ACTH Gel in Resistant Focal Segmental Glomerulosclerosis After Kidney Transplantation

Clinical characteristics and favorable treatment responses of recurrent focal segmental glomerulosclerosis or steroid-resistant nephrotic syndrome in children after kidney transplantation

BACKGROUND

Recurrence of focal segmental glomerulosclerosis (FSGS) or steroid-resistant nephrotic syndrome (SRNS) after kidney transplant leads to significant morbidity and potentially earlier allograft loss. To date however, reported rates, risk factors and treatment outcomes have varied widely.

METHODS

We applied computational phenotypes to a multicenter aggregation of electronic health records data from 7 large pediatric health systems in the USA, to identify recurrence rates, risk factors, and treatment outcomes. We refined the data collection by chart review.

RESULTS

From > 7 million patients, we compared children with primary FSGS/SRNS who received a kidney transplant between 2009 and 2020 and who either developed recurrence (n = 67/165; 40.6%) or did not (n = 98/165). Serum albumin level at time of transplant was significantly lower and recipient HLA DR7 presence was significantly higher in the recurrence group. By 36 months post-transplant, complete remission occurred in 58.2% and partial remission in 17.9%. Through 6 years post-transplant, no remission after recurrence was associated with an increased risk of allograft loss over time (p < 0.0001), but any remission showed similar allograft survival and function decline to those with no recurrence. Since treatments were used in non-random fashion, using spline curves and multivariable non-linear analyses, complete + partial remission chance was significantly higher with greater plasmapheresis sessions, CTLA4-Ig doses or LDL-apheresis sessions. Only treatment with anti-CD20, CTLA4-Ig agents, or LDL-apheresis sessions were associated with complete remission. Excluding 25 patients with mutations did not significantly change our results.

CONCLUSIONS

Our contemporary high-risk cohort had higher favorable response rates than most prior reports, from combinations of agents.

Acthar Gel (RCI): A Narrative Literature Review of Clinical and Economic Evidence

Acthar^® Gel (repository corticotropin injection [RCI]) is a naturally sourced complex mixture of adrenocorticotropic hormone analogs and other pituitary peptides used to treat patients with serious and rare inflammatory and autoimmune conditions. This narrative review summarizes the key clinical and economic findings among 9 indications: infantile spasms (IS), multiple sclerosis (MS) relapses, rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), dermatomyositis and polymyositis (DM/PM), ocular inflammatory diseases (primarily uveitis and severe keratitis), symptomatic sarcoidosis, and proteinuria in nephrotic syndrome (NS). Key studies of clinical efficacy and healthcare resource utilization and cost from 1956 to 2022 are discussed. Evidence supports the efficacy of RCI across all 9 indications. RCI is recommended as first-line treatment for IS and is associated with improved outcomes for the other 8 indications, including increased recovery rates in MS relapse; improved disease control in RA, SLE, and DM/PM; real-world effectiveness in patients with uveitis and severe keratitis; improved lung function and reduced corticosteroid use in symptomatic sarcoidosis; and increased rates of partial remission of proteinuria in NS. For many indications, RCI may improve clinical outcomes during exacerbations or when conventional treatments have failed to show a benefit. RCI is also associated with a reduction in the use of biologics, corticosteroids, and disease-modifying antirheumatic drugs. Economic data suggest RCI is a cost-effective, value-based treatment option for MS relapse, RA, and SLE. Other economic benefits have been demonstrated for IS, MS relapses, RA, SLE, and DM/PM, including reduced hospitalizations, lengths of stay, inpatient and outpatient services, and emergency department visits. RCI is considered safe and effective and features economic benefits for numerous indications. Its ability to control relapse and disease activity makes RCI an important nonsteroid treatment option that could help preserve functioning and well-being among patients with inflammatory and autoimmune conditions.

Primary Focal Segmental Glomerulosclerosis Recurrence After Pediatric Renal Transplantation

OBJECTIVES

Focal segmental glomerulosclerosis recurrence after renal transplant occurs frequently in pediatric patients and is associated with poor graft survival when patients reach adulthood. We investigated recurrence rates, recurrence risk factors, management strategies, and long-term graft function among pediatric renal transplant recipients with focal segmental glomerulosclerosis as primary disease.

