A pre-specified analysis of the DAPA-CKD trial demonstrates the effects of dapagliflozin on major adverse kidney events in patients with IgA nephropathy

Immune cells mediate the effect of plasma lipidomes on IgA nephropathy: a Mendelian randomization study

BACKGROUND

IgA nephropathy (IgAN) is a leading cause of chronic kidney disease, often associated with dyslipidemia and immune dysfunction. This study employs Mendelian randomization (MR) to investigate the causal relationship between plasma lipidomes and IgAN, with a focus on the potential mediating role of immune cells.

METHODS

We analyzed the 179 genetically predicted plasma lipidomes and the IgAN gene using two-sample Mendelian randomization (TSMR) and multivariable MR based on summary-level data from a genome-wide association study, and the results were validated by liquid chromatography-mass spectrometry. Furthermore, we quantified the proportional effect of immune cell-mediated lipidomes on IgAN using TSMR.

RESULTS

This study identified significant causal relationships of 3 lipidomes on IgAN risk by examining 179 lipidome traits as exposures. To investigate whether the impact of the 3 lipid groups on IgAN is specific, we performed TSMR analyses using 3 lipidomes as exposure factors and 4 nephritides as outcomes. Specifically, only phosphatidylinositol (18:1_20:4) was found to have a significant negative relationship with IgAN incidence (IVW method, p = 0.01, OR = 0.71, 95% CI = 0.55 - 0.92). Our further analysis focused on 8 immune cells associated with IgAN. We identified 2 immune cell phenotypes that may contribute to phosphatidylinositol (18:1_20:4)-mediated IgAN by careful screening.

CONCLUSIONS

Our findings provide robust genetic evidence supporting a causal link between plasma lipidomes and IgAN, with immune cells acting as potential mediators. Phosphatidylinositol (18:1_20:4) emerges as a promising biomarker for IgAN risk stratification, early detection, and therapeutic intervention. Modulating its plasma levels may offer novel avenues for IgAN management.

Treatment of immunoglobulin A nephropathy: Current perspective and future prospects

Immunoglobulin (Ig) A nephropathy is the most common type of primary glomerulonephritis globally. It typically manifests with microscopic hematuria and a spectrum of proteinuria, although rapidly progressive glomerulonephritis may occur in rare instances. Deposition of IgA in the mesangium seems to be the underlying disease mechanism. Despite current treatment, IgA nephropathy may progress into end-stage renal disease, indicating the necessity for the development of new therapeutic agents. Lifestyle modifications and anti-proteinuric treatment are recommended, and steroids have shown to be beneficial to high risk groups. Nevertheless, other conventional immunosuppressive agents, such as cyclophosphamide and mycophenolate mofetil, may be considered, despite the lack of sufficient evidence to support their efficacy. A considerable proportion of cases remain unresponsive to these treatments, underscoring the need for novel therapeutic approaches. There are several promising immunosuppressive drugs, such as B-cell lineage depleting agents or complement system inhibitors, that are currently undergoing clinical trials. These therapies may be considered for use in selected cases.

SGLT2 inhibitors use in kidney disease: what did we learn?

Chronic kidney disease (CKD) increases the risk for cardiovascular morbidity and mortality and it's prevalence continues to rise throughout the world. Newer, more efficacious therapies, slow progression of CKD, decrease long-term sequela like end-stage kidney disease (ESKD) and cardiovascular events, improving survival. Postmarketing cardiovascular outcome trials (CVOT) have demonstrated improved cardiovascular outcomes with the use of sodium-glucose cotransporter-2 inhibitors (SGLT2i) like canagliflozin, dapagliflozin, empagliflozin, ertugliflozin, and sotagliflozin in patients with type 2 diabetes mellitus (T2DM), Similarly, secondary analysis of CVOT and renal outcome trials with the use of SGLT2i in patients without T2DM showed improved renal function and albuminuria. In these studies, nondiabetic CKD was defined as an estimated glomerular filtration rate (eGFR) of 20-75 mL/min/1.73 m2 with albuminuria ranging from 200 to 5,000 mg/g in the absence of diabetes. As a class effect, in addition to modulation of hemodynamic and metabolic activities, SGLT2i exert renal protection by suppressing inflammation and fibrosis. We conducted an extensive search in the PubMed database for original papers published from 2009 through 2024 using keywords such as nondiabetic kidney disease, diabetic kidney disease, SGLT2i, and kidney outcomes. Based on our research of published literature, we present a review and propose, consideration of SGLT2i in nondiabetic kidney disease for long-term cardiovascular and renal benefit (Dharia A, Khan A, Sridhar VS, Cherney DZI. Annu Rev Med 74: 369-384, 2023). We will highlight relevant translational studies to propose a possible cell-based mechanism for cardiovascular benefits noted secondary to use of SGLT2i.

SGLT2 Inhibitors in Glomerulonephritis: Beyond Nephroprotection?

Sodium-glucose cotransporter 2 (SGLT2) inhibitors, initially developed for glycaemic control in type 2 diabetes, have demonstrated substantial renal and cardiovascular protective effects across various chronic kidney diseases (CKD), including glomerulonephritis. Beyond their established haemodynamic and metabolic benefits, recent evidence points to additional mechanisms of action potentially relevant to immune-mediated kidney diseases, such as the modulation of inflammation, immunometabolism, and oxidative stress. Randomised clinical trials (DAPA-CKD and EMPA-KIDNEY) and real-world observational studies consistently show that SGLT2 inhibitors reduce proteinuria and slow estimated glomerular filtration rate (eGFR) decline in patients with glomerulonephritis, including IgA nephropathy and focal segmental glomerulosclerosis. These benefits may extend to patients with stable immunosuppression. Further data are needed in this subgroup. Importantly, SGLT2 inhibitors display a favourable safety profile, even among those with immunosuppressed status. Again, further evidence is awaited in this respect. Despite these promising findings, unanswered questions remain regarding their efficacy in nephrotic syndrome, early-stage disease, and in comparison or combination with other supportive therapies. Overall, the evolving evidence supports the inclusion of SGLT2 inhibitors as a key component of supportive therapy in glomerulonephritis, with potential benefits extending beyond proteinuria reduction.

Drug Development in Pediatric Chronic Kidney Disease: A Review of Promising Treatments, Old Challenges, and New Strategies

Youth under the age of 18 years represent a distinct subset of the population living with chronic kidney disease (CKD). The etiology of CKD differs greatly between children and adults, and young people with CKD face an extended lifetime living with their disease. Few rigorous randomized controlled trials in CKD have included people under the age of 18 years. As such, the recent success of CKD trials with sodium glucose co-transporter 2 inhibitors, mineralocorticoid antagonists, dual endothelin agonists, and hypoxia-induced factor prolyl hydroxylase inhibitors have largely not extended to children and adolescents. There are many reasons to believe these medications could prove as transformative in youth as they have in older adults, but trial data are missing. Innovative strategies are required to ensure that trials of recent, and future, agents in youth with CKD are successful.

Updates in chronic kidney disease management: A systematic review

Chronic kidney disease (CKD) is a significant global health challenge that impacts both patients and the health care system. This systematic review aims to evaluate the efficacy and safety of emerging therapeutic strategies for CKD management, including sodium-glucose cotransporter 2 inhibitors (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP-1RA), finerenone, sacubitril/valsartan, and potassium binders. We conducted searches in databases including PubMed, Scopus, CINAHL Complete, and Web of Science Core Collection to identify experimental and observational studies pertaining to each of these agents. Included studies were those that enrolled adult patients with CKD who evaluated SGLT2i, GLP-1RA, finerenone, sacubitril/valsartan, and potassium binders compared to other medications or placebo and evaluated renal-related outcomes as a primary or secondary outcome. Methodological quality and risk of bias were assessed using the Cochrane Risk of Bias (version 2) tool for experimental studies and ROBINS-I for observational studies. After screening 2135 unique studies, 138 studies were eligible for this review. These studies describe a substantial and growing body of evidence focused on improving the management of CKD beyond renin-angiotensin system inhibitors (RASi), such as angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARBs). Currently, SGLT2i have demonstrated consistent benefits with large effect sizes in preventing the progression of CKD, solidifying this class as a first-line treatment along with RASi. Subsequent consideration for GLP-1RA, finerenone, and sacubitril/valsartan should be dependent on patient-specific comorbidities, while potassium binders may allow for longer use of RASi.

Tailored management strategies for IgA nephropathy based on clinical presentations

The treatment landscape for immunoglobulin A nephropathy is rapidly evolving with the introduction of novel therapies targeting diverse disease pathways. Some have already been approved in different countries, while others are under investigation in randomized controlled trials (RCTs) with encouraging results. However, almost all performed RCTs have included only patients with refractory non-nephrotic proteinuria and preserved renal function. Other clinical presentations (rapidly progressive forms, malignant hypertension, thrombotic microangiopathy, nephrotic syndrome) have received less attention and are systematically excluded from RCTs. In contrast, certain aspects, such as the impact of haematuria or management in special populations (e.g. pregnant patients or transplant recipients), remain underexplored. This review proposes therapeutic algorithms to guide treatment decisions in different clinical scenarios while highlighting gaps in current research.

