A Study to Assess Effectiveness and Safety of Efgartigimod in Chinese Patients With Lupus Nephritis (ZL-1103-013)

Inclusion Criteria: * Aged ≥18 years when signing the informed consent form (ICF) * Capable of providing signed informed consent, and complying with protocol requirements * Diagnosis of SLE according to the Systemic Lupus Erythematosus International Collaborating Clinic (SLICC) 2012 classification criteria * Active, proliferative LN Class III or IV \[excluding Class III (C), IV-S (C), and IV-G (C)\], either with or without the presence of Class V using the 2003 International Society of Nephrology (ISN)/Renal Pathology Society (RPS) criteria, proven by kidney biopsy within 6 months before randomization and confirmed by the central biopsy reading group * Require LN induction therapy (glucocorticoids and MMF/MPA) based on investigator's clinical judgment. Induction therapy may begin before screening but should be initiated within 60 days before randomization * Agree to use contraceptives consistent with local regulations. Full inclusion criteria can be found in the protocol Exclusion Criteria: * Active or chronic infection requiring treatment * Any evidence of central nervous system lupus (including but not limited to seizures, psychosis, organic brain syndrome, cerebrovascular accident, cerebritis, or CNS vasculitis) * Currently on renal dialysis or expected to require dialysis during study period * Previous kidney transplantation or planned transplantation during study period * History of malignancy unless deemed cured by adequate treatment with no evidence of recurrence for ≥3 years before randomization. The following cancers are not exclusionary: basal cell or squamous cell skin cancer; carcinoma in situ of the cervix; carcinoma in situ of the breast; incidental histological finding of prostate cancer * Heart failure due to Systemic Lupus Erythematodes, or any other severe cardiovascular involvement with safety concerns according to investigator's judgment * Any other known autoimmune disease that would interfere with an accurate assessment of clinical symptoms of SLE/LN or put the participant at undue risk * Previously failed treatment with MMF or any form of mycophenolate-based induction therapy, based on the investigator's opinion * Use of complementary therapies, including Traditional Chinese Medicine, herbs, or procedure (eg, acupuncture) that can potentially interfere with the efficacy and safety of participants as assessed by the investigator * SARS-CoV-2 antigen-based positive test at screening. The test is required regardless of whether the participant has been vaccinated * Known hypersensitivity or contraindication to efgartigimod, any excipient of the IMP, or SoC medication used in the study * In the opinion of the investigator, current or history of (ie, within 12 months of randomization) alcohol, drug, or medication abuse * Pregnant or lactating females and those who intend to become pregnant during study participation * Any conditions or circumstances that in the opinion of the investigator may make the participant unsuitable for the study The full list of criteria can be found in the protocol.