This study is a multicenter, randomized phase II clinical study to evaluate Efficacy and safety, while observing pharmacokinetic profiles, pharmacodynamic effects, and immunogenicity of CM338 in subjects with Immunoglobulin A(IgA) nephropathy.

In 1968, immunoglobulin A nephropathy (IgAN) was developed by French pathologist Dr. Jean Berger and his colleague Dr. Nicole Hinglais that what is described as glomerular "immunoglobulin A (IgA)-immune globule" - immune globule Protein G (IgG) intercapillary deposition" of kidney disease, the main pathological feature of which is on the glomerulus IgA deposition, usually accompanied by local cell proliferation and stromal dilation. Since there is not enough specificity and spirit Biomarkers of sensitivity, the only way to confirm the diagnosis is renal biopsy.

Inclusion Criteria:

• Male or female aged 18-75.
• Understand the nature of the study and sign the Informed Consent Form voluntarily.
• Take effective contraception measures throughout the study period.

Exclusion Criteria:

• Used other investigational drugs within 30 days before the first study administration.
• With previous history of Human immunodeficiency virus(HIV) infection.
• Treponema pallidum antibody positive in screening period.
• May have active Mycobacterium tuberculosis infection.
• Major surgery is planned during the study.
• Other reasons the investigator believes that the subject is not suitable to participate in this study.