Late Allograft Loss and Contemporary Cardiorenal Metabolic Therapies

Late kidney allograft loss occurs through one of two mechanisms: ( 1 ) deterioration of kidney function leading to retransplantation or dialysis (death-censored graft loss) and ( 2 ) premature death with a normally functioning transplant (death with graft function)-each accounting for approximately 50% of late kidney graft losses. Late death-censored graft loss typically results from a combination of immune and nonimmune events leading to common nonspecific end points ( e.g ., tubular atrophy, interstitial fibrosis, and glomerulosclerosis). Conversely, leading causes of death with graft function typically include cardiovascular events, malignancy, and infection. With an improved understanding of the multiple mechanism by which late graft dysfunction develops, there is an opportunity to identify patients at greatest risk and institute novel strategies to quell the process. Newer cardiometabolic agents with proven benefit in the general population have not been well-studied in kidney transplant recipients. However, in addition to their potential benefits in reducing cardiovascular, infectious, and malignancy end points (thus minimizing death with graft function risk), many novel agents may have additional anti-inflammatory and/or antifibrotic benefit (minimizing death-censored graft loss risk) in the kidney transplant population. In this review, we summarize existing literature regarding major causes of death-censored graft loss and death with graft function and discuss the potential roles of new cardiorenal metabolic agents including sodium-glucose cotransport 2 inhibitors, nonsteroidal mineralocorticoid receptor antagonists, glucagon-like peptide 1 receptor agonists, and dual endothelin and angiotensin receptor antagonists in the kidney transplant population, including potential mechanisms to improve death with graft function and death-censored graft loss outcomes.

Treatment of patients with IgA nephropathy: a call for a new paradigm

IgA nephropathy (IgAN), the world's most common primary glomerular disease, carries a significant lifetime risk for kidney failure as well as an enormous socioeconomic burden. In the past, studies in patients with IgAN largely focused on optimizing so-called supportive care, that is, blockade of the renin-angiotensin system, blood pressure control, and lifestyle modifications. The effectiveness of immunosuppressive measures, particularly high-dose corticosteroid therapy, has been reported variably, but there is considerable evidence for an increase in serious adverse effects with such therapies. This disappointing situation has changed dramatically with a better understanding of the pathogenesis of IgAN, and with regulatory agencies accepting changes in proteinuria and the estimated glomerular filtration rate loss or slope over 2 to 3 years as surrogate outcome markers. A multitude of new therapies are now being evaluated in IgAN, and several drugs, such as sodium-glucose transporter-2 inhibitors, sparsentan (a dual endothelin-1 and angiotensin II receptor blocker), nefecon (a targeted release formulation of budesonide), and iptacopan (a complement factor B inhibitor), have been approved, with more to come in the next few years. In this review, we propose a new treatment paradigm that combines therapies with different mechanisms of action to target the immune components and the chronic kidney disease components of IgAN in parallel to preserve long-term kidney survival.

Population-Level Risk Factors for Kidney Outcomes in IgA Nephropathy: The CURE-CKD Registry

Rationale & Objective

Although IgA nephropathy (IgAN) therapies are advancing quickly, therapeutic interventions are hampered by a lack of kidney disease identification and risk assessment. The study aim was to use population-level data from health systems to identify IgAN and assess risks.

Study Design

A longitudinal and real-world cohort study.

Setting & Participants

Electronic health record data for patients ≥18 years old with IgAN at Providence and University of California Los Angeles health systems during 2016-2022.

Predictors

Health insurance and care utilization along with age, gender, race, ethnicity, estimated glomerular filtration rate (eGFR), urine albumin/creatinine ratio (UACR) or urine protein/creatinine ratio (UPCR), diabetes, hypertension, and medications.

Outcomes

Time to first major adverse kidney event (MAKE): ≥40% eGFR decline; eGFR <15 mL/min/1.73 m2; administrative codes for kidney failure, dialysis, or transplant; and death.

Analytical Approach

Kaplan-Meier survival curves and Cox proportional hazards models.

Results

Patients with IgAN (n = 2,571) were 50% (n = 1,277) women and 58 ± 18 (mean ± SD) years old. At baseline, eGFR was 78 ± 27 mL/min/1.73 m2 (chronic kidney disease epidemiologic 2021 equation); median UACR and UPCR were 166 (interquartile range 25-795) mg/g and 0.7 (0.2-1.8) g/g, respectively, among those with baseline measurements (n = 669). MAKE occurred in 22% of the cohort by 3 years. In Cox proportional hazards models, MAKE was predicted by noncommercial (Medicare or Medicaid) health insurance, hospitalization, more frequent outpatient encounters, lower eGFR, and a higher UACR or UPCR.

Limitations

Missingness, miscoding, and retrospective data.

Conclusions

Substantial loss of kidney function, kidney failure, and death were common events over a short period of time in patients with IgAN. Within health system populations, noncommercial health insurance and greater care utilization augmented risk prediction and could help to identify those who may benefit from closer monitoring and implementation of therapeutic interventions.

Efficacy and Safety of Ravulizumab in IgA Nephropathy: A Phase 2 Randomized Double-Blind Placebo-Controlled Trial

Key Points

This phase 2, double-blind, randomized controlled trial evaluated the complement C5 inhibitor, ravulizumab, in adults with IgA nephropathy. A 30.1% (90% confidence interval, 13.7% to 43.5%) relative reduction in proteinuria for ravulizumab versus placebo was observed at approximately 6 months. Treatment with ravulizumab was well tolerated.

Background

The complement system plays a central role in the pathogenesis of IgA nephropathy. We present findings from a phase 2 trial of ravulizumab, a complement C5 inhibitor.

Methods

The Study of Ravulizumab in Proliferative Lupus Nephritis or IgA Nephropathy (NCT04564339 ) was a randomized, double-blind, placebo-controlled trial of ravulizumab in addition to standard of care. Adults with IgA nephropathy, proteinuria ≥1 g/d, and eGFR ≥30 ml/min per 1.73 m2, and on stable renin-angiotensin blockade were randomized 2:1 to ravulizumab (intravenous every 8 weeks) or placebo for 26 weeks. From week 26–50, all participants received open-label ravulizumab. The primary end point was percentage change in proteinuria from baseline to week 26. Secondary end points included change in proteinuria at week 50 and eGFR. Safety, pharmacokinetics, and pharmacodynamics were evaluated.

Results

Forty-three patients were randomized to ravulizumab and 23 to placebo. At week 26, a statistically significant reduction in proteinuria was observed with ravulizumab versus placebo: −41.9% (95% confidence interval [CI], −50.2% to −32.0%) change in urine protein with ravulizumab and −16.8% (95% CI, −31.8% to 1.6%) change with placebo (30.1% treatment effect; P = 0.005). At week 50, there was a −44.8% (95% CI, −55.1% to −32.1%) change from baseline in urine protein with ravulizumab, and in patients who crossed over from placebo to ravulizumab at week 26, the change from baseline (week 0) to week 50 was −45.1% (−58.0% to −28.4%). The least squares mean change in eGFR from baseline to week 26 with ravulizumab was 0.2 (95% CI, −2.3 to 2.7) ml/min per 1.73 m2 and with placebo was −4.5 (−7.9 to −1.1) ml/min per 1.73 m2. From baseline to week 50, the least squares mean change in eGFR with ravulizumab was −3.9 (95% CI, −6.4 to−1.3) ml/min per 1.73 m2, and in patients who crossed over from placebo to ravulizumab at week 26, it was −6.3 (−9.7 to −2.9) ml/min per 1.73 m2. Ravulizumab was well tolerated, with an adverse event profile similar to that for placebo.

Conclusions

An early, sustained, and clinically meaningful reduction in proteinuria and trend toward stabilization of eGFR were observed with ravulizumab versus placebo. A phase 3 trial (NCT06291376 ) is enrolling.

Clinical Trial registry name and registration number:

Study of Ravulizumab in Proliferative Lupus Nephritis or IgA Nephropathy, NCT04564339 .

Podcast

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2024_10_26_KTS_October2024.mp3

The Selective Endothelin Receptor Antagonist SC0062 in IgA Nephropathy: A Randomized Double-Blind Placebo-Controlled Clinical Trial

Key Points

Patients with IgA nephropathy and significant proteinuria are at high risk of progressive kidney function loss and kidney failure. We report the results of a clinical trial assessing the selective endothelin receptor antagonist SC0062 for the treatment of IgA nephropathy. SC0062 led to clinically meaningful improvements in proteinuria and did not increase risk of peripheral edema at higher doses.

