulonephritis worldwide and may progress to end-stage kidney disease (ESKD) within a 10-20 year period. Its slowly progressive course has made clinical trials challenging to perform, however the acceptance of proteinuria reduction as a surrogate end point has significantly improved the feasibility of conducting clinical trials in IgAN, with several novel and repurposed therapies currently undergoing assessment. Already, interim results are demonstrating value to some of these, offering great hope to those with IgAN.

AREAS COVERED

This review explores the rationale, candidates, clinical precedents, and trial status of therapies that are currently or have recently been evaluated for efficacy in IgAN. All IgAN trials registered with the U.S. National Library of Medicine; ClinicalTrials.gov were reviewed.

EXPERT OPINION

For the first time, effective treatment options beyond supportive care are becoming available for those with IgAN. This is the culmination of commendable international efforts and signifies a new era for those with IgAN. As more therapies become available, future challenges will revolve around deciding which treatments are most appropriate for individual patients, which is likely to push IgAN into the realm of precision medicine.

Meta-Analysis of the Effectiveness and Safety of Glucocorticoid for the Treatment of IgA Kidney Disease

Purpose

To explore the effect of glucocorticoid on immune globulin A (IgA) nephropathy by meta-analysis.

Method

Search the data and literature libraries of ScienceDirect, EBSCO, Wiley, PubMed, CBMdisc, and CNKI and collect the literature on the treatment of IgA nephropathy with glucocorticoids as randomized controlled trials published at home and abroad from 1995 to 2021. The standardized mean difference (SMD) and 95% confidence interval (CI) were calculated by fixed-effects model. RevMan 5.0 software was used for meta-analysis of the subgroups of overall curative effect, different degree of proteinuria, different course of treatment, different creatinine level, and combined ACEI.

Result

① The overall efficacy of glucocorticoid in the treatment of IgA nephropathy was better than that in the control group (P = 0.00001). ② The efficacy of glucocorticoid treatment in patients with IgA nephropathy with proteinuria greater than 1.50 g/d and less than 1.50 g/d was better than that in the control group (P < 0.01). ③ For IgA nephropathy patients with serum creatinine less than 1.50 mg/dl, the curative effect of glucocorticoid treatment was better than that of the control group (P < 0.01). ④ The effects of short-term treatment (<1 year) and long-term treatment (≥1 year) with glucocorticoid were better than those in the control group (P < 0.01). ⑤ The effect of hormone combined with ACEI drugs on IgA nephropathy was more significant (P < 0.01).

Conclusion

The overall efficacy of glucocorticoid in the treatment of IgA nephropathy is accurate. Hormone treatment is effective for different degrees of IgA nephropathy. Considering that there is no significant effect on the efficacy of different courses of treatment, it is suggested that the course of hormone treatment can be appropriately shortened. Hormone combined with angiotensin-converting enzyme inhibitors (ACEI) can reduce proteinuria more effectively than ACEI drugs alone.

Efficacy of Glucocorticoids and Glucocorticoid-Induced Hyperglycaemia in Renal Disease: A Meta-Analysis of Randomized Controlled Trials

Background

Glucocorticoids are the most effective anti-inflammatory and immunosuppressive drugs used to treat patients with renal disease. This study pooled the current evidence of the efficacy of Glucocorticoids and Glucocorticoid-induced hyperglycaemia in renal disease.

Methods

We conducted a systematic literature search on PubMed, Cochrane Central, and Web of Science for relevant randomized controlled trials (RCTs) up to September 1, 2021. The meta-analysis, sensitivity analysis and bias analysis were performed using Review Manager 5. 3.

Results

In this study, seven RCTs with 797 patients were included in our analysis. The analysis revealed that glucocorticoids had a certain alleviating effect on the reduction of renal function. (risk ratio [RR] 0.49 95% confidence interval [Cl] 0. 28 to 0.85, p =0.01) and reduction of proteinuria (weight mean difference [WMD] -0.43; 95% CI -0.57 to-0.28) when compared with the control group. Patients receiving glucocorticoids therapy did not have an increased risk of developing new-onset diabetes mellitus or impaired glucose tolerance. (RR 3.76 95% CI 0.54 to 26.10, p =0.18). For other safety outcomes, glucocorticoids therapy did not increase risk of respiratory infections (RR 1.63, 95% CI 0. 69to3. 89, p =0.27) and Gastrointestinal SAEs is relatively controversial (RR 1.10, 95% CI 0.32 to 3.79, p =0.88). Discussion. In conclusion, current clinical evidence indicates that glucocorticoids is efficacious and safe to renal disease compared with control. Further research comparing long-term glucocorticoids use is needed.

Immunosuppressants or corticosteroids compared with supportive therapy: a systematic review and meta-analysis on the efficacy and safety for IgA nephropathy treatment

Background

Corticosteroids or immunosuppressants and supportive treatment in reducing the risk of proteinuria and end-stage kidney disease (ESKD) in immunoglobulin A (IgA) nephropathy (IgAN) patients were still controversial. The purpose of this meta-analysis was to evaluate the efficacy and safety of immunosuppressants or corticosteroids compared with supportive therapy for treatment of IgAN in order to provide guidance for clinical practice.