MATERIALS AND METHODS

We retrospectively evaluated medical records of 34 pediatric patients with primary focal segmental glomerulosclerosis who had undergone renal transplant between 2004 and 2019 at our center. Focal segmental glomerulosclerosis recurrence was diagnosed by the presence of nephrotic range proteinuria after transplant and confirmed by graft biopsy. Preoperative prophylactic plasma exchange was administered to pediatric renal transplant recipients with primary focal segmental glomerulosclerosis. Plasma exchange was also used to treat focal segmental glomerulosclerosis recurrence, with rituximab added if the patient did not respond to plasma exchange.

RESULTS

All patients (male-to-female ratio of 19:15) in our group underwent renal transplant. Mean patient age at the time of transplant was 12.72 ± 5.46 years. Twenty-nine patients received living- related donor allografts (85.3%) and 5 received organs from deceased donors (14.7%). We identified focal segmental glomerulosclerosis recurrence in 5 recipients (14.7%). Time from focal segmental glomerulosclerosis diagnosis to end-stage renal disease and duration of dialysis were shorter in the recurrence group than in the nonrecurrence group (48.4 months [range, 2-90 mo] vs 65.1 months [range, 8-123 mo] and 1.41 ± 0.82 vs 3.18 ± 1.88 years, respectively; P < .05). Donor type and transplant age were similar in both groups. Of those with recurrence who had received plasma exchange and rituximab, 3 patients (75%) had complete remission and 1 patient (25%) had partial remission.

CONCLUSIONS

Prophylactic plasma exchange and the combined plasma exchange-rituximab regimen for treatment of focal segmental glomerulosclerosis recurrence resulted in low recurrence and good remission rates in our pediatric cohort.

Application of adrenocorticotropic hormone in recurrent focal segmental glomerulosclerosis post-transplantation: A case report and literature review

BACKGROUND

The recurrence rate of focal segmental glomerulosclerosis (FSGS) post-renal transplantation is as high as 30%-50%. However, the pathogenesis is unclear. At present, there is no unified standard for the treatment of recurrent FSGS post-transplantation. Its treatment is full of risks and challenges.

METHODS

We report a child with recurrent FSGS with massive proteinuria 6~9 g/m² /day and resistance to plasma exchange (PE) and rituximab (RTX). On the basis of receiving anti-rejection therapy of prednisone, tacrolimus, and mycophenolate mofetil (MMF), we treated the child with adrenocorticotropic hormone (ACTH), and reviewed the literature on the application of ACTH in the recurrence of FSGS post-transplantation.

RESULTS

After 1 year of treatment with ACTH, the patient's urinary protein decreased and fluctuated between 0.6 and 1.1 g/m² /day. The albumin (ALB) and cholesterol (CHOL) returned to the normal range. The patient achieved complete remission after 19 months of ACTH treatment and maintained until now. There was no obvious adverse reaction. Literature review showed that up to February 2021, a total of 8 studies showed the use of ACTH in kidney transplant patients, and all the patients in the study achieved remission.

CONCLUSIONS

ACTH is a potential option for treating recurrent FSGS post-transplantation with fewer side effects and relatively safe for patients. However, further evaluation is needed to better adapt to different populations.

Management of recurrent focal segmental glomerulosclerosis (FSGS) post renal transplantation

BACKGROUND

One of the common GN causing ESKD is focal segmental glomerulosclerosis (FSGS). Recurrence of FSGS post-transplantation can lead to graft loss. Data on management either prophylactically or once recurrence occurs are limited. This review article aims to assess the effective management of patients with FSGS recurrence post-transplantation, looking mainly at recurrence post prophylactic treatment and remission in case of treatment post recurrence.

METHODS

Twenty-three studies were included using the search MeSH terms "FSGS" "recurrence" "adults" "transplantation" "treatment". Search engines used were Pubmed, clinical key, Scopus and Cochrane library. Inclusion criteria were articles covered adult patients with recurrent FSGS post renal transplantation, treatment with rituximab and plasmapheresis, and articles published from 2000 tt2021. Excluded articles were paediatric population, studies with no reported outcomes of the treatment of FSGS, and Patients who received stem cell transplantation or galactose therapy.