Background

Endothelin receptor type A activation contributes to kidney injury in patients with IgA nephropathy. SC0062 is a novel selective endothelin receptor type A antagonist. We report the results of a phase 2 dose-finding trial to characterize the efficacy and safety of SC0062 in patients with IgA nephropathy.

Methods

We conducted a randomized, placebo-controlled, double-blind, clinical trial in adults with biopsy-proven IgA nephropathy and eGFR ≥30 ml/min per 1.73 m2 with urine protein-creatinine ratio (UPCR) ≥0.75 g/g or proteinuria ≥1 g/24 hour despite using maximum tolerated doses of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Patients were randomized 1:1:1:1 to 24-week treatment with SC0062 5, 10, and 20 mg or matching placebo once daily. The primary efficacy outcome was percent change from baseline in UPCR in 24-hour urine samples after 12 weeks of treatment. Secondary end points included changes in eGFR. Safety outcomes including treatment-emergent adverse events and serious adverse events were recorded.

Results

Overall, 131 patients (mean age 42 years [SD 11]; mean eGFR 72 ml/min per 1.73 m2 [SD 24] and median 24-hour UPCR 1.2 g/g [25th–75th percentile, 0.9–1.5 g/g]) were randomized to placebo (n =34) or SC0062 5 mg (n =33), 10 mg (n =32), or 20 mg (n =32). All SC0062 doses reduced UPCR versus placebo throughout treatment. At week 12, placebo-corrected geometric mean changes (95% confidence interval) from baseline in UPCR with SC0062 5, 10, and 20 mg were−27.6% (−43.0 to −8.2), −20.5% (−37.4 to 1.0), and −38.1% (−51.4 to −21.0), respectively, and at week 24 they were−22.4% (−42.2 to 4.3), −30.9% (−48.6 to −7.0), and −51.6% (−64.2 to −34.6), respectively. No differences in eGFR were observed among treatment groups. The proportion of participants with treatment-emergent adverse events or serious adverse events was balanced among treatment groups. Peripheral edema was reported by two (6%), one (3%), one (3%) participants in the 5, 10, and 20 mg SC0062-treated groups, respectively, compared with five (15%) in the placebo group.

Conclusions

In patients with IgA nephropathy, SC0062 reduced proteinuria and did not increase risk of peripheral edema.

Clinical Trial registry name and registration number:

A Study to Evaluate the Efficacy and Safety of SC0062 in the Treatment of CKD, NCT05687890 .

Podcast

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2024_10_26_KTS_October2024.mp3

Osmotic nephropathy triggered by sodium-glucose cotransporter 2 inhibitors in a patient with IgA nephropathy

A woman with biopsy-confirmed IgA nephropathy (IgAN) presented with persistent non-nephrotic range proteinuria and stage 3b chronic kidney disease (CKD). Her treatment regimen included the initiation of a sodium-glucose cotransporter 2 inhibitor (SGLT2i), dapagliflozin, starting at 5 mg daily and later titrated to 10 mg daily after several months. Following the dose increase, she developed significant acute-on-chronic kidney injury. Despite discontinuing the SGLT2i, her renal function did not recover. A subsequent kidney biopsy revealed findings consistent with osmotic tubulopathy with worsening IgAN. This case highlights a rare but important adverse effect of SGLT2i, particularly in patients with pre-existing CKD. While initial expert guidance advised against routine renal function monitoring to avoid premature discontinuation due to the expected transient rise in creatinine, evolving clinical experience suggests that individualised monitoring may be necessary in high-risk patients. Future guidelines will need to clarify how to balance these considerations to optimise patient outcomes.

Risk Stratification in Immunoglobulin A Nephropathy Using Network Biomarkers: Development and Validation Study

BACKGROUND

Traditional risk models for immunoglobulin A nephropathy (IgAN), which primarily rely on renal indicators, lack comprehensive assessment and therapeutic guidance, necessitating more refined and integrative approaches.

OBJECTIVE

This study integrated network biomarkers with unsupervised learning clustering (k-means clustering based on network biomarkers [KMN]) to refine risk stratification in IgAN and explore its clinical value.

METHODS

Involving a multicenter prospective cohort, we analyzed 1460 patients and validated the approach externally with 200 additional patients. Deeper metabolic and microbiomic insights were gained from 2 distinct cohorts: 63 patients underwent ultraperformance liquid chromatography-mass spectrometry, while another 45 underwent fecal 16S RNA sequencing. Our approach used hierarchical clustering and k-means methods, using 3 sets of indicators: demographic and renal indicators, renal and extrarenal indicators, and network biomarkers derived from all indicators.

RESULTS

Among 6 clustering methods tested, the KMN scheme was the most effective, accurately reflecting patient severity and prognosis with a prognostic accuracy area under the curve (AUC) of 0.77, achieved solely through cluster grouping without additional indicators. The KMN stratification significantly outperformed the existing International IgA Nephropathy Prediction Tool (AUC of 0.72) and renal function-renal histology grading schemes (AUC of 0.69). Clinically, this stratification facilitated personalized treatment, recommending angiotensin-converting enzyme inhibitors or angiotensin receptor blockers for lower-risk groups and considering immunosuppressive therapy for higher-risk groups. Preliminary findings also indicated a correlation between IgAN progression and alterations in serum metabolites and gut microbiota, although further research is needed to establish causality.

CONCLUSIONS

The effectiveness and applicability of the KMN scheme indicate its substantial potential for clinical application in IgAN management.

Recent Developments in Pediatric Nephrology

Urinary tract infection (UTI) is a common bacterial infection in children that affects 1 [...].

Sodium-glucose co-transporter inhibitors for APOL1 kidney disease: A call for studies

Renal risk variants in the apolipoprotein L1 (APOL1) gene confer protection against trypanosomiasis, but these risk variants (G1 and G2 variants) also predispose to kidney disease among individuals, especially from Sub-SaharanAfrica. Currently, the mechanisms of how these renal risk variants induce kidney damage are not precisely defined, but lysosomal and mitochondrial dysfunction, altered ion channel activity, altered autophagy, and disordered immunity are suggested. Currently, there is no specific treatment for APOL1 kidney disease (APOL1-KD) although several potential disease-specific therapeutic agents are being evaluated in clinical trials. Non-specific interventions include proteinuria screening, salt restriction, and renin-angiotensin-aldosterone system inhibition but are not sufficient to prevent kidney disease progression in APOL1-KD. Given the lack of specific treatment options, more efforts are necessary to reduce kidney disease progression. Sodium glucose co-transport-2 (SGLT2) inhibitors (SGLT2i) are gaining attention for benefits in proteinuric kidney diseases and exert many beneficial effects which theoretically may be beneficial in the context of APOL1-KD. These beneficial effects include but are not limited to increased natriuresis, decreased proteinuria/albuminuria, and mitochondrial dysfunction. SGLT2i have antioxidant, anti-inflammatory and anti-fibrotic effects. In the current review, we highlight the potential reasons for exploring the use of SGLT2i in APOL1-KD. Future studies are warranted to explore if SGLT2i use can provide protection in APOL1-KD.

Have SGLT-2 inhibitors DELIVERed an EMPhatic win in heart failure and chronic kidney disease?

INTRODUCTION

Major global guidelines currently recommend sodium-glucose co-transporter-2 inhibitors (SGLT-2i) as the first-line agent in people with type 2 diabetes (T2D) who have either established cardiovascular disease (eCVD), heart failure (HF), or chronic kidney disease (CKD), regardless of baseline glycated hemoglobin (HbA1c). Moreover, SGLT-2i are currently included in guideline-directed medical therapy as one of the pillars for people with HF and CKD, regardless of T2D. These recommendations are based on positive cardio-renal outcomes from several randomized controlled trials (RCTs).

AREAS COVERED

Following an extensive search in electronic databases of PubMed, Google Scholar, and clinicaltrials.gov, we critically analyzed the RCTs that assessed cardio-renal outcome trials of SGLT-2i and put a perspective on how SGLT-2i delivered an emphatic win for people with HF and CKD, with or without T2D.

EXPERT OPINION

From thirteen high-quality RCTs, including five cardiovascular outcome trials, five HF outcome trials, three renal outcome trials, and a pooled meta-analysis, it is evident that SGLT-2i has delivered an emphatic win in people with HF and CKD, with or without T2D, with an acceptable safety profile. Ongoing RCTs shall further enlighten whether SGLT-2i will be effective in polycystic kidney disease, lupus nephritis, vasculitis, end-stage CKD with or without hemodialysis, and renal transplant.