Methods

We conducted an online search in PubMed, Embase, Cochrane Library, and Web of Science databases to collect randomized control trials (RCTs) about the efficacy and safety of immunosuppressants or corticosteroids compared with supportive therapy for treatment of IgA for relevant literature published from the databases' inception to August 21, 2021. The Cochrane risk assessment tool was used to assess the risk of bias in the included studies and analyzed by Revman 5.4 software, and Stata 15.0 statistical software was adopted for meta-analysis.

Results

A total of 10,622 related studies were retrieved, and 11 RCTs were finally included in the meta-analysis, with a total sample size of 809 cases. The primary outcome measures for immunosuppressants or corticosteroids were better than those for supportive therapy: proteinuria [weighted mean difference (WMD) =-0.54, 95% confidence interval (CI): -0.63, -0.44, Z =10.79, P<0.001] and ESKD [relative risk (RR) =0.189, 95% CI: 0.059, 0.605, Z =2.81, P=0.005]. The secondary outcome measures were also better than that for supportive treatment: glomerular filtration rate [standardized mean difference (SMD) =0.32, 95% CI: 0.09, 0.54, Z =2.48, P=0.013]. The incidence of adverse reactions was consistent with that of supportive treatment, and the difference was not statistically significant (RR =1.06, 95% CI: 0.71, 1.59, Z =0.28, P=0.777).

Discussion

Current evidence shows that immunosuppressants and corticosteroids can significantly reduce the risk of proteinuria and ESKD in IgAN patients. Due to limited quality and quantity of the included studies, more high-quality studies are need to verify above conclusion. In addition, we hope that more rationally designed multicenter RCTs that are not limited to short-term treatment outcomes will be conducted in the future.

Effect of Cyclophosphamide and Glucocorticoid Therapy in IgA Nephropathy: A Single-Center Retrospective Analysis

Background

IgA nephropathy (IgAN) is the most common primary glomerulonephritis in adults, which causes ESKD in ≤45% of patients in the long term. The optimal therapeutic approach remains undetermined. In this study, we report the results of a single-center retrospective analysis of patients with IgAN.

Methods

We retrospectively evaluated the therapeutic approach and outcome of all patients at our center with biopsy-proven IgAN between 2000 and 2020, focusing on the effect of intravenous cyclophosphamide therapy combined with glucocorticoids ("immunosuppressive therapy group"). The control group received standard supportive care.

Results

Patients in the immunosuppressive therapy group had worse kidney function before the initiation of therapy, as indicated by higher serum creatinine, more proteinuria, and a higher degree of hematuria than the control group; they also displayed a higher body mass index. The Oxford classification of IgA nephropathy (MEST-C score) suggested more inflammatory activity in the immunosuppressive therapy group, including more crescents and endocapillary hypercellularity. During the follow-up, proteinuria and hematuria decreased in both groups, and to a significantly greater extent in the immunosuppressive therapy group. Cyclophosphamide treatment significantly improved kidney function as determined by the fold-change of eGFR during the observation period. The number of infections and hospitalizations did not differ, but the incidence of diabetes was increased in the immunosuppressive therapy group.

Conclusions

This study suggests immunosuppressive therapy with cyclophosphamide combined with glucocorticoids improves kidney function, proteinuria, and hematuria. The therapy was safe for infectious complications, but was associated with an increased incidence of diabetes, which might be attributable in part to the use of steroids in patients with a higher body mass index at baseline. Although immunosuppressive therapy in IgAN remains controversial, our findings suggest that at least some patients benefit from more aggressive therapy.

Corticosteroids and mycophenolic acid analogs in IgA nephropathy with progressive decline in kidney function

Background

A randomized controlled trial (RCT) demonstrated a beneficial effect of corticosteroids (CS) plus cyclophosphamide followed by azathioprine in progressive IgA nephropathy (IgAN). Although treatment with CS and mycophenolic acid analogs (MPAA) remains controversial in IgAN, there is no information about their effect in progressive IgAN.

Methods

Patients with progressive IgAN, defined by a decrease in estimated glomerular filtration rate (eGFR) of at least 10 ml/min/1.73 m2 in the 12 months prior to the start of treatment, proteinuria ≥ 0.75 g/24h despite maximum tolerated doses of renin-angiotensin system blockers (RASB) and persistent hematuria, who had received treatment with CS+MPAA were included in this retrospective study. The main outcome was the difference between the eGFR slope from the start of treatment with CS+MPAA to the last visit with this treatment with respect to the eGFR slope during the 12 months prior to start of treatment.

Results

Twenty-five patients were included in the study. Mean duration of CS+MPAA treatment was 24.7±15.2 months. In the 12 months prior to treatment the median rate of kidney function decline was -23 [-32 to -16] ml/min/1.73 m2 per year. After the onset of treatment, the median eGFR slope was +5 [+3 to +9] ml/min/1.73 m2 per year (P = 0.001 with respect to the 12 months prior to treatment). Proteinuria decreased from 1.8 (1.0-2.5) g/day at baseline to 0.6 (0.3-1.2) g/day at the end of treatment (P = 0.01) and hematuria disappeared in 40% of the patients. There were no serious adverse effects requiring treatment discontinuation.