RESULTS

Prophylactic PP did not show a reduction in recurrence of FSGS in 2/3 studies. Prophylactic rituximab was shown to reduce recurrence of FSGS in one-study and case reports. Treatment of recurrent FSGS with PP showed responses ranging from 41% to 100%. Only one study did not show improvement with PP use as treatment having a 27% remission. Treatment with rituximab showed variable results, with reports showing remission ranging from 57% to 100%. Whereas other reports showing no response at all. PP prescription reporting was variable. One study suggested intensified PP regimen while in most other studies PP was guided by the response reflected by the reduction of proteinuria.

DISCUSSION

Reviewing the treatment of recurrent FSGS is crucial, as there no consensus on treating FSGS as the disease is not very common in the adult population. The evidence of different modalities is based on small cohort studies. This paper supports the use of PP and RTX as treatment of recurrent FSGS.

CONCLUSIONS

In conclusion, PP and RTX are the main modalities to treat recurrent FSGS with varying response rates. Prophylactic PP does not play a role in preventing recurrent FSGS. Prophylactic rituximab might play a role in preventing FSGS post-transplantation. PP and RTX, when used as a treatment, show variable response rates. Larger RCTs are needed to have a strong level of evidence to base our clinical management on.

Adrenocorticotropic hormone: An expansion of our current understanding of the treatment for nephrotic syndrome

In clinical practice, we may encounter a treatment dilemma where in some patients with nephrotic syndrome are resistant to glucocorticoids or immunosuppressive agents. Thus, we currently lack viable treatment options and eagerly await the availability of new drugs. Adrenocorticotropic hormone (ACTH) had earlier been used to treat nephrotic syndrome in children, but has now become less popular owing to the advent of oral glucocorticoids. However, in recent studies, ACTH was reportedly used again for treating nephrotic syndrome, reducing proteinuria and protecting renal function, indicating a possibility for its use in the treatment of refractory nephrotic syndrome. This review analysed the validity of ACTH in these studies, focusing on the mechanism of action, application in both paediatric and adult patients with nephrotic syndrome, particularly in children, and possible side effects. We anticipate that our findings will help clinicians in treatment decision-making.

Recurrent Glomerular Disease after Kidney Transplantation: Diagnostic and Management Dilemmas

Recurrent glomerular disease after kidney transplant remains an important cause of allograft failure. Many of the different entities post-transplant still suffer from incomplete knowledge on pathophysiology, and therefore lack targeted and effective therapies. In this review, we focus on specific clinical dilemmas encountered by physicians in managing recurrent glomerular disease by highlighting new insights into the understanding and treatment of post-transplant focal segmental glomerulosclerosis, membranous nephropathy, atypical hemolytic uremic syndrome, C3 glomerulopathy, amyloid light-chain (AL) amyloidosis, and IgA nephropathy.

Pharmacokinetics and Pharmacodynamics of Repository Corticotropin Injection Compared With Synthetic ACTH1-24 Depot and Methylprednisolone in Healthy Subjects

Repository corticotropin injection (RCI; Acthar Gel) is a naturally sourced complex mixture of adrenocorticotropic hormone (ACTH) analogs and other pituitary peptides. This phase 1, single-center, open-label, randomized parallel study directly compared the pharmacokinetics and pharmacodynamics of RCI and synthetic ACTH_1-24 depot. Methylprednisolone was included to estimate the steroidogenic exposure of RCI and synthetic ACTH_1-24 depot when used to treat nephrotic syndrome. A total of 48 healthy subjects aged 18 to 50 years were randomly assigned 1:1:1 to RCI (80 IU subcutaneously twice weekly on study days 1 and 4), synthetic ACTH_1-24 depot (1 mg subcutaneously twice weekly on study days 1 and 4), or methylprednisolone (32 mg orally once daily on study days 1 through 6). After 2 doses, RCI induced about 5-fold lower free cortisol exposure and an estimated 4-fold lower steroidogenic exposure than synthetic ACTH_1-24 depot. The lower endogenous cortisol response of RCI was achieved despite higher observed mean plasma concentrations of N25-deamidated porcine ACTH_1-39 (the pharmacokinetic marker for RCI) than of ACTH_1-24 . The different pharmacodynamic properties demonstrated by RCI and synthetic ACTH_1-24 depot in this study suggest that these products in the ACTH class are not interchangeable.

