To Assess the Efficacy and Safety of Pegcetacoplan for the Prevention of Recurrent C3G or Primary IC-MPGN in Kidney Transplant Recipients

Inclusion Criteria: * Male or female patients with a diagnosis of C3 glomerulopathy (C3G) or primary immune-complex membranoproliferative glomerulonephritis (IC-MPGN) who are planning to undergo kidney transplantation because of the disease. * High risk of disease recurrence following kidney transplantation, defined by either: Previous kidney allograft loss due to recurrent C3G or primary IC-MPGN, or investigator assessment of high recurrence risk based on clinical information. * Up to date with vaccinations against Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae type B, in accordance with local requirements, before initiation of pegcetacoplan. Exclusion Criteria: * A known secondary cause for MPGN, including but not limited to monoclonal gammopathy of clinical significance, hepatitis B, hepatitis C, or autoimmune cryoglobulinemia. * History of invasive meningococcal disease. * History of malignancy, except for the following: cured basal or squamous cell skin cancer, curatively treated in situ disease, or currently malignancy-free and has been off-treatment for the malignancy for at least 5 years. * Hypersensitivity to pegcetacoplan or any of its excipients. * Known or suspected hereditary fructose intolerance. * Any other medical condition which, in the opinion of the Investigator, makes the participant unsuitable for inclusion. * Use of a complement inhibitor for the treatment of C3G or primary IC-MPGN within 1 month prior to the scheduled kidney transplantation surgery.