Conclusions

CS + MPAA is an effective treatment in IgAN patients with a sustained decline in kidney function accompanied by persistent proteinuria and hematuria despite optimized conservative treatment. Prospective studies are needed to confirm these results.

Current treatment of IgA nephropathy

IgA nephropathy (IgAN) is the most common type of glomerulonephritis in Asia and the Western world. In most patients, it follows an asymptomatic to oligosymptomatic course and GFR loss, if any, is slow. The mainstay of therapy therefore is optimized supportive care, i.e., measures that lower blood pressure, reduce proteinuria, minimize lifestyle risk factors, and otherwise help to reduce non-specific insults to the kidneys. The value of immunosuppression has become controversial and if at all, systemic high-dose corticosteroid therapy should be considered for a few months taking into account patient characteristics that would caution against or preclude such therapy. In addition, adverse events related to corticosteroid therapy markedly increase as GFR declines. Beyond corticosteroids, there is little evidence that any additional immunosuppression is helpful, with the exception of mycophenolate mofetil in patients of Asian descent. A considerable number of clinical trials ranging from enteric coated budesonide to blockade of B-cell function to complement inhibitors are currently ongoing and will hopefully allow a more targeted therapy of high-risk patients with progressive IgAN in the future.

Reduction in proteinuria after immunosuppressive therapy and long-term kidney outcomes in patients with immunoglobulin A nephropathy

BACKGROUND/AIMS

Despite controversy regarding the benefits of immunosuppressive therapy in immunoglobulin A nephropathy (IgAN), clinical outcomes may vary depending on the patient's responsiveness to this therapy. This study evaluated long-term kidney outcomes according to the extent of proteinuria reduction after immunosuppression in IgAN patients.

METHODS

Among 927 patients with biopsy-proven IgAN, 127 patients underwent immunosuppression. Time-averaged urine protein-creatinine ratio before and within 1 year after start of immunosuppression were calculated, and responsiveness to immunosuppression was assessed as the reduction of proteinuria between the two periods. Patients were classified into tertiles according to the extent of proteinuria reduction. We compared the slopes of estimated glomerular filtration rate (eGFR) decline using a linear mixed model, and estimated hazard ratios (HRs) for disease progression (defined as development of a ≥ 30% decline in eGFR or end-stage renal disease) using a Cox proportional hazard model.

RESULTS

Median extent of proteinuria reduction was -2.1, -0.9, and -0.2 g/gCr in the first, second, and third tertiles, respectively. There were concomitant changes in the slopes of annual eGFR decline: -2.03, -2.44, and -4.62 mL/min/1.73 m2 among the first, second, and third tertiles, respectively. In multivariable Cox analysis, the HRs (95% confidence intervals) for disease progression were 0.30 (0.12 to 0.74) in the first tertile and 0.70 (0.34 to 1.45) in the second tertile compared with the thirdtertile.

CONCLUSION

This study showed that greater proteinuria reduction after immunosuppression was associated with a lower risk of disease progression in patients with IgAN, suggesting that responsiveness to immunosuppression may be an important determinant of kidney outcomes.

Management of IgA Vasculitis with Nephritis

Immunoglobulin A (IgA) vasculitis (IgAV), previously called Henoch-Schönlein purpura, is characterized by IgA-dominant immune deposits affecting small vessels and often involves the skin, gastrointestinal tract, joints, and kidneys. IgAV is the most common cause of systemic vasculitis in children. The long-term prognosis is dependent on renal involvement: IgAV with nephritis (IgAVN) can progress to renal failure. IgAVN is an inflammatory disease, providing a rationale for the use of corticosteroids. However, data supporting the use of corticosteroids in patients with established IgAVN of any severity remain limited, although most clinicians use them. Even in patients with severe forms of IgAVN, methylprednisolone pulses added to oral corticosteroids appears to improve renal outcomes. Considering the multihit hypothesis for the pathogenesis of IgAVN, involving many other immune agents, there is a strong rationale for the use of other immunosuppressive drugs in patients with IgAVN, including mycophenolic acid, cyclophosphamide, rituximab, calcineurin inhibitors, and complement inhibitors. Thus, these immunosuppressive treatments have also been evaluated in IgAVN, usually in corticosteroid-dependent or corticosteroid-resistant forms and in small retrospective studies. However, their efficacy has not been proven. Thus, the risk of progression to renal failure and the ongoing debate about the best management of IgAVN justifies the interest in investigating and identifying treatments that can potentially preserve renal function in patients with IgAVN. This review reports on the efficacy of the different drugs currently used for the treatment of IgAVN in adults and children.

Leflunomide plus low-dose prednisone in patients with progressive IgA nephropathy: a multicenter, prospective, randomized, open-labeled, and controlled trial

Background

Immunoglobulin A nephropathy (IgAN) is the most common cause of glomerulonephritis worldwide, and the optimal approach to its treatment remains a significant challenge.