SGLT2 Inhibitors: The First Endothelial-Protector for Diabetic Nephropathy

Sodium-glucose co-transporter type 2 inhibitors (SGLT2i) have emerged as a class of agents relevant for managing diabetic nephropathy and cardiopathy. In a previous report, we noticed that these drugs share, with other drugs with "nephroprotective" effects, the ability to reduce the glomerular filtration rate (GFR), thus suggesting the kidney hemodynamic effect as a proxy for optimal drug dosage. We also noticed that all known nephroprotective drugs exert cardioprotective functions, suggesting the possibility of activities not mediated by the kidney. Finally, we observe that nephroprotective drugs can be grouped according to their effects on hemoglobin levels, thus suggesting their mechanism of action. While the primary mechanism of SGLT2i involves glycosuria and natriuria, growing evidence suggests broader therapeutic effects beyond hemodynamic modulation. Specifically, the evidence that SGLT2 can be expressed in several atypical regions under pathological conditions, supports the possibility that its inhibition has several extratubular effects. Evidence supports the hypothesis that SGLT2i influence mitochondrial function in various cell types affected by diabetes, particularly in the context of diabetic nephropathy. Notably, in SGLT2i-treated patients, the extent of albumin-creatinine ratio (ACR) reduction post-treatment may be correlated with mitochondrial staining intensity in glomerular endothelial cells. This implies that the anti-proteinuric effects of SGLT2i could involve direct actions on glomerular endothelial cell. Our investigation into the role of SGLT2 inhibitors (SGLT2i) in endothelial function suggests that the aberrant expression of SGLT2 in endothelial cells in T2DM would lead to intracellular accumulation of glucose; therefore, SGLT2i are the first type of endothelial protective drugs available today, with potential implications for ageing-related kidney disease. The review reveals two major novel findings: SGLT2 inhibitors are the first known class of endothelial-protective drugs, due to their ability to prevent glucose accumulation in endothelial cells where SGLT2 is aberrantly expressed in Type 2 Diabetes. Additionally, the research demonstrates that SGLT2 inhibitors share a GFR-reducing effect with other nephroprotective drugs, suggesting both a mechanism for optimal drug dosing and potential broader applications in ageing-related kidney disease through their effects on mitochondrial function and glomerular endothelial cells.

Machine learning-based unsupervised phenotypic clustering analysis of patients with IgA nephropathy: Distinct therapeutic responses of different groups

BACKGROUND

Immunoglobulin A nephropathy (IgAN) has a heterogeneous clinical presentation. Comparison of different IgAN subgroups may facilitate the application of more targeted therapies. This study was aimed to distinct disease phenotypes in IgAN and to develop prognostic models for renal composite outcomes.

METHODS

Clinical and pathological data were from 2000 patients with biopsy-proven primary IgAN from four centers, including the First Affiliated Hospital of Sun Yat-sen University (SYSU), the Fifth Affiliated Hospital of Sun Yat-sen University, the Huadu District People's Hospital of Guangzhou, and Jieyang Affiliated Hospital of SYSU in China between January 2009 and December 2018 (training cohort: 1203 patients, validation cohort: 797 patients). Components from principal components analysis (PCA) were used to fit a k-means clustering algorithm and identify distinct subgroups. A subgroup-based prediction model was developed to assess prognosis and therapeutic efficacy in each subgroup.

RESULTS

The PCA-k-means clustering algorithm identified four subgroups. Subgroup 1 had significantly better long-term renal survival upon administration of a renin-angiotensin system blocker (adjusted hazard ratio [aHR]: 0.16, 95% confidence interval [CI]: 0.10-0.27, P <0.001). Subgroup 2 had a significant improvement from corticosteroid therapy (aHR: 0.19, 95% CI: 0.06-0.61, P = 0.005). Subgroups 3 and 4 had milder pathological changes and relatively stable kidney function for several years. Subgroup 3 (predominantly males) had a high incidence of metabolic risk factors, necessitating more intensive monitoring; subgroup 4 (predominantly females) had a high incidence of recurrent macroscopic hematuria. These patterns were similar in the validation cohort. A subgroup-based prognosis prediction model demonstrated an area under the curve of 0.856 in the validation dataset.

CONCLUSION

The unsupervised clustering method provided reliable classification of IgAN patients into different subgroups according to clinical features, prognoses, and treatment responsiveness. Our subgroup-based prediction model has significant clinical utility for the assessment of risk and treatment in patients with IgAN.

The road ahead: emerging therapies for primary IgA nephropathy

Primary IgA nephropathy (IgAN) is the most common form of primary glomerulopathy. A slowly progressive disease presenting in the young to middle-aged, most patients with reduced eGFR or proteinuria will progress to end-stage kidney disease (ESKD) in their lifetimes. The pathogenesis involves increased production of galactose-deficient IgA1 (Gd-IgA1) that forms immune complexes that deposit in the glomerulus, eliciting mesangial cell proliferation, inflammation, and complement activation. The backbone of therapy is supportive, including lifestyle modifications, strict blood pressure control, and renin-angiotensin system inhibition targeting proteinuria < 300 mg/day. Sodium-glucose transporter 2 inhibitors are indicated for persisting proteinuria or declining eGFR. Sparsentan is indicated for persisting proteinuria. Immunosuppression should be considered for all patients at risk for progression (persisting proteinuria and/or declining eGFR). To reduce Gd-IgA1 production, targeted-release budesonide is approved. Agents targeting B cell survival factors APRIL or BAFF/APRIL have significantly reduced Gd-IgA1 production and proteinuria in phase 2 trials but await phase 3 data for approval. To reduce inflammation, high-dose steroids are ineffective and toxic in Caucasian patients, although lower-dose regimens may be effective in Chinese patients. Complement inhibition is being actively studied. The factor B inhibitor iptacopan has conditional approval. The terminal pathway inhibitors cemdisiran and ravulizumab show promise in phase 2 studies. Our current approach for those requiring immunosuppression involves combining the reduction of Gd-IgA1 (nefecon) with suppressing the effects of inflammation (iptacopan). The optimal duration of such therapy is uncertain. Clearly, there is more to be learned with many trials underway.

A novel agent targeting APRIL: A new hope for elderly patients of IgA nephropathy

Sibeprenlimab is a humanized IgG2 monoclonal antibody that binds to and neutralizes the activity of APRIL. It should usher in a new era in the treatment of IgAN, especially in elderly patients.

Sodium glucose co-transporter 2 inhibitors (SGLT2i) for pediatric kidney disease: the future is near

The sodium glucose co-transporter 2 (SGLT2) functions in the proximal tubule to reabsorb the bulk of filtered glucose. SGLT2 inhibitors have been developed to promote renal glucose excretion to improve glycemic control in diabetes. Regulatory guidance mandated adequately powered studies to detect increased cardiovascular risk from emerging hypoglycemic medications. This led to recognition of remarkable improvement in cardiovascular and kidney outcomes with SGLT2 inhibition. Moreover, cardiovascular and kidney benefits extend beyond patients with diabetes. The dramatic kidney benefits of SGLT2 inhibitors documented in CKD in adult patients underscores the need for pediatric nephrologists to familiarize themselves with SGLT2 inhibitor therapies. This review explores the currently available body of knowledge regarding the kidney protective effects of SGLT2 inhibitors in adults and mechanisms thought to contribute to improved kidney outcomes. The limited data for SGLT2i treatment in pediatric kidney disease are reviewed and highlight the need for randomized controlled trials of this drug class in pediatric kidney patients as has been done for pediatric diabetes. Dosing patterns for SGLT2 inhibitors from other pediatric settings are reviewed as well as guidance for initiating SGLT2 inhibition in young adults remaining in pediatric nephrology care.

Single-Cell RNA-Sequencing Analysis Provides Insights into IgA Nephropathy

IgA nephropathy (IgAN) is currently the most common primary glomerular disease worldwide, and early diagnosis and intervention contribute significantly to improving outcomes and reducing the incidence of renal failure. The pathogenesis of IgAN remains incompletely understood. In recent years, the rapid development of single-cell RNA-sequencing (scRNA-seq) technology has provided the high-resolution and rich data necessary to elucidate disease characteristics and enabled the analysis of complex interactions between individual cells and cell types. The application of scRNA-seq in IgAN successfully revealed the landscape of immunological features, including peripheral blood B-cell and Th-cell activation, cytotoxic T-cell depletion, and renal infiltrating cell subtypes, as well as the crucial role of mesangial cells and endothelial cells in the early stage of kidney injury, and also revealed the extensive intercellular interactions between renal cells. Here, we discuss the research progress of scRNA-seq technology in IgAN. These scRNA-seq profiles help us to understand the complex molecular mechanisms of IgAN and develop biomarkers and specific therapeutic strategies.

Factors influencing early response of IgA nephropathy following targeted-release budesonide (TRB) treatment: preliminary results from a multicenter study

Background

Formation of galactose-deficient IgA1 (Gd-IgA1) immunoglobulin is the initial step in the immunological cascade leading to IgA nephropathy (IgAN). Targeted-release budesonide (TRB), an evidence-based regimen without major side-effects, has recently been approved for IgAN treatment; herein we present our preliminary real-world data regarding prompt response to TRB.

