Study Assessing the Safety and Efficacy of Pegcetacoplan in Post-Transplant Recurrence of C3G or IC-MPGN

Inclusion Criteria: * At least 18 years of age at screening * Must have clinical and pathologic evidence of recurrent C3G or IC-MPGN * Stable (not improving) or worsening disease, in the opinion of the investigator, in the 2 months preceding the first dose of pegcetacoplan * eGFR ≥15 mL/min/1.73 m2, calculated by the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) creatinine equation for adults * No more than 50% glomerulosclerosis or interstitial fibrosis on the screening renal allograft biopsy * Stable regimen for recurrent C3G/IC-MPGN for at least 4 weeks prior to the screening renal allograft biopsy and from the time of the screening renal allograft biopsy until randomization * Have received required vaccinations against N. meningitidis, S. pneumoniae, and H. influenzae (type B) or agree to receive vaccinations, if applicable vaccination records are not available. Vaccination is mandatory unless documented evidence exists that subjects are non-responders to vaccination. Exclusion Criteria: * Absolute neutrophil count \<1000 cells/mm3 during screening * Previous treatment with pegcetacoplan * Evidence of rejection on the screening renal allograft biopsy that requires treatment * Diagnosis or history of HIV, hepatitis B, or hepatitis C infection or positive serology at screening indicative of infection with any of these viruses * Weight more than 100 kg at screening * Hypersensitivity to pegcetacoplan or any of the excipients * History of meningococcal diseas…