Methods

We did a prospective, randomized, open-labeled, multicenter, controlled trial, comprised of 3-month run-in, 12-month treatment, and 12-month follow-up phases. After 3-month run-in phase, patients with biopsy-confirmed IgAN at risk of progression were randomly allocated to LEF plus low-dose prednisone (LEF + prednisone group) or conventionally accepted-dose prednisone [prednisone(alone) group] Our primary outcome was 24-h urine protein excretion (UPE) and secondary outcomes were serum albumin (sALB), serum creatinine (Scr), and eGFR. Safety was evaluated in all patients who received the trial medications.

Results

One hundred and eight patients [59 in LEF + prednisone group, 49 in prednisone (alone) group]were enrolled and finished their treatment and follow-up periods. There is no significant difference in the baseline level between the two groups. Compared with baseline, both groups showed a significant decrease in 24-h UPE (p < 0.01) and increase in sALB (p < 0.01), with stable Scr and eGFR throughout the 12-month treatment period. What’s more, these effects were sustained through the 12-month follow-up period. However, there was no difference in 24-h UPE, sALB, Scr, and eGFR between the two groups (p > 0.05). At 12 months, a difference in overall response rate, relapsing rate, and incidence of adverse events between the two groups was not significant.

Conclusions

The efficacy and safety of LEF plus low-dose prednisone and conventionally accepted-dose prednisone in the treatment of progressive IgAN are comparable.

An Update on the Current State of Management and Clinical Trials for IgA Nephropathy

IgA nephropathy remains the most common primary glomerular disease worldwide. It affects children and adults of all ages, and is a leading cause of end-stage kidney disease, making it a considerable public health issue in many countries. Despite being initially described over 50 years ago, there are still no disease specific treatments, with current management for most patients being focused on lifestyle measures and renin-angiotensin-aldosterone system blockade. However, significant advances in the understanding of its pathogenesis have been made particularly over the past decade, leading to great interest in developing new therapeutic strategies, and a significant rise in the number of interventional clinical trials being performed. In this review, we will summarise the current state of management of IgAN, and then describe major areas of interest where new therapies are at their most advanced stages of development, that include the gut mucosal immune system, B cell signalling, the complement system and non-immune modulators. Finally, we describe clinical trials that are taking place in each area and explore future directions for translational research.

Efficacy and safety of immunosuppressive therapies in the treatment of high-risk IgA nephropathy: A network meta-analysis

BACKGROUND

IgA nephropathy (IgAN) is one of the significant contributing factors of end-stage renal disease (ESRD). It is reported that over half of patients with IgAN accompany multiple high-risk factors, which increase the risk of ESRD progression. Studies have shown that immunosuppressive agents were beneficial in high-risk IgAN, but the efficacy and safety have not been fully demonstrated yet. The present study aims to elucidate the efficacy of commonly used immunosuppressants in high-risk IgAN and their relative safety profiles via a network meta-analysis strategy.

METHODS

Randomized controlled trials (RCTs) eligible for this network meta-analysis were included to evaluate the efficacy and safety of different immunosuppressants for high-risk IgAN. Main outcomes and measures include incidence of renal composite end point, the rate of total remission, adverse events, and proteinuria. Besides, subgroup analysis and cluster analysis were carried out.

RESULTS

This network meta-analysis of 37 RCTs involving 3012 participants found that Mycophenolate mofetil (MMF) combined with corticosteroids (CS) was superior to other interventions in end point events and proteinuria. Cyclosporine A (CsA) plus CS was the best option for clinical remission rate, and supportive care (SC) was the safest treatment. Cluster analysis showed that MMF+CS and Leflunomide (LEF)+CS were best protocols in efficacy and safety. Subgroup analysis indicated the best benefits of MMF were presented among the Asian population, and the benefits increased with the increase of follow-up duration. The effect of Cyclophosphamide (CTX) +CS on crescent IgAN was better than that of other risk factors. Moreover, the increasing follow-up duration was negatively associated with the effect.

CONCLUSIONS

MMF+CS and LEF+CS appear to serve as the best choice for treating high-risk IgAN than other immunosuppressive therapies.

Long-term safety and efficacy of hydroxychloroquine in patients with IgA nephropathy: a single-center experience

BACKGROUND

Hydroxychloroquine (HCQ) has been used as a supportive therapy for IgA nephropathy (IgAN). We aimed to determine the long-term efficacy and safety of HCQ therapy in patients with IgAN.

METHODS

A total of 180 patients with IgAN who had received HCQ therapy for at least 1 year were enrolled in this study. The changes in proteinuria and the estimated glomerular filtration rate (eGFR) were analyzed during the follow-up period.

RESULTS

The level of proteinuria decreased from 1.69 [1.24, 2.30] to 1.01 [0.59, 1.74] g/day (- 37.58 [- 57.52, 8.24] %, P < 0.001) at 12 months and to 1.00 [0.59, 1.60] g/day (- 55.30 [- 71.09, - 3.44] %, P < 0.001) at 24 months. There was no significant change in the eGFR of these patients at 12 months (65.82 ± 25.22 vs. 63.93 ± 25.96 ml/min/1.73 m², P = 0.411); however, the eGFR decreased from 65.82 ± 25.22 to 62.15 ± 25.81 ml/min/1.73 m² at 24 months (P = 0.003). The cumulative frequency of all patients with a 50% decrease in proteinuria was 72.78% at 12 months. Sixty (33.3%) patients changed to corticosteroid therapy during the follow-up period. No serious adverse effects were documented during HCQ treatment.

