Nephrotic Syndrome Study Network

Official title

Nephrotic Syndrome Study Network Under the Rare Diseases Clinical Research Network

Overview

Minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), and Membranous nephropathy (MN), generate an enormous individual and societal financial burden, accounting for approximately 12% of prevalent end stage renal disease (ESRD) cases (2005) at an annual cost in the US of more than $3 billion. However, the clinical classification of these diseases is widely believed to be inadequate by the scientific community. Given the poor understanding of MCD/FSGS and MN biology, it is not surprising that the available therapies are imperfect. The therapies lack a clear biological basis, and as many families have experienced, they are often not beneficial, and in fact may be significantly toxic. Given these observations, it is essential that research be conducted that address these serious obstacles to effectively caring for patients. In response to a request for applications by the National Institutes of Health, Office of Rare Diseases (NIH, ORD) for the creation of Rare Disease Clinical Research Consortia, a number of affiliated universities joined together with The NephCure Foundation the NIDDK, the ORDR, and the University of Michigan in collaboration towards the establishment of a Nephrotic Syndrome (NS) Rare Diseases Clinical Research Consortium. Through this consortium the investigators hope to understand the fundamental biology of these rare diseases and aim to bank long-term observational data and corresponding biological specimens for researchers to access and further enrich.

Detailed description

Idiopathic Nephrotic Syndrome (NS) is a rare disease syndrome responsible for approximately 12% of all causes of end-stage kidney disease (ESRD) and up to 20% of ESRD in children. Treatment strategies for Focal and Segmental Glomerulosclerosis (FSGS), Minimal Change Disease (MCD) and Membranous Nephropathy (MN), the major causes of NS, include high dose prolonged steroid therapy, cyclophosphamide, cyclosporine A, tacrolimus, mycophenolate mofetil and other immunosuppressive agents, which all carry significant side effects. Failure to obtain remission using the current treatment approaches frequently results in progression to ESRD with its associated costs, morbidities, and mortality. In the North American Pediatric Renal Trials and Collaborative Studies (NAPRTCS) registry, half of the pediatric patients with Steroid Resistant Nephrotic Syndrome required renal replacement therapy within two years of being enrolled in the disease registry. FSGS also has a high recurrence rate following kidney transplantation (30-40%) and is the most common recurrent disease leading to allograft loss.

The prevailing classification of Nephrotic Syndrome categorizes patients into FSGS, MCD, and MN, if in the absence of other underlying causes, glomerular histology shows a specific histological pattern. This classification does not adequately predict the heterogeneous natural history of patients with FSGS, MCD, and MN. Major advances in understanding the pathogenesis of FSGS and MCD have come over the last ten years from the identification of several mutated genes responsible for causing Steroid Resistant Nephrotic Syndrome (SRNS) presenting with FSGS or MCD histopathology in humans and model organisms. These functionally distinct genetic disorders can present with indistinguishable FSGS lesions on histology confirming the presence of heterogeneous pathogenic mechanisms under the current histological diagnoses.

The limited understanding of FSGS, MCD, and MN biology in humans has necessitated a descriptive classification system in which heterogeneous disorders are grouped together. This invariably consigns these heterogeneous patients to the same therapeutic approaches, which use blunt immunosuppressive drugs that lack a clear biological basis, are often not beneficial, and are complicated by significant toxicity. The foregoing shortcomings make a strong case that concerted and innovative investigational strategies combining basic science, translational, and clinical methods should be employed to study FSGS, MCD, and MN. It is for these reasons that the Nephrotic Syndrome Study Network is established to conduct clinical and translational research in patients with FSGS/MCD and MN.

Interventions

• Procedure Kidney Biopsy
  Patients scheduled to undergo a clinically indicated kidney biopsy will be requested to consent to an additional renal core, to be set aside until all clinical care is complete.

Primary outcome measures

• Event rate of change in urinary protein excretion and renal function. [Time frame: 60 months]
• Rate of change in renal function. [Time frame: 60 months]

Secondary outcome measures (9)

• Quality of Life: [Time frame: 60 months]
• Malignancies [Time frame: 60 months]
• Infections, Serious and Systemic [Time frame: 60 months]
• Thromboembolic Events [Time frame: 60 months]
• Hospitalization [Time frame: 60 months]
• Emergency Department/ Observation Unit Visit [Time frame: 60 months]
• Acute Kidney Injury [Time frame: 60 months]
• Death [Time frame: 60 months]
• New Onset Diabetes [Time frame: 60 months]

Eligibility criteria

Cohort A (biopsy cohort) Inclusion Criteria:

Patients presenting with an incipient clinical diagnosis for FSGS/MCD or MN or pediatric participants not previously biopsied, with a clinical diagnosis for FSGS/MCD or MN meeting the following inclusion criteria:

• Documented urinary protein excretion ≥1500 mg/24 hours or spot protein: creatinine ratio equivalent at the time of diagnosis or within 3 months of the screening/eligibility visit.
• Scheduled renal biopsy

Cohort B (non-biopsy, cNEPTUNE) Inclusion Criteria:

• Age <19 years of age
• Initial presentation with <30 days immunosuppression therapy
• Proteinuria/nephrotic

• UA>2+ and edema OR
• UA>2+ and serum albumin <3 OR
• UPC > 2g/g and serum albumin <3

Exclusion Criteria (Cohort A\&B):

• Prior solid organ transplant
• A clinical diagnosis of glomerulopathy without diagnostic renal biopsy
• Clinical, serological or histological evidence of systemic lupus erythematosus (SLE) as defined by the ARA criteria. Patients with membranous in combination with SLE will be excluded because this entity is well defined within the International Society of Nephrology/Renal Pathology Society categories of lupus nephritis, and frequently overlaps with other classification categories of SLE nephritis (68)
• Clinical or histological evidence of other renal diseases (Alport, Nail Patella, Diabetic Nephropathy, IgA-nephritis, monoclonal gammopathy (multiple myelomas), genito-urinary malformations with vesico-urethral reflux or renal dysplasia)
• Known systemic disease diagnosis at time of enrollment with a life expectancy less than 6 months
• Unwillingness or inability to give a comprehensive informed consent
• Unwillingness to comply with study procedures and visit schedule
• Institutionalized individuals (e.g., prisoners)

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model

Cohort

Study locations

United States · 39 centers

• University of Southern California-Children's Hospital — Los Angeles
• Stanford University School of Medicine — Palo Alto
• University of California San Francisco Benioff Children's Hospitals — San Francisco
• Lundquist Biomedical Research Institute at Harbor UCLA Medical Center — Torrance
• Children's Hospital Colorado — Aurora
• University of Colorado Anschutz School of Medicine — Aurora
• University of Miami Miller School of Medicine — Miami
• Emory University and Children's Healthcare of Atlanta — Atlanta
• … and 31 more centers

Canada · 5 centers

• York Central Hospital — Richmond Hill
• Scarborough Hospital — Scarborough Village
• Credit Valley Hospital — Toronto
• Sunnybrook Hospital — Toronto
• University Health Network — Toronto

Publications

• Wang CS, Troost JP, Wang Y, Greenbaum LA, Gibson K, Trachtman H, Srivastava T, Reidy K, Kaskel F, Sethna CB, Meyers K, Dell KM, Tran CL, Hingorani S, Lemley KV, Lin JJ, Gipson DS. Determinants of medication adherence in childhood nephrotic syndrome and associations of adherence with clinical outcomes. Pediatr Nephrol. 2022 Jul;37(7):1585-1595. doi: 10.1007/s00467-021-05176-8. Epub 2021 Nov 18. PMID 34796395
• Solagna F, Tezze C, Lindenmeyer MT, Lu S, Wu G, Liu S, Zhao Y, Mitchell R, Meyer C, Omairi S, Kilic T, Paolini A, Ritvos O, Pasternack A, Matsakas A, Kylies D, Wiesch JSZ, Turner JE, Wanner N, Nair V, Eichinger F, Menon R, Martin IV, Klinkhammer BM, Hoxha E, Cohen CD, Tharaux PL, Boor P, Ostendorf T, Kretzler M, Sandri M, Kretz O, Puelles VG, Patel K, Huber TB. Pro-cachectic factors link experimen PMID 34060483
• Kang H, Kim DR, Jung YH, Baek CW, Park YH, In Oh J, Kim WJ, Choi GJ. Pre-warming the Streamlined Liner of the Pharynx Airway (SLIPA) improves fitting to the laryngeal structure: a randomized, double-blind study. BMC Anesthesiol. 2015 Nov 20;15:167. doi: 10.1186/s12871-015-0151-4. PMID 26589142
• Hogan MC, Lieske JC, Lienczewski CC, Nesbitt LL, Wickman LT, Heyer CM, Harris PC, Ward CJ, Sundsbak JL, Manganelli L, Ju W, Kopp JB, Nelson PJ, Adler SG, Reich HN, Holzmann LB, Kretzler M, Bitzer M. Strategy and rationale for urine collection protocols employed in the NEPTUNE study. BMC Nephrol. 2015 Nov 17;16:190. doi: 10.1186/s12882-015-0185-3. PMID 26577187

Identifiers

NCT: NCT01209000 · 6801 · 1U54DK083912 · 1R01DK141114-01A1

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