Methods

Patients with primary IgAN who remained with Uprot >1 g/24 h despite conventional treatment for 6 months were started on TRB, and re-evaluated at 3 (T3) and 6 (T6) months. Reduction of proteinuria by ≥30%, at T3 and T6 was regarded as very early (VER) and early response (ER), respectively. Kidney biopsies were evaluated according to Oxford classification (MEST-C) score.

Results

Thirty-seven IgAN patients, male/female 26/11, mean ± standard deviation age 50.38 ± 14.32 years and mean time since diagnosis 45.65 ± 56.67 months, were included. Seventeen (45.94%) patients demonstrated VER, increasing to 29 (78.3%) as ER (P = .004). Patients who demonstrated VER had a shorter time interval since diagnosis compared with non-VER, 29.41 ± 6.96 vs 65.37 ± 17.64 months (P = .05), and preserved estimated glomerular filtration rate at diagnosis and T0, while time since diagnosis was the main factor associated with ER, 38.36 ± 19.6 vs 78.67 ± 18.64 months, in ER and non-ER respectively (P = .05). Patients with M0, E0, S0 and T0 had no significant changes during T0-T6, while patients with M1, E1, S1 and even T1 had significantly reduced proteinuria (P = .006, P = .0011, P < .0001 and P < .0001, respectively).

Conclusions

Almost half of the patients showed proteinuria reduction after TRB treatment at 3 months, and the proportion increased significantly at 6 months. Patients likely to have a prompt proteinuria reduction were relatively close to diagnosis, retained kidney function and had active lesions in kidney biopsy.

The pathogenesis of IgA nephropathy and implications for treatment

IgA nephropathy (IgAN) is a common form of primary glomerulonephritis and represents an important cause of chronic kidney disease globally, with observational studies indicating that most patients are at risk of developing kidney failure within their lifetime. Several research advances have provided insights into the underlying disease pathogenesis, framed by a multi-hit model whereby an increase in circulating IgA1 that lacks galactose from its hinge region - probably derived from the mucosal immune system - is followed by binding of specific IgG and IgA antibodies, generating immune complexes that deposit within the glomeruli, which triggers inflammation, complement activation and kidney damage. Although treatment options are currently limited, new therapies are rapidly emerging that target different pathways, cells and mediators involved in the disease pathogenesis, including B cell priming in the gut mucosa, the cytokines APRIL and BAFF, plasma cells, complement activation and endothelin pathway activation. As more treatments become available, there is a realistic possibility of transforming the long-term outlook for many individuals with IgAN.

First real-world evidence of sparsentan efficacy in patients with IgA nephropathy treated with SGLT2 inhibitors

Background

Sparsentan, a dual-acting antagonist for both the angiotensin II receptor type 1 and the endothelin receptor type A, has emerged as a promising therapeutic agent for the treatment of IgA nephropathy (IgAN). Following the publication of the PROTECT trial, sparsentan recently received approval for the treatment of IgAN in Europe. However, it remains uncertain whether an additive effect can be observed in the context of existing treatment with sodium-glucose co-transporter 2 (SGLT2) inhibitors, given that the PROTECT study did not investigate this dual therapy approach.

Methods

A total of 23 patients with IgAN were treated with sparsentan via the Managed Access Programme between December 2023 and August 2024. The patients were stable on maximum tolerated doses of renin-angiotensin system (RAS) and SGLT2 inhibitors, with an estimated glomerular filtration rate (eGFR) >30 mL/min/1.73 m² and a urine protein/creatinine ratio (UPCR) >0.75 g/g.

Results

In the 23 patients, median (IQR) baseline eGFR (CKD-EPI) was 42 mL/min/1.73 m2 (32-63) and median baseline UPCR was 1.5 g/g (0.9-1.8). After initiation of sparsentan, UPCR significantly decreased (P < 0.0001) to a median of 0.85 g/g (0.42-1.15) in the 2-week follow-up and further declined (P = 0.001) to a median of 0.60 g/g (0.32-0.82) after 14 weeks, equivalent to a relative reduction in proteinuria up to 62% (45-74). A similar significant reduction was observed for the urine albumin/creatinine ratio. No drug-related serious adverse events were reported.

Conclusions

In this real-world setting, sparsentan shows a significant impact on proteinuria, leading to a relative reduction of 62% in UPCR after 14 weeks and beyond, even in patients already receiving SGLT2 inhibitors.

Comparative Efficacy and Safety of Cardio-Renoprotective Pharmacological Interventions in Chronic Kidney Disease: An Umbrella Review of Network Meta-Analyses and a Multicriteria Decision Analysis

Sodium-glucose co-transporter 2 inhibitors (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP1a), and non-steroidal mineralocorticoid receptor antagonists (ns-MRA) are promising treatments for chronic kidney disease. This umbrella review of network meta-analyses evaluated their effects on cardiovascular outcomes, kidney disease progression, and adverse events, using the TOPSIS method to identify the optimal intervention based on P-scores. A total of 19 network meta-analyses and 44 randomized controlled trials involving 86,150 chronic kidney disease patients were included. Compared to placebo, SGLT2i were associated with reduced risks of cardiovascular events [Hazard ratio (HR): 0.776, 95% confidence intervals (CI): 0.727-0.998], kidney disease progression (HR: 0.679, 95% CI: 0.629-0.733), acute kidney injury (HR: 0.873, 95% CI: 0.773-0.907), and serious adverse events (HR: 0.881, 95% CI: 0.847-0.916). GLP1a and ns-MRA were also associated with significant reductions in cardiovascular and kidney-specific composite outcomes. Indirect evidence showed that SGLT2i demonstrated a lower risk of kidney disease progression compared to GLP1a (HR: 0.826, 95% CI: 0.716-0.952) and ns-MRA (HR: 0.818, 95% CI: 0.673-0.995), representing the best intervention across all endpoints. In conclusion, while SGLT2i, GLP1a, and ns-MRA all reduce cardiovascular and kidney disease risks in chronic kidney disease, SGLT2i appears to provide the most favorable balance of efficacy and safety.

What is new in the pathogenesis and treatment of IgA glomerulonephritis

Recently, new findings have been clarified concerning both pathogenesis and treatment of IgA nephritis. The four hits theory has been confirmed but several genetic wide association studies have allowed finding several genes connected with the pathogenesis of the disease. All these new genes apply to each of the four hits. Additionally, new discoveries concerning the microbiota and its connection with immune system and IgA generation have allowed finding out the role of the mucosa in IgA nephropathy pathogenesis. The IgA treatment is also changed included the future possibilities. The treatment of the chronic kidney disease, associated with the nephropathy, is mandatory, since the beginning of the disease. The classical immunosuppressive agents have poor effect. The corticosteroids remain an important cornerstone in any phase of the disease. More effect is related to the treatment of B cells and plasma cells. In particular, in very recent studies have been documented the efficacy of anti B cell-activating factor and anti A proliferation-inducing ligand agents. Most of these studies are to date in phase II/III. Finally, new agents targeting complement are arising. These agents also are still in randomized trials and act principally in hit 4 where the immunocomplexes in the mesangium activate the different pathways of the complement cascade.

Urinary TYROBP and HCK as genetic biomarkers for non-invasive diagnosis and therapeutic targeting in IgA nephropathy

Background

IgA nephropathy (IgAN) is a leading cause of renal failure, but its pathogenesis remains unclear, complicating diagnosis and treatment. The invasive nature of renal biopsy highlights the need for non-invasive diagnostic biomarkers. Bulk RNA sequencing (RNA-seq) of urine offers a promising approach for identifying molecular changes relevant to IgAN.

Methods

We performed bulk RNA-seq on 53 urine samples from 11 untreated IgAN patients and 11 healthy controls, integrating these data with public renal RNA-seq, microarray, and scRNA-seq datasets. Machine learning was used to identify key differentially expressed genes, with protein expression validated by immunohistochemistry (IHC) and drug-target interactions explored via molecular docking.

Results

Urine RNA-seq analysis revealed differential expression profiles, from which TYROBP and HCK were identified as key biomarkers using machine learning. These biomarkers were validated in both a test cohort and an external validation cohort, demonstrating strong predictive accuracy. scRNA-seq confirmed their cell-specific expression patterns, correlating with renal function metrics such as GFR and serum creatinine. IHC further validated protein expression, and molecular docking suggested potential therapeutic interactions with IgAN treatments.

Conclusion

TYROBP and HCK are promising non-invasive urinary biomarkers for IgAN. Their predictive accuracy, validated through machine learning, along with IHC confirmation and molecular docking insights, supports their potential for both diagnostic and therapeutic applications in IgAN.