CONCLUSIONS

HCQ effectively and safely reduces proteinuria in IgAN patients with different levels of eGFR, supporting the maintenance of stable kidney function in the long term.

Long-term safety and efficacy of hydroxychloroquine in patients with IgA nephropathy: a single-center experience

BACKGROUND

Hydroxychloroquine (HCQ) has been used as a supportive therapy for IgA nephropathy (IgAN). We aimed to determine the long-term efficacy and safety of HCQ therapy in patients with IgAN.

METHODS

A total of 180 patients with IgAN who had received HCQ therapy for at least 1 year were enrolled in this study. The changes in proteinuria and the estimated glomerular filtration rate (eGFR) were analyzed during the follow-up period.

RESULTS

The level of proteinuria decreased from 1.69 [1.24, 2.30] to 1.01 [0.59, 1.74] g/day (- 37.58 [- 57.52, 8.24] %, P < 0.001) at 12 months and to 1.00 [0.59, 1.60] g/day (- 55.30 [- 71.09, - 3.44] %, P < 0.001) at 24 months. There was no significant change in the eGFR of these patients at 12 months (65.82 ± 25.22 vs. 63.93 ± 25.96 ml/min/1.73 m², P = 0.411); however, the eGFR decreased from 65.82 ± 25.22 to 62.15 ± 25.81 ml/min/1.73 m² at 24 months (P = 0.003). The cumulative frequency of all patients with a 50% decrease in proteinuria was 72.78% at 12 months. Sixty (33.3%) patients changed to corticosteroid therapy during the follow-up period. No serious adverse effects were documented during HCQ treatment.

CONCLUSIONS

HCQ effectively and safely reduces proteinuria in IgAN patients with different levels of eGFR, supporting the maintenance of stable kidney function in the long term.

Efficacy and Safety of Immunosuppressive Monotherapy Agents for IgA Nephropathy: A Network Meta-Analysis

Background: The efficacy and safety of immunosuppressive monotherapy agents were evaluated for immunoglobulin A nephropathy (IgAN) using a network meta-analysis approach. Methods: Randomized controlled trials (RCTs) published prior to October 1, 2019, using immunosuppressive agents for treating IgAN, were systematically searched in PubMed, Embase, Cochrane Library, and Web of Science databases. Relative risks (RRs) or standard mean differences with 95% confidence intervals (CIs) were estimated using the random-effects model. The primary outcomes were clinical remission, end-stage renal disease (ESRD), and serious adverse events (SAEs). The secondary outcomes were urinary protein excretion and serum creatinine. Results: Twenty-five RCTs with 2,005 participants were deemed eligible. Six medications were evaluated: corticosteroids, mycophenolate mofetil (MMF), tacrolimus (TAC), cyclosporine, leflunomide, and hydroxychloroquine (HCQ). Steroids (RR 1.50, 95% CI 1.17-1.93), MMF (RR 2.05, 95% CI 1.15-3.65), TAC (RR 3.67, 95% CI 1.06-12.63), and HCQ (RR 3.25, 95% CI 1.05-10.09) significantly improved clinical remission rates compared to supportive care alone. Only steroids reduced the risk of ESRD (RR 0.35, 95% CI 0.12-0.98); however, there were significantly more SAEs than in the control group (RR 2.90, 95% CI 1.37-6.13). No significantly different effects in serum creatinine levels were found among the therapies. MMF showed no significant improvement in remission when excluding studies with a follow-up of fewer than 2 years in the sensitivity analysis (RR 1.41, 95% CI 0.40-4.92). The effect of TAC in the decrease of proteinuria was reversed after discontinuing medication for 3 months; the long-term effects of HCQ could not be evaluated due to the short follow-up duration. Conclusion: Corticosteroids might induce remission and increase renal survival in IgAN; however, adverse reactions should be taken into consideration. MMF, TAC, and HCQ might improve the remission of proteinuria when treating IgAN, but showed no superiority compared to steroids, and the long-term effects require further study.

Henoch-Schönlein purpura in children: Use of corticosteroids for prevention and treatment of renal disease

QUESTION

A few patients have previously presented to my clinic with palpable purpura, joint inflammation, and severe abdominal pain characteristic of Henoch-Schönlein purpura (HSP). Considering that renal injury is the primary long-term complication of HSP, are corticosteroids effective in preventing or treating renal disease in children with HSP?

ANSWER

Henoch-Schönlein purpura is self-limiting in 94% of children, but permanent renal injury is reported in one-fifth of children with nephritic or nephrotic features. Corticosteroids have been considered as candidates for preventing and treating renal involvement in HSP. There is a moderate level of evidence to suggest corticosteroids are not effective in preventing renal involvement in HSP. However, based on low-level evidence and similarities with primary immunoglobulin A nephropathy, experts recommend corticosteroids in treating renal involvement in HSP to prevent long-term kidney injury. Dose and duration of therapy should be carefully considered in consultation with a pediatric nephrologist.

Efficacy of corticosteroid therapy for IgA nephropathy patients stratified by kidney function and proteinuria

BACKGROUND

Steroid therapy is one of the important therapies for IgA nephropathy (IgAN), but the features of the IgAN patients who have the benefit from this therapy remained unclear.

