Glomerulonephritis, IGA

To determine the nephroprotective potential of treatment with sparsentan in (1: Cohort A) patients newly-diagnosed with immunoglobulin A nephropathy (IgAN) (ie, incident patients) who have not received prior angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) therapy, and in (2: Cohort B) patients with recurrent IgAN following kidney transplantation.

The purpose of this study is to determine if zigakibart is safe and effective for long-term use in patients with immunoglobulin A nephropathy (IgAN). This is an extension study for patients who have already completed an another zigakibart study.

A study to investigate the impact of iptacopan treatment on the underlying immunopathology in patients with IgAN by assessing changes in key clinical and molecular markers from baseline to 9 months. The study aims to provide insights into the treatment's systemic and kidney-specific aspects by quantifying the change in mesangial C3c containing fragments deposition, as an indicator of complement activation, and evaluating a variety of biomarkers related to kidney function, damage, and disease progression, including but not limited to Oxford MEST-C score.

A central goal of this data repository is to collect data from a large population of subjects with a variety of renal disease states. Cohorts will include subjects with diabetes, inflammatory/autoimmune and transplant related renal conditions. Additionally, the repository will have the capacity to store biospecimens and electronic data in control subjects without established renal disease. This initiative will provide an opportunity to compare data from various disease states and controls with the objective of determining clinical and biological factors that predict disease progression, response to therapy and identify discriminating noninvasive clinical and biological features that predict renal biopsy findings.

This study aims to investigate the relevance of the Tfh/Tfr (Follicular helper T cells/ Follicular regulatory T cells) ratio in patients with IgA nephropathy: * To identify a differential expression of the Tfh/Tfr ratio in patients considered stable or progressive * To predict, at diagnosis, the clinical evolution of the disease (progressive or stable form) in the first year.

The goal of this clinical trial is to evaluate the efficacy and safety of probiotics combined with enteric-coated budesonide capsule in patients with IgA nephropathy on the basis of optimized RAS blockade therapy, and to explore the correlation between the efficacy of probiotics combined with enteric-coated budesonide capsule in the treatment of primary IgA nephropathy and intestinal homeostasis. The main questions it aims to answer are: Dose probiotics combined with enteric-coated budesonide capsule provide a durable reduction in urine protein creatinine ratio (UPCR) in participants, compared with probiotics placebo combined with enteric-coated budesonide capsule? What medical problems do participants have when taking probiotics combined with enteric-coated budesonide capsule? Participants will: Take probiotics combined with enteric-coated budesonide capsules or probiotics placebo combined with enteric-coated budesonide capsules every day for 9.5 month Participate in center site follow-up visits for 13 times Keep a diary of their symptoms and outcomes

The purpose of this clinical trial is to evaluate the long-term efficacy and safety of low-dose oral corticosteroids combined with cyclophosphamide therapy and low-dose corticosteroids monotherapy, on a background of maximal RAS inhibitor therapy, for IgA nephropathy with stage 3 or 4 chronic kidney disease.