Nefecon and Ambrisentan in IgA Nephropathy

Inclusion Criteria: * Diagnosed with IgA nephropathy by pathological biopsy within 4 years; * Age between 18 and 70 years old; * 0.5g/24h ≤ 24-hour urinary protein; * The estimated glomerular filtration rate (eGFR) calculated using the CKD-EPI formula satisfies: eGFR ≥ 30 mL/min/1.73 ㎡ Exclusion Criteria: * Exclude special pathological or clinical kidney disease types such as crescentic glomerulonephritis (pathological diagnosis\>50%), minimal change nephropathy with IgA deposition, etc; * Exclude secondary IgA nephropathy, including allergic purpura, ankylosing spondylitis, systemic lupus erythematosus, Sjogren's syndrome, viral hepatitis, cirrhosis, rheumatoid arthritis, and mixed connective tissue disease; * Select patients who have experienced any of the following cardiovascular events within the previous 12 weeks: myocardial infarction, unstable angina, ventricular arrhythmia, New York Heart Association class II or above heart failure, stroke, etc; * Within 12 weeks prior to the first medication, systemic use (excluding local and nasal inhalation use) of immunosuppressants, including but not limited to glucocorticoids, cyclophosphamide, azathioprine, mycophenolate mofetil, leflunomide, tacrolimus, cyclosporine, rituximab, Tripterygium wilfordii, etc; Have used an endothelin receptor antagonist within 12 weeks prior to the first medication; * Active tuberculosis patients and untreated latent tuberculosis patients; * Patients with active hepatitis or latent hepatitis B (patients with HBcAb positive and HBV DNA positive); According to the results of the five hepatitis B tests, patients with HBsAg positivity should be excluded; Patients who are HBsAg negative but HBcAb positive, regardless of whether HBsAb is positive or negative, need to be tested for HBV-DNA to determine their condition: if HBV-DNA is positive, the patient needs to be excluded; If HBV-DNA is negative, patients can participate in the trial; * History of immunodeficiency diseases or positive HIV test results (enzyme-linked immunosorbent assay and protein immunoblotting); * Patients diagnosed with malignant tumors within the past 5 years, except for treated basal cell carcinoma of the skin, effectively resected squamous cell carcinoma of the skin, colon polyps, or cervical cancer in situ; * Patients undergoing kidney transplantation; * Pregnant women, lactating women, and men or women with fertility plans during the trial period; * For individuals allergic to human derived biological products; * Patients who have received any clinical trial medication within 4 weeks prior to their first use; * Participants deemed unsuitable by researchers.