A Phase 3 Blinded Study of JADE101 in Participants With Immunoglobulin A Nephropathy

Inclusion Criteria: 1. Adult participants with biopsy-confirmed primary IgAN. 2. UPCR ≥0.75 g/g or 24-hour protein excretion ≥1 g/day, as measured from an adequately collected 24-hour urine sample. 3. eGFR ≥30 mL/min/1.73 m². 4. Stable and maximally tolerated doses of ACEi and/or ARB according to standard of care and applicable guidelines for at least 12 weeks prior to the initial screening visit. Exclusion Criteria: 1. Secondary forms of IgAN, or ongoing IgA vasculitis (Henoch-Schönlein purpura) with systemic involvement requiring immunosuppressive treatment. 2. Known or clinically suspected rapidly progressive glomerulonephritis (RPGN). 3. Any chronic infectious disease (e.g., chronic urinary tract infection, chronic sinusitis, bronchiectasis, active pulmonary tuberculosis, or systemic tuberculosis). 4. Body weight \<40 kg or morbid obesity. 5. Receipt of systemic immunosuppressive agents or procedures (including corticosteroids, oral immunosuppressive agents, protocol-specified herbal medicines, or tonsillectomy) within the protocol-defined washout period. 6. Previous or current treatment (including in a prior clinical trial) with anti-APRIL biologics, anti-CD38 therapy, or anti-CD20 therapy. 1. Anti-APRIL biologics 2. Anti-CD38 therapy 3. Anti-CD20 therapy 7. Receipt of an investigational compound or complement inhibitor within 30 days or 5 half-lives (whichever is longer) prior to screening. 8. Presence of or history of nephrotic syndrome, defined as 24-hour urine protein \>3.5 g/day with concurrent hypoalbuminemia. 9. Serum IgG level \<6 g/L (\<600 mg/dL). Other protocol-defined inclusion and exclusion criteria may apply.