A phase 3 clinical trial, APPLAUSE-IgAN, has shown promising results in patients with immunoglobulin A nephropathy (IgAN) treated with iptacopan. The study found that iptacopan significantly reduced proteinuria, a key indicator of kidney function, by 38.3% compared to placebo at 9 months. Iptacopan is an oral Factor B inhibitor of the alternative complement pathway that was recently approved by the FDA for the treatment of paroxysmal nocturnal hemoglobinuria. The trial included over 500 patients with IgAN and evaluated the drug’s efficacy and safety over 24 months. The results suggest that iptacopan may be a valuable new treatment option for IgAN, a progressive kidney disease affecting up to 30% of patients with persistently high proteinuria. Iptacopan’s specific targeting of the alternative complement pathway represents a novel approach to treating IgAN, offering hope for improved outcomes and reduced disease progression.