Immunoglobulin A nephropathy (IgAN), an immune-mediated kidney disease, is particularly prevalent among individuals of East Asian ancestry. Nefecon is a novel, oral, targeted-release budesonide formulation designed to inhibit galactose-deficient-IgA1 formation underlying IgAN pathophysiology. We present findings in patients with IgAN from mainland China participating in the 2-year, multicenter, randomized, double-blind, phase 3 NefIgArd trial of Nefecon. Patients (aged ≥18 years) with primary IgAN (estimated glomerular filtration rate [eGFR] 35-90 ml/min per 1.73 m2, persistent proteinuria [urine protein-creatinine ratio ≥0.8 g/g or proteinuria ≥1 g/24 h] despite optimized renin-angiotensin system blockade) received Nefecon or placebo over 9 months, followed by a 15-month follow-up phase on supportive care alone. The primary efficacy end point was time-weighted average of eGFR over 2 years. Sixty-two patients from mainland China were included in this prespecified analysis. The primary efficacy end point was 9.6 ml/min per 1.73 m2 (95% confidence interval [CI], 2.0 to 19.8) in favor of Nefecon versus placebo. This was consistent with (and numerically greater than) that of the global study population. Time to confirmed 30% eGFR reduction or kidney failure from baseline was substantially delayed with Nefecon (patients with an event: 9%) versus placebo (30%; hazard ratio, 0.21; 95% CI, 0.04 to 0.73]). No deaths were reported in the China cohort. In the Nefecon group, treatment-emergent serious adverse events were reported by one patient during treatment and two patients during follow-up (versus no patients and seven patients, respectively, in the placebo group). No severe infections requiring hospitalization were reported. Nefecon treatment for 9 months showed greater preservation of eGFR over 2 years compared with placebo. The efficacy outcomes were consistent with global study results, with a numerically greater treatment benefit observed in patients from China. Nefecon was well tolerated, with no unexpected safety signals.