Recurrent Focal Segmental Glomerulosclerosis After Kidney Transplantation in African Americans: Review of the Current Evidence

OBJECTIVES

In many countries of sub-Saharan Africa, the most common causes of end-stage kidney disease are hypertension, chronic glomerulonephritis, and diabetes mellitus. So far, literature on recurrent focal segmental glomerulosclerosis in sub-Saharan African populations is limited. With the intention of providing guidance for best practices in sub-Saharan Africa, we reviewed available evidence for African Americans, a population with a similar genetic background. We chose this population as a pseudo-population to show how similar genetic backgrounds can predict disease occurrence in similar populations residing in different continents.

MATERIALS AND METHODS

Our extended PubMed and Scopus literature search used these key words: "focal segmental glomerulosclerosis in African Americans" (search 1), "recurrent focal segmental glomerulosclerosis after kidney transplantation" (search 2), "risk factors for recurrent focal segmental glomerulosclerosis" (search 3); and "APOL1 gene and kidney transplantation" (search 4).

RESULTS/CONCLUSIONS

Search 1 yielded 4 articles, search 2 yielded 44 articles, search 3 yielded 6 articles, and search 4 yielded 8 articles. African Americans were shown to be disproportionately predisposed to endstage kidney disease, traceable to focal segmental glomerulosclerosis (the most common cause of glomerulonephritis leading to end-stage kidney disease). Apolipoprotein L1 presence in 22% of African Americans explained the odds ratio of 17 in developing focal segmental glomerulosclerosis and 8 times lifetime risk of end-stage kidney disease. Focal segmental glomerulosclerosis recurred in 30% of kidney transplant recipients; risk factors included young age, rapid progression to end-stage kidney disease, and White race recipient. Circulating permeability factors played a central role in primary and recurrent focal segmental glomerulosclerosis. For recurrent cases, transplant biopsy has remained the gold standard for diagnosis, with treatment involving a multi-modal approach, often resulting in partial or complete remission of proteinuria; allograft loss can occur if treatment is not successful. More randomized clinical trials are needed to chart the way forward for prolonged allograft function.

Immune-mediated entities of (primary) focal segmental glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) represents a glomerular scar formation downstream of various different mechanisms leading to podocytopathy and podocyte loss. Recently, significant advances were made in understanding genetic factors, podocyte intrinsic mechanisms, and adaptive mechanisms causing FSGS. However, while most cases of nephrotic FSGS are being treated with immunosuppressants, the underlying immune dysregulation, involved immune cells, and soluble factors are only incompletely understood. Thus, we here summarize the current knowledge of proposed immune effector cells, secreted soluble factors, and podocyte response in immune-mediated (primary) FSGS.

Therapeutic Options for Recurrence of Primary Focal Segmental Glomerulonephritis (FSGS) in the Renal Allograft: Single-Center Experience

Focal Segmental Glomerulosclerosis (FSGS) recurrence after kidney transplantation (KTx) is relatively frequent and is associated with poor graft survival. The aim of this study was to investigate which management strategies were associated with better outcomes in our cohort of KTx recipients with primary FSGS. We retrospectively collected data on patients with primary FSGS who received a KTx between 1993 and 2019. A history of biopsy proven FSGS in native kidneys and new onset of significant proteinuria early post-KTx led to the diagnosis of recurrence, which was confirmed by graft biopsy. From 1993 to 2019 we performed 46 KTxs in patients with primary FSGS. We identified 26 episodes of recurrence in 25 patients, 67% of them occurring in males. They were younger at the time of KTx (33.8 vs. 41.1 years old, p = 0.067) and had progressed to end stage renal disease (ESRD) faster after FSGS diagnosis (61.4 vs. 111.2 months, p = 0.038), while they were less likely to have received prophylactic plasmapheresis (61.5% vs. 90%, p = 0.029). 76.7% of recurrences were found early, after a median of 0.5 months (IQR 0.1-1) with a median proteinuria was 8.5 (IQR 4.9-11.9) g/day. All patients with recurrence were treated with plasmapheresis, while 8 (30.7%) additionally received rituximab, 1 (3.8%) abatacept, and 4 (15.4%) ACTH. 7 (27%) patients experienced complete and 11 (42.3%) partial remission after a mean time of 3 (±1.79) and 4.4 (±2.25) months, respectively. Prognosis was worse for patients who experienced a recurrence. Eleven (42.3%) patients lost their graft from FSGS in a median time of 33 (IQR 17.5-43.3) months. In this series of patients, primary FSGS recurred frequently after KTx. Prophylacic plasmapheresis was shown efficacious in avoiding FSGS recurrence, while timely diagnosis and plasmapheresis-based regimens induced remission in more than half of the patients.