METHODS

This retrospective observational study, using data of 874 patients with IgAN analyzed the proteinuria and kidney function of IgAN patients who had beneficial effect by steroid therapy. Two advantages of the present study were a large cohort and a long observational period.

RESULTS

Corticosteroid therapy had ameliorated the kidney prognosis [incident rate ratio (IRR) 0.57 (95%CI 0.34-0.92), P = 0.029]. Because of interaction between kidney function and use of corticosteroid (P = 0.047), stratification analysis by kidney function revealed that prognosis of kidney function in IgAN patients whose eGFR was less than 60 ml/min/1.73m² was ameliorated by corticosteroid therapy [IRR 0.50 (95%CI 0.26-0.97), P = 0.015); while, there was no change of kidney prognosis in IgAN patients whose eGFR was above 60 ml/min/1.73 m². To make the target of corticosteroid therapy for IgAN patients more clear, IgAN patients, whose eGFR were less than 60 ml/min/1.73 m², were stratified by proteinuria (1 g/day). In IgAN patients whose eGFR were under 60 ml/min/1.73 m² and whose proteinuria were over 1.0 g/day, corticosteroid therapy seemed to ameliorate kidney function [IRR 0.39 (95%CI 0.19-0.86), P < 0.05]; while, there was obviously no change by corticosteroid therapy in IgAN patients whose eGFR were less than 60 ml/min/1.73 m² and whose proteinuria were less than 1.0 g/day.

CONCLUSION

Our results suggested that steroid therapy was especially effective for IgAN patients whose eGFR was less than 60 ml/min/1.73 m² and whose proteinuria was more than 1.0 g/day.

Recurrence of immunoglobulin A nephropathy after kidney transplantation: a narrative review of the incidence, risk factors, pathophysiology and management of immunosuppressive therapy

Glomerulonephritis (GN) is the underlying cause of end-stage renal failure in 30–50% of kidney transplant recipients. It represents the primary cause of end-stage renal disease for 25% of the dialysis population and 45% of the transplant population. For patients with GN requiring renal replacement therapy, kidney transplantation is associated with superior outcomes compared with dialysis. Recurrent GN was previously considered to be a minor contributor to graft loss, but with the prolongation of graft survival, the effect of recurrent disease on graft outcome assumes increasing importance. Thus the extent of recurrence of original kidney disease after kidney transplantation has been underestimated for several reasons. This review aims to provide updated knowledge on one particular recurrent renal disease after kidney transplantation, immunoglobulin A nephropathy (IgAN). IgAN is one of the most common GNs worldwide. The pathogenesis of IgAN is complex and remains incompletely understood. Evidence to date is most supportive of a several hit hypothesis. Biopsy is mandatory not only to diagnose the disease in the native kidney, but also to identify and characterize graft recurrence of IgAN in the kidney graft. The optimal therapy for IgAN recurrence in the renal graft is unknown. Supportive therapy aiming to reduce proteinuria and control hypertension is the mainstream, with corticosteroids and immunosuppressive treatment tailored for certain subgroups of patients experiencing a rapidly progressive course of the disease with active lesions on renal biopsy and considering safety issues related to infectious complications.

Improving treatment decisions using personalized risk assessment from the International IgA Nephropathy Prediction Tool

Immunosuppression in IgA nephropathy (IgAN) should be reserved for patients at high-risk of disease progression, which KDIGO guidelines determine based solely on proteinuria 1g or more/day. To investigate if treatment decisions can be more accurately accomplished using individualized risk from the International IgAN Prediction Tool, we simulated allocation of a hypothetical immunosuppression therapy in an international cohort of adults with IgAN. Two decision rules for treatment were applied based on proteinuria of 1g or more/day or predicted risk from the Prediction Tool above a threshold probability. An appropriate decision was defined as immunosuppression allocated to patients experiencing the primary outcome (50% decline in eGFR or ESKD) and withheld otherwise. The net benefit and net reduction in treatment are the proportion of patients appropriately allocated to receive or withhold immunosuppression, adjusted for the harm from inappropriate decisions, calculated for all threshold probabilities from 0-100%. Of 3299 patients followed for 5.1 years, 522 (15.8%) experienced the primary outcome. Treatment allocation based solely on proteinuria of 1g or more/day had a negative net benefit (was harmful) because immunosuppression was increasingly allocated to patients without progressive disease. Compared to using proteinuria, treatment allocation using the Prediction Tool had a larger net benefit up to 23.4% (95% confidence interval 21.5-25.2%) and a larger net reduction in treatment up to 35.1% (32.3-37.8%). Thus, allocation of immunosuppression to high-risk patients with IgAN can be substantially improved using the Prediction Tool compared to using proteinuria.

