A Study of SGB-9768 in Patients With Complement-mediated Kidney Diseases

Prior treatment

• Received immunosuppressants or other immunomodulators within 90 days prior to the first administration of the investigational drug
• Received B-cell targeted biologics or other biologics within 180 days prior to the first administration of the investigational drug
• Used SGLT2 inhibitors or endothelin receptor antagonists, unless have been stably used for 12 weeks or more
• History of severe trauma or major surgery within 12 weeks prior to screening, or plans to undergo surgery during the study.

Other illness

• IgA nephropathy, C3 glomerulopathy, or IC-MPGN secondary to other diseases
• Presence of other systemic diseases or kidney diseases that may cause proteinuria
• History of any malignant tumors of any organ system within the past 5 years
• History of immunodeficiency diseases, congenital asplenia or splenectomy.
• History of recurrent invasive infections, active systemic bacterial, viral, or fungal infections
• Positive test results for HBV, HCV, HIV

Lab values

• Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels \> 2.5 times the upper limit of normal (ULN)

Other

• Kidney biopsy indicates more than 50% tubular atrophy or interstitial fibrosis.
• Kidney biopsy shows more than 50% formation of glomerular crescents, or clinical signs suggestive of rapidly progressive glomerulonephritis.
• Significant comorbidities

• Aged ≥18 years
• Weight ≥40 kg, with a body mass index (BMI) between 15 and 35 kg/m²
• Biopsy-confirmed diagnosis of primary IgA nephropathy, C3 glomerulopathy or IC-MPGN, accompanied by C3 deposition in the glomeruli.
• Urine protein-to-creatinine ratio (UPCR) ≥0.75 g/g
• Estimated glomerular filtration rate (eGFR) (calculated using the CKD-EPI formula) must be ≥30 mL/min/1.73 m².
• Must be on a stable maximum tolerated doses of ACE inhibitors (ACEI) or angiotensin receptor blockers (ARB) for at least 12 weeks
• Participants of childbearing potential must use highly effective contraception during the study and for at least 12 weeks following the end of the study or last dose of study drug