Immunosuppressants or corticosteroids compared with supportive therapy: a systematic review and meta-analysis on the efficacy and safety for IgA nephropathy treatment

Drugs in Development to Treat IgA Nephropathy

IgA nephropathy is a common glomerulonephritis consequent to the autoimmune response to aberrant glycosylated immunoglobulin (Ig) A antibodies. Although it has historically been considered a benign disease, it has since become clear that a substantial percentage of patients reach end-stage kidney failure over the years. Several therapeutic attempts have been proposed, with systemic steroids being the most prevalent, albeit burdened by possible serious adverse events. Thanks to the more in-depth knowledge of the pathogenesis of IgA nephropathy, new treatment targets have been identified and new drugs developed. In this narrative review, we summarise the molecules under clinical development for the treatment of IgA nephropathy. As a search strategy, we used PubMed, Google, ClinicalTrials.gov and abstracts from recent international congresses. TRF budesonide and sparsentan are the two molecules at a more advanced stage, just entering the market. Other promising agents are undergoing phase III clinical development. These include anti-APRIL and anti-BLyS/BAFF antibodies and some complement inhibitors. Other new possible strategies include spleen tyrosine kinase inhibitors, anti-CD40 ligands and anti-CD38 antibodies. In an era increasingly characterised by 'personalised medicine' and 'precision therapy' approaches and considering that the potential therapeutic armamentarium for IgA nephropathy will be very broad in the near future, the identification of biomarkers capable of helping the nephrologist to select the right drug for the right patient should be the focus of future studies.

Current knowledge of targeted-release budesonide in immunoglobulin A nephropathy: A comprehensive review

Immunoglobulin A (IgA) nephropathy is a common autoimmune kidney disease. Accumulating studies showed that IgA nephropathy may be partially correlated with mucosal immune system dysfunction. Systemic corticosteroid treatment exerts an essential protective effect against renal deterioration in IgA nephropathy. However, long-term use of corticosteroids may cause systemic side effects. The novel targeted-release formulation (TRF) of budesonide has been shown to deliver the drug to the distal ileum with the aim of minimizing adverse events for patients with IgA nephropathy. In this review, we have summarized all the current evidence of the effects of TRF-budesonide protecting against IgA nephropathy. Three randomized controlled trials (RCTs), one cohort, two case reports, and an ongoing Phase 3 trial (Part B, NCT03643965), were under comprehensive review. These included studies demonstrated that TRF-budesonide could remarkably reduce proteinuria, hematuria, and creatinine, as well as preserve renal function. The local immunosuppressive effects exhibited by TRF-budesonide may represent a novel and promising approach to treating IgA nephropathy. However, the current evidence was only derived from limited trials. Therefore, more well-designed RCTs are still warranted to validate the curable profile of TRF-budesonide in treating IgA nephropathy.