Increased risk of adverse events among patients with vs. without systemic autoimmune rheumatic disease prescribed sodium-glucose cotransporter 2 inhibitors: a retrospective cohort study

BACKGROUND

Systemic autoimmune rheumatic disease (SARD) patients have been excluded from sodium-glucose cotransporter 2 inhibitor (SGLT2i) trials given putative risks, but this risk magnitude is unknown. We aimed to quantify SGLT2i adverse event risks among patients with vs. without SARD.   METHODS: In a retrospective cohort study, patients with SARD at Mass General Brigham, a multihospital system in Boston, Massachusetts, prescribed SGLT2i were age-, self-reported race-, and sex-matched to patients prescribed the same SGLT2i between 1/1/2016 and 12/10/2021. Cumulative incidence and Cox models, overall and sex-stratified, estimated patient-reported adverse event risks from prescription date, censoring for discontinuation, death, or study end (12/12/2022).

RESULTS

Four hundred sixty-eight SARD and 420 matched non-SARD patients were compared: mean age 64 years (SD 11.3), 61% female, and 70% White. SARD patients had shorter SGLT2i use duration (8.4 vs. 12.7 months; p < 0.0001) and time to adverse event (0.59 vs. 0.85 years; p 0.04). Yeast infections (9.8% vs. 6.2%; p 0.047) and muscular symptoms (3.4% vs. 1.0%, p 0.01) were more prevalent among those with SARD. Adjusting for baseline demographics, adverse event risk was higher (MV HR 1.68; 95% CI 1.28, 2.21), in patients with vs. without SARD. Risk was higher in women than men overall and in women with SARD vs. without (adjusted HR 1.86; 95% CI 1.36, 2.54).

CONCLUSION

Patients with vs. without SARD had 68% higher adverse event risk with SGLT2i use. Women with vs. without SARD had > 85% higher adverse event risks, although most were not serious. Trials of safety and efficacy of SGLT2i among SARD patients are warranted. Key Points •To our knowledge, this is the first study to compare adverse events associated with SGLT2i utilization in patients with vs. without SARD, despite RCT exclusion and documented SGLT2i use in the population. •In our comparison of 468 patients with SARD and 420 patients without, we identified a greater than 65% increase in risk of adverse event outcomes among patients with SARD. •Furthermore, we found that this risk disproportionately affected female patients, with a 4.4-fold increased risk among women with SARD compared to men without.

SGLT2-Inhibition in Patients With Alport Syndrome

Introduction

Large-scale trials showed positive outcomes of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in adults with chronic kidney disease (CKD). Whether the use of SGLT2i is safe and effective in patients with the common hereditary CKD Alport syndrome (AS) has not yet been investigated specifically in larger cohorts.

Methods

This observational, multicenter, international study (NCT02378805) assessed 112 patients with AS after start of SGLT2i. The study's primary end point was change of albuminuria in albumin/g creatinine from the start of therapy.

Results

Compared to randomized trials investigating the effect of SGLT2i in CKD, the adult patients in this study were younger (aged 38 ± 14 years) and had a better estimated glomerular filtration rate (eGFR, 63 ± 35 ml/min per 1.73 m2; n = 98). Maximum follow-up was 32 months. Compared to baseline, at the first 3 follow-up visits (months 1 to 3, 4 to 8, and 9 to 15) after initiation of SGLT2i therapy, a significant reduction of albuminuria in mg albumin/g creatinine (>30%) was observed. Mean loss of eGFR was 9 ± 12 ml/min per 1.73 m2 almost 1 year after initiation of SGLT2i therapy (n = 35). At a total of 71 patient-years at risk, 0.24 adverse events (AEs) per patient-year on SGLT2i were reported.

Conclusion

This study indicates that, additive to renin-angiotensin system (RAS)-inhibition (RASi), SGLT2i have the potential to reduce the amount of albuminuria in patients with AS. Future studies are needed to investigate the long-term effects of SGLT2i on CKD progression in patients with AS to assess whether the observed reduction in albuminuria translates to a delay in kidney failure (KF).

The Outcomes of IgA Nephropathy With Nephrotic Syndrome: A Clinicopathological Study From Northern India

Introduction Nephrotic syndrome, an unusual clinical presentation of IgA nephropathy (IgAN), occurs only in a few cases. The data regarding its clinical characteristics and treatment outcomes are lacking. Material and methods In this retrospective analysis, we reviewed kidney biopsies conducted between January 2007 and December 2018. All patients with biopsy-proven IgAN and clinical presentation of nephrotic syndrome were included. Results Sixty-seven (11.9%) out of 560 patients with primary IgAN had nephrotic syndrome as the first clinical presentation. On MEST-C scoring, the baseline estimated glomerular filtration rate (eGFR) was significantly lower in the presence of segmental sclerosis (S1) (p=0.04) and >25% tubular atrophy/interstitial fibrosis (T1/2) (p=0.004). With immunosuppression, complete remission (CR), partial remission (PR), and no response (NR) occurred in 28 (41.8%), 32 (47.8%), and 7 (10.4%) patients, respectively. During the median follow-up of 190 weeks, the median absolute change in eGFR was significant between CR and NR groups (p=0.002), and PR and NR groups (p=0.02); however, it was not significant between CR and PR groups (p=0.14). In the CR, PR, and NR groups, 9, 15, and 7 patients had eGFR losses of ≥15 ml/min (p=0.004). No patient in the CR group, one in the PR group, and three in the NR group progressed to end-stage kidney disease (ESKD) (p=0.003). Further, none of the MEST-C scores correlated with the clinical outcome parameters. Conclusion Immunosuppression in treating IgAN accompanied by nephrotic syndrome helps in proteinuria remission. Achieving remission, whether complete or partial, delays disease progression and improves renal survival. Moreover, the baseline eGFR was significantly lower when S1 and T1/2 lesions were present in kidney biopsies.

Clinical Case Scenarios in the Management of Non-diabetic Chronic Kidney Diseases

Research conducted in India has shown that there is a high prevalence of non-diabetic kidney disease (NDKD) among Indian patients. Sodium-glucose co-transporter 2 inhibitors (SGLT2i) are emerging as potential treatments for preventing the progression of chronic kidney disease to advanced stages, regardless of their anti-diabetic effects. Dapagliflozin, which has been approved by the Central Drugs Standard Control Organization, is the SGLT2i drug class approved for use in both DKD and NDKD patients. Taking this validation into account, the case series was planned to showcase four different real-life case studies in an Indian clinical setting, which involved the utilization of dapagliflozin in different patient profiles with NDKD. The real-world cases substantiate the renoprotective effects of dapagliflozin as seen by changes in the estimated glomerular filtration rate levels and proteinuria post-treatment. These case scenarios highlight the benefits of reducing renal risk factors in patients with NDKD. Notably, in all the cases, the risk of renal disease progression was delayed in NDKD patients with dapagliflozin.

Progress of SGLT2 inhibitors in the treatment of common immune-related nephropathies

The immune system can lead to a variety of renal diseases through direct or indirect mechanisms. In immune-mediated nephropathy, though standardized treatment, there are still a small number of patients with further decline in renal function, which may even progress to renal failure; sodium-glucose cotransporter protein 2 (SLC5A2,SGLT2) inhibitors not only can significantly reduce blood glucose, but also have an additional protective effect on the kidneys and the heart; this review concludes the potential mechanism of the renal protective effect of SGLT2i and the new advances in the recent years in common immune-mediated nephropathies, which can provide new theoretical references to optimize the therapeutic strategy of common immune-mediated nephropathies.

Clinical value of adding Dapagliflozin in patients with nephrotic syndrome

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors in nephrotic patients on immunosuppression are underexplored. We evaluated dapagliflozin's impact in non-diabetic primary nephrotic syndrome.

METHODS

Randomized controlled clinical trial was conducted on 60 non-diabetic primary nephrotic syndrome patients, equally assigned to dapagliflozin and control groups. All patients received the standard of care medication and the Dapagliflozin group received 10 mg dapagliflozin in addition. Demographic data, nephrotic syndrome etiology, proteinuria levels, eGFR, and immunosuppression doses, were well-matched. After 6 months of follow up primary outcomes included changes in and eGFR.

RESULTS

Both groups exhibited significant reductions in proteinuria after 6 months, with the dapagliflozin group achieving a mean UPCR reduction of  - 94.7%, and the control group  - 86.7% (p < 0.001). However, the comparative change in proteinuria between both groups did not reach statistical significance (p = 0.158). Dapagliflozin initially led to a transient eGFR decline. Dapagliflozin also resulted in a significant mean body weight reduction (p < 0.001) and notable improvements in triglyceride levels compared to the control group (p = 0.045).