After ten years of follow-up, no difference between supportive care plus immunosuppression and supportive care alone in IgA nephropathy

The randomized, controlled STOP-IgAN trial in patients with IgA nephropathy (IgAN) and substantial proteinuria showed no benefit of immunosuppression added on top of supportive care on renal function over three years. As a follow-up we evaluated renal outcomes in patients over a follow-up of up to ten years in terms of serum creatinine, proteinuria, end-stage kidney disease (ESKD), and death. The adapted primary endpoint was the time to first occurrence of a composite of death, ESKD, or a decline of over 40% in the estimated glomerular filtration rate (eGFR) compared to baseline at randomization into STOP-IgAN. Data were analyzed by Cox-regression models. Follow-up data were available for 149 participants, representing 92% of the patients originally randomized. Median follow-up was 7.4 years (inter quartile range 5.7 to 8.3 years). The primary endpoint was reached in 36 of 72 patients randomized to supportive care and 35 of 77 patients randomized to additional immunosuppression (hazard ratio 1.20; 95% confidence interval 0.75 to 1.92). ESKD occurred in 17 of the patients with supportive care and in 20 of the patients with additional immunosuppression. Additionally, the rates of eGFR loss over 40% and annual eGFR loss did not differ between groups. Two patients died with supportive care and three with additional immunosuppression. Thus, within the limitations of a retrospective study, over a follow-up of up to ten years, and using an adapted primary endpoint, we failed to detect differences in key clinical outcomes in IgAN patients randomized to receive added immunosuppression on top of supportive care versus supportive care alone.

Clinical and Pathophysiological Insights Into Immunological Mediated Glomerular Diseases in Childhood

The kidney is often the target of immune system dysregulation in the context of primary or systemic disease. In particular, the glomerulus represents the anatomical entity most frequently involved, generally as the expression of inflammatory cell invasion or circulant or in situ immune-complex deposition. Glomerulonephritis is the most common clinical and pathological manifestation of this involvement. There are no universally accepted classifications for glomerulonephritis. However, recent advances in our understanding of the pathophysiological mechanisms suggest the assessment of immunological features, biomarkers, and genetic analysis. At the same time, more accurate and targeted therapies have been developed. Data on pediatric glomerulonephritis are scarce and often derived from adult studies. In this review, we update the current understanding of the etiologic events and genetic factors involved in the pathogenesis of pediatric immunologically mediated primitive forms of glomerulonephritis, together with the clinical spectrum and prognosis. Possible new therapeutic targets are also briefly discussed.

The efficacy and safety of immunosuppressive therapies in the treatment of IgA nephropathy: A network meta-analysis

Immunoglobulin A nephropathy (IgAN) is a common autoimmune glomerulonephritis that can result in end-stage renal disease (ESRD). Whether immunosuppressants are superior or equivalent to supportive care is still controversial. A network meta-analysis was conducted to compare the efficacy and safety of immunosuppressive treatment for IgAN. Medline, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and EMBASE were searched on December 30, 2018. We used a random-effects model with a Bayesian approach to appraise both renal outcomes and serious adverse effects. Relative risks (RRs) with 95% confidence intervals (CIs) were calculated to present the relative effects. The ranking probabilities were calculated by the surface under the cumulative ranking curve (SUCRA). In total, 24 RCTs comprising 6 interventions were analyzed. Steroids significantly delayed the progression of renal deterioration with acceptable serious adverse effects, compared with supportive care (RR = 0.28, 95% CI = 0.13–0.51, SUCRA = 48.7%). AZA combined with steroids might be an alternative immunosuppressive therapy. Tacrolimus might decrease the proteinuria level (RR = 3.1, 95% CI = 1.2–9.4, SUCRA = 66.5%) but cannot improve renal function, and the side effects of tacrolimus should not be neglected. MMF and CYC showed no superiority in the treatment of IgAN. In summary, steroids might be recommended as the first-line immunosuppressive therapy for IgAN.

Immunosuppressive agents for treating IgA nephropathy

BACKGROUND

IgA nephropathy is the most common glomerulonephritis world-wide. IgA nephropathy causes end-stage kidney disease (ESKD) in 15% to 20% of affected patients within 10 years and in 30% to 40% of patients within 20 years from the onset of disease. This is an update of a Cochrane review first published in 2003 and updated in 2015.

OBJECTIVES

To determine the benefits and harms of immunosuppression strategies for the treatment of IgA nephropathy.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 9 September 2019 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

We included randomised controlled trials (RCTs) and quasi-RCTs of treatment for IgA nephropathy in adults and children and that compared immunosuppressive agents with placebo, no treatment, or other immunosuppressive or non-immunosuppressive agents.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study risk of bias and extracted data. Estimates of treatment effect were summarised using random effects meta-analysis. Treatment effects were expressed as relative risk (RR) and 95% confidence intervals (95% CI) for dichotomous outcomes and mean difference (MD) and 95% CI for continuous outcomes. Risks of bias were assessed using the Cochrane tool. Evidence certainty was evaluated using GRADE methodology.

