This multicenter, open-label, prospective single-arm study will enroll adults (≥18 y) with primary IgA nephropathy confirmed by renal biopsy within 2 weeks, eGFR ≥20 ml/min/1.73 m² and 0.5-3.5 g/d proteinuria, to receive early (real-world) combination therapy with RASI (titrated irbesartan), SGLT2i (dapagliflozin 10 mg qd) and budesonide enteric-coated capsules (16 mg qd) for 9 months, followed by budesonide taper-off and continuation of RASI+SGLT2i for 3 more months (12 months total), with primary endpoint being change in proteinuria from baseline to month 12 and secondary endpoints changes in eGFR and microscopic hematuria.