The purpose of this study is to evaluate the efficacy and safety of SHR1459 tablets in patients with primary membranous nephropathy.

This study is a phase II study to evaluate the efficacy and safety of SHR1459 tablets in patients with primary membranous nephropathy.

Inclusion Criteria:

1. Diagnosis of primary membranous nephropathy based on renal biopsy before or during screening
2. Have not received any previous immunosuppressive therapy for primary membranous nephropathy or relapse after the treatment has achieved complete or partial remission (comprehensive judgment and recording by the investigator)
3. PLA2R-Ab titer ≥20RU/mL at screening
4. 24-hour urinary protein ≥ 3.5g/d at screening
5. Have eGFR ≥ 60 mL/min/1.73 m2 (based on CKD-EPI formula) at screening

Exclusion Criteria:

1. Any clue for coexist of secondary membranous nephropathy from medical records, laboratory tests or kidney biopsy
2. Existence of clinically significant infection within 1 month before screening,
3. Severe or not well controlled other complications
4. Abnormal in white blood cell count, neutrophil count, lymphocyte count or platelet count at screening, which were considered unfit for participating judged by investigators
5. ALT > 2 times ULN and/or AST > 2 times ULN and/or bilirubin >2 times ULN at screening
6. Subject has evidence of active, latent, or inadequately treated infection with Mycobacterium tuberculosis
7. Positive of hepatitis B surface antigen, hepatitis C antibody, HIV antibody or syphilis antibody at screening;