MAIN RESULTS

Fifty-eight studies involving 3933 randomised participants were included. Six studies involving children were eligible. Disease characteristics (kidney function and level of proteinuria) were heterogeneous across studies. Studies evaluating steroid therapy generally included patients with protein excretion of 1 g/day or more. Risk of bias within the included studies was generally high or unclear for many of the assessed methodological domains. In patients with IgA nephropathy and proteinuria > 1 g/day, steroid therapy given for generally two to four months with a tapering course probably prevents the progression to ESKD compared to placebo or standard care (8 studies; 741 participants: RR 0.39, 95% CI 0.23 to 0.65; moderate certainty evidence). Steroid therapy may induce complete remission (4 studies, 305 participants: RR 1.76, 95% CI 1.03 to 3.01; low certainty evidence), prevent doubling of serum creatinine (SCr) (7 studies, 404 participants: RR 0.43, 95% CI 0.29 to 0.65; low certainty evidence), and may lower urinary protein excretion (10 studies, 705 participants: MD -0.58 g/24 h, 95% CI -0.84 to -0.33;low certainty evidence). Steroid therapy had uncertain effects on glomerular filtration rate (GFR), death, infection and malignancy. The risk of adverse events with steroid therapy was uncertain due to heterogeneity in the type of steroid treatment used and the rarity of events. Cytotoxic agents (azathioprine (AZA) or cyclophosphamide (CPA) alone or with concomitant steroid therapy had uncertain effects on ESKD (7 studies, 463 participants: RR 0.63, 95% CI 0.33 to 1.20; low certainty evidence), complete remission (5 studies; 381 participants: RR 1.47, 95% CI 0.94 to 2.30; very low certainty evidence), GFR (any measure), and protein excretion. Doubling of serum creatinine was not reported. Mycophenolate mofetil (MMF) had uncertain effects on the progression to ESKD, complete remission, doubling of SCr, GFR, protein excretion, infection, and malignancy. Death was not reported. Calcineurin inhibitors compared with placebo or standard care had uncertain effects on complete remission, SCr, GFR, protein excretion, infection, and malignancy. ESKD and death were not reported. Mizoribine administered with renin-angiotensin system inhibitor treatment had uncertain effects on progression to ESKD, complete remission, GFR, protein excretion, infection, and malignancy. Death and SCr were not reported. Leflunomide followed by a tapering course with oral prednisone compared to prednisone had uncertain effects on the progression to ESKD, complete remission, doubling of SCr, GFR, protein excretion, and infection. Death and malignancy were not reported. Effects of other immunosuppressive regimens (including steroid plus non-immunosuppressive agents or mTOR inhibitors) were inconclusive primarily due to insufficient data from the individual studies in low or very low certainty evidence. The effects of treatments on death, malignancy, reduction in GFR at least of 25% and adverse events were very uncertain. Subgroup analyses to determine the impact of specific patient characteristics such as ethnicity or disease severity on treatment effectiveness were not possible.

AUTHORS' CONCLUSIONS

In moderate certainty evidence, corticosteroid therapy probably prevents decline in GFR or doubling of SCr in adults and children with IgA nephropathy and proteinuria. Evidence for treatment effects of immunosuppressive agents on death, infection, and malignancy is generally sparse or low-quality. Steroid therapy has uncertain adverse effects due to a paucity of studies. Available studies are few, small, have high risk of bias and generally do not systematically identify treatment-related harms. Subgroup analyses to identify specific patient characteristics that might predict better response to therapy were not possible due to a lack of studies. There is no evidence that other immunosuppressive agents including CPA, AZA, or MMF improve clinical outcomes in IgA nephropathy.

Has The Time Arrived to Refine The Indications of Immunosuppressive Therapy and Prognosis in IgA Nephropathy?

Immunoglobulin A nephropathy (IgAN) is the most frequent glomerular disease worldwide and a leading cause of end-stage renal disease. Particularly challenging to the clinician is the early identification of patients at high risk of progression, an estimation of the decline in renal function, and the selection of only those that would benefit from additional immunosuppressive therapies. Nevertheless, the pathway to a better prognostication and to the development of targeted therapies in IgAN has been paved by recent understanding of the genetic and molecular basis of this disease. Merging the data from the Oxford Classification validation studies and prospective treatment studies has suggested that a disease-stratifying algorithm would be appropriate for disease management, although it awaits validation in a prospective setting. The emergence of potential noninvasive biomarkers may assist traditional markers (proteinuria, hematuria) in monitoring disease activity and treatment response. The recent landmark trials of IgAN treatment (STOP-IgAN and TESTING trials) have suggested that the risks associated with immunosuppressive therapy outweigh the benefits, which may shift the treatment paradigm of this disease. While awaiting the approval of the first therapies for IgAN, more targeted and less toxic immunotherapies are warranted. Accordingly, the targeting of complement activation, the modulation of mucosal immunity, the antagonism of B-cell activating factors, and proteasomal inhibition are currently being evaluated in pilot studies for IgAN treatment.

[Pathophysiology and treatment of IgA nephropathy]

The IgA nephropathy is the most frequent form of glomerulonephritis worldwide. In approximately 30% of patients a reduction in the glomerular filtration rate of approximately 50% is observed within 10 years. Patients with IgA nephropathy form IgG autoantibodies against galactose-deficient IgA1 antibodies. This results in deposition of these antibodies in the mesangium and activation of complement with mesangial hypercellularity, endocapillary hypercellularity, segmental glomerulosclerosis and atrophying interstitial fibrosis. The basic treatment for patients with IgA nephropathy consists of removing risk factors, in particular hypertension, with blockade of the renin-angiotensin-aldosterone system. Immunosuppressives were also investigated in various studies but a clear advantage was not observed.