Paediatric immune-mediated renal disease: an overview

Investigating the use of finerenone in children with chronic kidney disease and proteinuria: design of the FIONA and open-label extension studies

INTRODUCTION

Proteinuria is a modifiable risk factor for chronic kidney disease (CKD) progression in children. Finerenone, a selective, non-steroidal, mineralocorticoid receptor antagonist (MRA) has been approved to treat adults with CKD associated with type 2 diabetes mellitus (T2DM) following results from the phase III clinical trials FIDELIO-DKD (NCT02540993) and FIGARO-DKD (NCT02545049). In a pre-specified pooled analysis of both studies (N = 13,026), finerenone was shown to have an acceptable safety profile and was efficacious in decreasing the risk of adverse kidney and cardiovascular outcomes and of proteinuria.

OBJECTIVE

FIONA and the associated open-label extension (OLE) study aim to demonstrate that combining finerenone with an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) is safe, well-tolerated, and effective in sustainably reducing urinary protein excretion in children with CKD and proteinuria.

DESIGN

FIONA (NCT05196035; Eudra-CT: 2021-002071-19) is a randomized (2:1), double-blind, placebo-controlled, multicenter, phase III study of 6 months' duration in approximately 219 pediatric patients. Patients must have a clinical diagnosis of CKD (an eGFR ≥ 30 mL/min/1.73 m2 if ≥ 1 to < 18 years or a serum creatinine level ≤ 0.40 mg/dL for infants 6 months to < 1 year) with significant proteinuria despite ACEi or ARB usage. The primary objective is to demonstrate that finerenone, added to an ACEi or ARB, is superior to placebo in reducing urinary protein excretion. FIONA OLE (NCT05457283; Eudra-CT: 2021-002905-89) is a single-arm, open-label study, enrolling participants who have completed FIONA. The primary objective of FIONA OLE is to provide long-term safety data. FIONA has two primary endpoints: urinary protein-to-creatinine ratio (UPCR) reduction of ≥ 30% from baseline to day 180 and percent change in UPCR from baseline to day 180. A sample size of 198 participants (aged 2 to < 18 years) in FIONA will provide at least 80% power to reject the null hypothesis of either of the two primary endpoints.

CONCLUSION

FIONA is evaluating the use of finerenone in children with CKD and proteinuria. Should safety, tolerability, and efficacy be demonstrated, finerenone could become a useful additional therapeutic agent in managing proteinuria and improving kidney outcomes in children with CKD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05196035. Registered on 19 January 2022.

Anti-glomerular basement membrane disease in children: a brief overview

Anti-glomerular basement membrane disease (Anti-GBM), previously known as Goodpasture syndrome, is an extremely rare cause of rapidly progressive glomerulonephritis and chronic kidney disease stage 5 (CKD5) in children. It is associated with acute pulmonary haemorrhage and it has a poor prognosis. It is classified as an autoimmune, small-vessel vasculitis caused by autoantibody formation against the alpha-3 chain in type IV collagen found in the glomerular basement membrane. Evidence of anti-GBM antibodies in serum or histologically are required for diagnosis. Treatment in children is based on very limited adult data and often involves the use of acute apheresis to rapidly remove circulating factors coupled with intensive immunosuppression such as cyclophosphamide and intravenous corticosteroids. There is also an emerging role for the use of biologic agents such as B cell depletion. The evidence base in children with anti-GBM disease is extremely limited. Multi-centre international collaboration is required to provide insight into this disease, better describe its prognosis and work towards improving outcomes. This review article summarises the key features of this disease in children, highlights treatment options and considers areas of unmet need.

New-Onset Nephrotic Syndrome in a Child Associated With COVID-19 Infection

Introduction: The COVID-19 outbreak has become a worldwide public health emergency. The renal histopathological features of acute tubular necrosis or thrombotic microangiopathy have been previously reported in adults with severe COVID-19 infections. In children, the renal manifestations associated with COVID-19 disease are not widely reported. Here we describe a case report of a child with new-onset nephrotic syndrome associated with COVID-19 infection. Case Presentation: An 8-year-old boy with no previous significant medical history presented with bilateral eyelid and facial swelling soon after his parents were diagnosed with COVID-19 infection. He had diarrhea but no fever or shortness of breath. At 1 week after the onset of swelling, the boy tested positive for the COVID-19 virus. Based on clinical findings of significant proteinuria (urine protein and creatinine ratio of 11.4), hypoalbuminemia (serum albumin of 2 g/dl), and hypercholesterolemia (total cholesterol of 384 mg/dl), he was diagnosed with nephrotic syndrome. He responded well to standard-dose prednisone treatment for nephrotic syndrome. At 1 week after starting the prednisone treatment, he went into clinical remission. Lymphopenia continued to be present for 4 weeks after the onset of symptoms. There were no complications related to clot formation or secondary infections with this presentation. Conclusion: COVID-19 can be associated with new-onset nephrotic syndrome in children. The patient responded well to the standard-dose prednisone treatment that is typically used for new-onset nephrotic syndrome. Summary: We describe the unique presentation of COVID-19 in a child as new-onset nephrotic syndrome. We offer insight on the success of standard treatment of nephrotic syndrome with COVID-19.