Angiotensin II receptor 1 antibodies associate with post-transplant focal segmental glomerulosclerosis and proteinuria

BACKGROUND

Angiotensin II type 1 receptors (AT1Rs) are expressed on podocytes, endothelial and other cells, and play an essential role in the maintenance of podocyte function and vascular homeostasis. The presence of AT1R antibodies (AT1R-Abs) leads to activation of these receptors resulting in podocyte injury and endothelial cell dysfunction. We assessed the correlation between AT1R-Abs and the risk of post-transplant FSGS.

METHODS

This is a retrospective study, which included all kidney transplant recipients with positive AT1R-Abs (≥ 9 units/ml), who were transplanted and followed at our center between 2006 and 2016. We assessed the development of biopsy proven FSGS and proteinuria by urine protein to creatinine ratio of ≥1 g/g and reviewed short and long term outcomes.

RESULTS

We identified 100 patients with positive AT1R-Abs at the time of kidney transplant biopsy or proteinuria. 49% recipients (FSGS group) had biopsy-proven FSGS and/or proteinuria and 51% did not (non-FSGS group). Pre-transplant hypertension was present in 89% of the FSGS group compared to 72% in the non-FSGS group, p = 0.027. Of the FSGS group, 43% were on angiotensin converting enzyme inhibitors or angiotensin receptor blockers prior to transplantation, compared to 25.5% in the non-FSGS group, p = 0.06. Primary idiopathic FSGS was the cause of ESRD in 20% of the FSGS group, compared to 6% in the non-FSGS group, p = 0.03. The allograft loss was significantly higher in the FSGS group 63% compared to 39% in non-FSGS. Odds ratio and 95% confidence interval were 2.66 (1.18-5.99), p = 0.017.

CONCLUSIONS

Our data suggest a potential association between AT1R-Abs and post-transplant FSGS leading to worse allograft outcome. Therefore, AT1R-Abs may be considered biomarkers for post-transplant FSGS.

Repository corticotropin injection versus corticosteroids for protection against renal damage in a focal segmental glomerulosclerosis rodent model

Background

Focal segmental glomerulosclerosis (FSGS) causes renal fibrosis and may lead to kidney failure. FSGS and its common complication, proteinuria, are challenging to treat. Corticosteroids are ineffective in many patients with FSGS, and alternative treatments often yield suboptimal responses. Repository corticotropin injection (RCI; Acthar® Gel), a naturally sourced complex mixture of purified adrenocorticotropic hormone analogs and other pituitary peptides, may have beneficial effects on idiopathic FSGS via melanocortin receptor activation.

Methods

Two studies in a preclinical (female Sprague-Dawley rats) puromycin aminonucleoside FSGS model assessed the effect of RCI on renal function and morphology: an 8-week comparison of a single RCI dose with methylprednisolone (N = 27), and a 12-week chronic RCI dose range study (N = 34). Primary outcomes were proteinuria and renal pathology improvements for measures of renal fibrosis, tubular damage, glomerular injury, and total kidney injury score. Impact of RCI treatment was also determined by assessing urinary biomarkers for renal injury, podocyte expression of podoplanin (a biomarker for injury), podocyte effacement by electron microscopy, and histological staining for fibrosis biomarkers.

Results

Compared with saline treatment, RCI 30 IU/kg significantly reduced proteinuria, with a 38% reduction in peak mean urine protein levels on day 28 in the 8-week model, and RCI 10 IU/kg, 30 IU/kg, and 60 IU/kg reduced peak mean urine protein in the 12-week model by 18, 47, and 44%, respectively. RCI also showed significant dose-dependent improvements in fibrosis, interstitial inflammation, tubular injury, and glomerular changes. Total kidney injury score (calculated from histopathological evaluations) demonstrated statistically significant improvements with RCI 30 IU/kg in the 8-week study and RCI 60 IU/kg in the 12-week study. RCI treatment improved levels of urinary biomarkers of kidney injury (KIM-1 and OPN), expression of podoplanin, and podocyte morphology. RCI also reduced levels of desmin and fibrosis-associated collagen deposition staining. Methylprednisolone did not improve renal function or pathology in this model.

