From RAAS blockade to regenerative medicine: evolving treatment strategies in Alport syndrome

Alport syndrome (AS) is a hereditary glomerulopathy caused by mutations in the COL4A3, COL4A4, or COL4A5 genes, leading to progressive kidney decline and extrarenal manifestations. Advances in genetic testing have enabled the reclassification of AS into X-linked, autosomal recessive, and autosomal dominant forms, facilitating more accurate diagnosis and risk stratification. While renin-angiotensin-aldosterone system (RAAS) blockade remains the foundation of treatment to delay kidney failure, it does not directly target the underlying molecular pathology. Adjunctive commercially available metabolic modulators, including SGLT2i, mineralocorticoid receptor antagonists, ezetimibe and GLP-1 receptor agonists, may offer additional kidney protection. Ameliorating therapies being tested in Phase II trials include endothelin receptor antagonists (e.g., atrasentan), dual endothelin receptor antagonist and angiotensin II receptor inhibition (e.g., sparsentan) FXR agonists (e.g., vonafexor), inducers of cholesterol efflux (e.g., VAR200 and R3R01), and NOX1/4 inhibitors (e.g., setanaxib), several of which are currently being evaluated in clinical trials. Novel strategies such as exon skipping, gene editing, and nonsense mutation readthrough (e.g., ELX-02) are advancing toward precision medicine approaches as disease modifying agents targeting the genetic cause of AS. Moreover, therapies targeting mitochondrial function, such as mitophagy enhancers, have demonstrated preclinical promise. Stem cell-based approaches are also being explored for their regenerative and anti-fibrotic effects. This review summarizes the current landscape of AS classification and treatment, highlighting both standard interventions and experimental therapies. Emphasis is placed on the molecular mechanisms underlying podocyte injury and fibrosis, recent preclinical findings, and ongoing clinical trials that may shift future therapeutic paradigms.