CONCLUSION

In primary nephrotic syndrome patients, adjunct dapagliflozin may enhance the standard of care. While notable, the reduction in proteinuria was comparable to that of the control group by the study's end. Furthermore, after 6 months, eGFR remained stable in both groups. However, significant weight loss and serum triglyceride reduction were particularly pronounced in the dapagliflozin group. Further long-term investigations are necessary to address potential immunosuppression-related confounding effects in patients with primary glomerular disease.

Emerging perspectives in the management of IgA nephropathy: a comprehensive review

IgA nephropathy (IgAN) is the most prevalent form of primary glomerulonephritis worldwide and a leading cause of chronic kidney disease and renal failure. This disorder is characterized by the deposition of immune complexes containing galactose-deficient forms of IgA and complement C3 in the glomeruli. Until now, disease management relied mainly on optimized supportive care. Systemic corticosteroid therapy is proposed for patients at high risk of disease progression, but the effectiveness and safety of this approach are under debate. A significant proportion of patients do not respond to current therapies and require kidney replacement therapy at a young age, with substantial costs and impact on quality of life. Recently, there have been multiple joint efforts to improve the understanding of IgAN pathophysiology. International collaborations resulted in multiple ongoing clinical trials that are providing new insights toward innovative therapeutic options such as SGLT2 inhibitors, dual endothelin and angiotensin receptor blockers, targeted-release budesonide, B-cell proliferation and differentiation inhibitors, and complement system blockers. Based on this new evidence, revision of the guidelines to manage IgAN is expected to occur in the near future. In addition to the novelty in therapeutic agents, there is also a growing interest in new noninvasive biomarkers for IgAN screening, risk stratification to monitor the course of the disease, and the response to treatment. In this review, we discuss current knowledge on the pathophysiology of IgAN, disease management, and emerging advances in clinical translation of IgAN research.

SGLT2 inhibitors across the spectrum of chronic kidney disease: a narrative review

Chronic kidney disease (CKD) is a growing public health concern, affecting at least 1 in 7 adults in the United States, and accounting for a large proportion of healthcare spending. The risk of mortality rises steeply with declining kidney function, mostly due to cardiovascular-related deaths. Since CKD is asymptomatic in the early stages, diagnosis is sometimes delayed. However, early diagnosis is important for timely initiation of interventions to reduce disease progression, and to avoid the need for hospitalizations, dialysis, or kidney transplantation. This review focuses on the impact of sodium glucose transporter 2 inhibitors (SGLT2i) on CKD based on mechanistic and clinical trial evidence. These agents affect the kidneys through changes in sodium transport and metabolic factors that interfere with the primary pathological mechanisms shared by most kidney diseases. Following clinical trials of SGLT2i in patients with type 2 diabetes which demonstrated reductions in the risk of major adverse CV events, death, and hospitalizations for heart failure (HHF), and in patients with heart failure (HF) with and without diabetes which showed reductions in death and HHF, recent trials in patients with CKD have provided overwhelming support for the use of SGLT2i as foundational therapy across a broad spectrum of patients with CKD, regardless of diabetes status, primary kidney disease (except polycystic kidney disease), or kidney function. While clinical trials in CKD generally recruit patients with a high risk of events, patients at lower risk could also benefit from SGLT2i in terms of reduction of CKD progression, HF, and death, as well as other beneficial effects including reductions in blood sugar, body weight, and blood pressure.

Dual blockade of endothelin A and angiotensin II type 1 receptors with sparsentan as a novel treatment strategy to alleviate IgA nephropathy

INTRODUCTION

Although immunoglobulin A nephropathy (IgAN) had been discovered more than 50 years ago, 30-40% of IgAN patients still have primary glomerular disease that progresses to end-stage renal disease. However, various treatment strategies for IgAN have rapidly expanded in recent years to include endothelin (ET) receptor antagonists.

AREAS COVERED

In this review, we discuss the role of the ET-1/ETA receptor axis in the development of IgAN, especially focusing on the potential of sparsentan, a dual ET and angiotensin receptor antagonist as a novel therapy for IgAN.

EXPERT OPINION

Evaluation of the MEST-C score at the time of renal biopsy in IgAN is important in determining treatment strategies. If lesions are mainly in the acute phase, such as crescents, steroid therapy should be continued. However, if lesions are mainly in the chronic phase, such as glomerulosclerosis, sparsentan rather than steroid or angiotensin II receptor blocker alone may improve renal outcomes. Although further clinical studies are needed to back up these assumptions, appropriate combination of new drugs containing sparsentan and conventional drugs for IgAN treatment at the appropriate disease stage is expected to further inhibit the progression of renal damage.

Detecting and managing the patient with chronic kidney disease in primary care: A review of the latest guidelines

Chronic kidney disease (CKD) is a major global health problem, affecting about 9.5% of the population and 850 million people worldwide. In primary care, most CKD is caused by diabetes and/or hypertension, but a substantial proportion of cases may have alternative causes. During the early stages, CKD is asymptomatic, and many people are unaware that they are living with the disease. Despite the lack of symptoms, CKD is associated with elevated risks of cardiovascular disease, progressive kidney disease, kidney failure and premature mortality. Risk reduction strategies are effective and cost-effective but require early diagnosis through testing of the estimated glomerular filtration rate and albuminuria in high-risk populations. Once diagnosed, the treatment of CKD centres around lifestyle interventions, blood pressure and glycaemic control, and preventative treatments for cardiovascular disease and kidney disease progression. Most patients with CKD should be managed with statins, renin-angiotensin-aldosterone system inhibitors and sodium-glucose cotransporter-2 inhibitors. Additional treatment options to reduce cardiorenal risk are available in patients with diabetes, including glucagon-like peptide-1 receptor agonists and non-steroidal mineralocorticoid receptor antagonists. The Kidney Failure Risk Equation is a new tool that can support the identification of patients at high risk of progressive kidney disease and kidney failure and can be used to guide referrals to nephrology. This review summarizes the latest guidance relevant to managing adults with, or at risk of, CKD and provides practical advice for managing patients with CKD in primary care.

Drug repurposing for glomerular diseases: an underutilized resource

Drug repurposing in glomerular disease can deliver opportunities for steroid-free regimens, enable personalized multi-target options for resistant or relapsing disease and enhance treatment options for understudied populations (for example, children) and in resource-limited settings. Identification of drug-repurposing candidates can be data driven, which utilizes existing data on disease pathobiology, drug features and clinical outcomes, or experimental, which involves high-throughput drug screens. Information from databases of approved drugs, clinical trials and PubMed registries suggests that at least 96 drugs on the market cover 49 targets with immunosuppressive potential that could be candidates for drug repurposing in glomerular disease. Furthermore, evidence to support drug repurposing is available for 191 immune drug target-glomerular disease pairs. Non-immunological drug repurposing includes strategies to reduce haemodynamic overload, podocyte injury and kidney fibrosis. Recommended strategies to expand drug-repurposing capacity in glomerular disease include enriching drug databases with glomeruli-specific information, enhancing the accessibility of primary clinical trial data, biomarker discovery to improve participant selection into clinical trials and improve surrogate outcomes and initiatives to reduce patent, regulatory and organizational hurdles.

Application of the updated International IgA Nephropathy Prediction Tool in children one or two years post-biopsy

The pediatric International IgA Nephropathy (IgAN) Prediction Tool comprises two models with and without ethnicity and is the first method to predict the risk of a 30% decline in estimated glomerular filtration rate (eGFR) or kidney failure in children at the time of biopsy using clinical risk factors and Oxford MEST histology scores. However, it is unknown if the Prediction Tool can be applied after a period of observation post-biopsy. Using an international multi-ethnic cohort of 947 children with IgAN, 38% of whom were followed into adulthood, the Prediction Tool was updated for use one year after biopsy. Compared to the original pediatric Prediction Tool, the updated post-biopsy Prediction Tool had a better model fit with higher R2D (51%/50% vs 20%), significant increase in 4-year C-statistics (0.83 vs 0.73/0.69, ΔC 0.09 [95% confidence interval 0.07-0.10] and ΔC 0.14 [0.12-0.15]) and better 4-year calibration with lower integrated calibration indices (0.74/0.54 vs 2.45/1.01). Results were similar after internal validation and when the models were applied two years after biopsy. Trajectories of eGFR after a baseline one year post-biopsy were non-linear and those at higher predicted risk started with a lower eGFR and experienced a more rapid decline over time. In children, eGFR had a variable rate of increase until 15-18 years old and then decreased linearly with a more rapid decline in higher risk groups that was similar to young adults of comparable risk. Thus, the original pediatric Prediction Tool should be used in children at the time of biopsy, and the updated pediatric Prediction Tool should be used to re-evaluate risk one or two years after biopsy.