Conclusions

These results provide evidence supporting the improvement of FSGS with RCI, which was superior to corticosteroid treatment in this experimental model. To the authors’ knowledge, this is the first evidence that a drug for the treatment of FSGS supports podocyte recovery after repeated injury.

ACTH Treatment for Management of Nephrotic Syndrome: A Systematic Review and Reappraisal

BACKGROUND

In recent years, the use of adrenocorticotropic hormone (ACTH) therapy for treatment of proteinuria due to nephrotic syndrome (NS) has been heavily explored. ACTH therapy, which comes in the natural (H. P. Acthar Gel) or synthetic (tetracosactide) form, has resulted in remission in patients with immunosuppressive and steroid-resistant NS. However, the exact efficacy of ACTH therapy in the NS etiologies, such as membranous nephropathy (MN), focal segmental glomerulosclerosis (FSGS), minimal change disease (MCD), lupus nephritis (LN), IgA nephropathy (IgAN), and membranoproliferative glomerulonephritis (MPGN), has not been determined.

OBJECTIVE

This systematic review analyzed the published literature on ACTH therapy in various NS etiologies to determine its efficacy.

METHODS

A comprehensive search of MEDLINE, EMBASE, and Cochrane databases was conducted for articles through June 2019. An additional search was performed on clinicaltrials.gov to search for additional trials and cross reference the results of our database search. The literature which studied synthetic or natural ACTH treatment in patients with known etiologies of NS was included. Studies were excluded when they consisted of a single case report or did not analyze the lone effect of ACTH in NS.

RESULTS

The initial search yielded a total of 411 papers, and 22 papers were included. In 214 MN patients, there was an overall remission of 40% (85/214) and an overall remission of 43% (42/98) in FSGS patients. In other etiologies, there were overall remissions of 78% (11/14), 31% (5/16), 40% (16/40), and 62% (8/13) in MCD, LN, IgAN, and MPGN patients, respectively.

CONCLUSION

ACTH showed benefits in proteinuria reduction across all etiologies of NS. However, more randomized controlled studies with larger population sets and longer follow-ups are imperative to establish causal benefits. New studies into its efficacy in children are also necessary.

Adrenocorticotropic Hormone in the Treatment of Focal Segmental Glomerulosclerosis Following Kidney Transplantation

This retrospective study examined the effect of adrenocorticotropic hormone therapy on remission of recurrent focal segmental glomerulosclerosis (FSGS) in patients with history of kidney transplant (KT) treated at 2 transplant centers. Patients with biopsy-confirmed FSGS following KT who received Acthar Gel (Mallinckrodt ARD, Bedminster, New Jersey, United States) treatment for ≥1 month were eligible. A total of 14 patients with idiopathic FSGS were included. Acthar Gel treatment resulted in complete remission of FSGS in 3 patients and partial remission in 2 patients for a total treatment response rate of 36% (5/14) of patients. Among patients showing complete or partial remission, Acthar Gel treatment duration ranged from 6 months to 2 years and 60% (3/5 patients) had serum creatinine ≤ 2 mg/dL at the start of Acthar Gel treatment. Patient outcomes suggest Acthar Gel may be an effective and tolerable treatment for recurrent FSGS in patients with history of KT. Early initiation of Acthar Gel treatment and therapy duration of at least 6 months may be needed for optimal response to Acthar Gel in patients with history of KT and recurrent FSGS.

From podocyte biology to novel cures for glomerular disease

The podocyte is a key component of the glomerular filtration barrier. Podocyte dysfunction is central to the underlying pathophysiology of many common glomerular diseases, including diabetic nephropathy, glomerulonephritis and genetic forms of nephrotic syndrome. Collectively, these conditions affect millions of people worldwide, and account for the majority of kidney diseases requiring dialysis and transplantation. The 12th International Podocyte Conference was held in Montreal, Canada from May 30 to June 2, 2018. The primary aim of this conference was to bring together nephrologists, clinician scientists, basic scientists and their trainees from all over the world to present their research and to establish networks with the common goal of developing new therapies for glomerular diseases based on the latest advances in podocyte biology. This review briefly highlights recent advances made in understanding podocyte structure and metabolism, experimental systems in which to study podocytes and glomerular disease, disease mediators, genetic and immune origins of glomerulopathies, and the development of novel therapeutic agents to protect podocyte and glomerular injury.