A Study to Assess Effectiveness and Safety of Efgartigimod in Chinese Patients with Primary Membranous Nephropathy (ZL-1103-014)

Inclusion Criteria:

• Aged ≥18 years when signing the informed consent form (ICF)

• Capable of providing signed informed consent and complying with protocolrequirements

• Diagnosis of idiopathic (primary) MN confirmed by renal biopsy within 24 monthsbefore randomization. A renal biopsy may be taken at any time during the screeningperiod to confirm the diagnosis of MN for participant eligibility, if the mostrecent biopsy was performed greater than 24 months before randomization

• Receiving stable dose at maximum tolerated or allowed dose of ACEi and/or ARB for atleast 12 weeks before randomization

• Agree to use contraceptives consistent with local regulations. Full inclusioncriteria can be found in the protocol

Exclusion Criteria:

• Active or chronic infection requiring treatment

• Diagnostic renal biopsy showing evidence of crescent formation in glomeruli,suggestive of an alternative or additional diagnosis to pMN; evidence on renalbiopsy of >50% interstitial fibrosis/tubular atrophy in the cortical area

• History of malignancy unless deemed cured by adequate treatment with no evidence ofrecurrence for ≥3 years before randomization.

• Any evidence of diabetic glomerulopathy on renal biopsy that is:

Greater than Class I diabetic glomerulopathy, or Class I diabetic glomerulopathy with a history of poor diabetic control (eg, HbA1c ≥9.0%) since time of biopsy

• Currently on renal dialysis or expected to require dialysis during study period

• Previous kidney transplantation or planned transplantation during study period

• Any other known autoimmune disease that, requires systemic immunosuppressivetreatments, or in the opinion of the investigator, would interfere with an accurateassessment of clinical symptoms of pMN or put the participant at undue risk

• Clinical evidence of other significant or uncontrolled serious diseases (ie,cardiovascular, pulmonary, hematologic, gastrointestinal, hepatic, renal,neurological), have had a recent major surgery, or have any other condition, that inthe opinion of the investigator, could confound the results of the study or put theparticipant at undue risk

• Use of complementary therapies, including Traditional Chinese Medicine, herbs, orprocedures (eg, acupuncture) within 4 weeks before randomization that canpotentially interfere with the efficacy and safety of participants as assessed bythe investigator

• Received live/live-attenuated vaccine within 28 days before randomization. Thereceipt of any inactivated, subunit, polysaccharide, or conjugate vaccine at anytime before screenings is not considered exclusionary. It is recommended thatparticipants are up to date with vaccination before the first dose of IMP

• Previously participated in a clinical study with efgartigimod

• SARS-CoV-2 positive test at screening. The test is required regardless of whetherthe participant has been vaccinated

• Known hypersensitivity or contraindication to efgartigimod, or any excipient of theIMP

• In the opinion of the investigator, current or history of (ie, within 12 months ofrandomization) alcohol, drug, or medication abuse

• Pregnant or lactating females and those who intend to become pregnant during studyparticipation

• Any conditions or circumstances that in the opinion of the investigator may make theparticipant unsuitable for the study