Podocyte-targeted therapies - progress and future directions

Podocytes are the key target cells for injury across the spectrum of primary and secondary proteinuric kidney disorders, which account for up to 90% of cases of kidney failure worldwide. Seminal experimental and clinical studies have established a causative link between podocyte depletion and the magnitude of proteinuria in progressive glomerular disease. However, no substantial advances have been made in glomerular disease therapies, and the standard of care for podocytopathies relies on repurposed immunosuppressive drugs. The past two decades have seen a remarkable expansion in understanding of the mechanistic basis of podocyte injury, with prospects increasing for precision-based treatment approaches. Dozens of disease-causing genes with roles in the pathogenesis of clinical podocytopathies have been identified, as well as a number of putative glomerular permeability factors. These achievements, together with the identification of novel targets of podocyte injury, the development of potential approaches to harness the endogenous podocyte regenerative potential of progenitor cell populations, ongoing clinical trials of podocyte-specific pharmacological agents and the development of podocyte-directed drug delivery systems, contribute to an optimistic outlook for the future of glomerular disease therapy.

Correlation of Urinary Soluble CD163 Levels With Disease Activity and Treatment Response in IgA Nephropathy

Introduction

The TESTING trial demonstrated that corticosteroids reduce the risk of kidney failure in patients with IgA nephropathy (IgAN) but increase the risk of serious adverse events. Reliable noninvasive biomarkers are needed to identify patients who would benefit most from corticosteroid therapy. Previous studies suggest glomerular macrophage infiltration is associated with response to immunosuppressive therapy in IgAN and urinary soluble CD163 ([u-sCD163], a marker of alternatively activated macrophages [M2]c macrophage) is correlated with clinical remission in vasculitis. This study aims to investigate the association between u-sCD163 and response of steroids therapy in IgAN.

Methods

We measured u-sCD163 in patients from a large IgAN cohort and Chinese participants of the TESTING trial. The correlation of baseline or serial u-sCD163 and their response of corticosteroids therapy or kidney outcomes were investigated.

Results

In cross-sectional analysis, u-sCD163 levels correlated with kidney macrophage infiltration, especially in crescentic areas, and with active lesions. Subgroup analysis of the TESTING cohort showed higher levels u-sCD163 were associated with greater benefits from corticosteroids therapy in proteinuria remission (odds ratio, 35.56 [95% confidence interval, CI: 7.62-292.34] vs. 3.94 [95% CI: 1.39-12.93], P for interaction: 0.036). Corticosteroids therapy significantly reduced u-sCD163 levels at 6 months compared to placebo group (79% [interquartile range: 58%-91%] vs. 37% [-11% to 58%], P <0.001). There was no difference in the suppressive effects on u-sCD163 by either dosage of corticosteroids (full and reduced-dose). The suppression of u-sCD163 was significantly associated with a reduced risk of kidney progression events (adjusted hazard ratio: 0.52, 95% CI: 0.30-0.93, P = 0.027).

Conclusion

u-sCD163 is a reliable noninvasive biomarker associated with active pathological lesions in IgAN and can guide glucocorticoid therapy.

Variants in tubule epithelial regulatory elements mediate most heritable differences in human kidney function

Kidney failure, the decrease of kidney function below a threshold necessary to support life, is a major cause of morbidity and mortality. We performed a genome-wide association study (GWAS) of 406,504 individuals in the UK Biobank, identifying 430 loci affecting kidney function in middle-aged adults. To investigate the cell types affected by these loci, we integrated the GWAS with human kidney candidate cis-regulatory elements (cCREs) identified using single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq). Overall, 56% of kidney function heritability localized to kidney tubule epithelial cCREs and an additional 7% to kidney podocyte cCREs. Thus, most heritable differences in adult kidney function are a result of altered gene expression in these two cell types. Using enhancer assays, allele-specific scATAC-seq and machine learning, we found that many kidney function variants alter tubule epithelial cCRE chromatin accessibility and function. Using CRISPRi, we determined which genes some of these cCREs regulate, implicating NDRG1, CCNB1 and STC1 in human kidney function.

Association of urinary albumin excretion with all-cause and cardiovascular mortality among patients with rheumatoid arthritis: a national prospective study

Background

Rheumatoid arthritis (RA) patients suffering from chronic renal insufficiency tend to exhibit subtle manifestations at the beginning. Urine albumin to creatinine ratio (ACR) is a sensitive indicator for early assessment of renal function. However, it is unclear whether it serves as an independent risk factor influencing the prognosis of RA patients.

Methods

National Health and Nutrition Examination Survey (NHANES) data from 2009-2018 were included. Kaplan-Meier (K-M) curves were plotted to compare the cumulative survival probability of RA patients with different urinary albumin excretion. The association of ACR with mortality among RA patients was investigated with Cox regression model, restricted cubic spline (RCS) and stratified analyses. The prognostic efficacy of ACR and estimated glomerular filtration rate (eGFR) was evaluated by receiver operating characteristic (ROC) curves.

Results

The Cox regression model adjusted with covariates showed a 53% (HR 1.53, 95% CI 1.06-2.21) increase in all-cause mortality and a statistically non-significant increase in cardiovascular disease (CVD) mortality in RA patients with microalbuminuria (30mg/g ≤ACR<300mg/g). ACR≥300mg/g was associated with an increase in all-cause mortality (HR 2.62, 95% CI 1.55-4.45) and CVD mortality (HR 5.67, 95% CI 1.96-16.39). RCS demonstrated a nonlinear correlation between ACR and all-cause mortality in RA patients with microalbuminuria. Subgroup analysis showed that CVD mortality was higher in RA patients with microalbuminuria characterized by the following features: female, other ethnicity, eGFR≥60 ml/min/1.73 m2, hypertension or hyperlipidemia. Compared with eGFR, ACR provided better prognostic efficacy than eGFR with higher values of the area under the curve (AUC) for all-cause mortality (AUC=0.683, 95% CI 0.613-0.754) and CVD mortality (AUC=0.681, 95% CI 0.541-0.820).

Conclusion

ACR is an independent risk factor affecting the prognosis of RA patients. The all-cause mortality was increased in RA patients with albuminuria. There was an upward trend in the CVD mortality of those with macroalbuminuria when ACR increased.

A practical guide to the appropriate analysis of eGFR data over time: A simulation study

In several therapeutic areas, including chronic kidney disease (CKD) and immunoglobulin A nephropathy (IgAN), there is a growing interest in how best to analyze estimated glomerular filtration rate (eGFR) data over time in randomized clinical trials including how to best accommodate situations where the rate of change is not anticipated to be linear over time, often due to possible short term hemodynamic effects of certain classes of interventions. In such situations, concerns have been expressed by regulatory authorities that the common application of single slope analysis models may induce Type I error inflation. This article aims to offer practical advice and guidance, including SAS codes, on the statistical methodology to be employed in an eGFR rate of change analysis and offers guidance on trial design considerations for eGFR endpoints. A two-slope statistical model for eGFR data over time is proposed allowing for an analysis to simultaneously evaluate short term acute effects and long term chronic effects. A simulation study was conducted under a range of credible null and alternative hypotheses to evaluate the performance of the two-slope model in comparison to commonly used single slope random coefficients models as well as to non-slope based analyses of change from baseline or time normalized area under the curve (TAUC). Importantly, and contrary to preexisting concerns, these simulations demonstrate the absence of alpha inflation associated with the use of single or two-slope random coefficient models, even when such models are misspecified, and highlight that any concern regarding model misspecification relates to power and not to lack of Type I error control.

State-of-Art Therapeutics in IgA Nephropathy

Immunoglobulin-A nephropathy (IgAN) is the most common primary glomerulonephritis in the world, with up to 40% of patients progressing to end-stage kidney disease (ESKD) within 30 years of diagnosis. IgAN is characterized by elevated serum levels of galactose-deficient IgA1 (Gd-IgA1), which leads to immune complex formation and deposition in the glomerular mesangium, causing kidney injury. A diverse disease course and the long-term follow-up required for clinically relevant endpoints (e.g., ESKD) have been barriers to the development of novel therapies in IgAN. Disease management has focused on supportive care with inhibitors of the renin-angiotensin system and, more recently, sodium-glucose transporter inhibitors to control proteinuria. The recent acceptance of proteinuria as a surrogate endpoint by regulatory bodies and a better understanding of disease pathology have helped to initiate the development of several novel treatments. Subsequently, a targeted-release formulation of budesonide and a dual endothelin/angiotensin inhibitor (sparsentan) have received accelerated approval for patients with IgAN. However, additional therapies are needed to target the different pathogenic mechanisms and individualize patient care. Several compounds currently under investigation target various effectors of pathology. There are promising clinical results from emerging compounds that target the generation of Gd-IgA1 by B cells, including inhibitors of A PRoliferation-Inducing Ligand (APRIL) and dual inhibitors of APRIL and B-cell activating factor (BAFF). Other investigational therapies target the complement cascade by inhibiting proteins of the lectin or alternative pathways. As the therapeutic landscape evolves, it will be important to revise treatment guidelines and develop updated standards of care.