An Open-label, Multicenter Study to Assess the Effect of Zigakibart Treatment on Histologic, Circulating, and Excreted Markers of Kidney Disease and Dysfunction in Adult Patients With IgA Nephropathy.

Inclusion Criteria: * Primary IgAN, confirmed by kidney biopsy, within 5 years prior to Screening * eGFR ≥45 mL/min/1.73 m2, based on the 2021 CKD-EPI equation, at Screening * Persistent proteinuria, defined as either * Total Urine Protein ≥0.5 g/day or UPCR ≥0.5 g/g in a 24-hour urine collection, at Screening, despite maximally tolerated dose or poorly tolerated supportive therapy or * IgAN diagnosis \<6 months prior to Screening with Total Urine Protein \>1.5 g/day or UPCR \>1.5 g/g in a 24-hour urine collection, at the time of clinical presentation or diagnosis * Body weight ≥45 kg an…