Treatment and Disease Burden in Patients with C3G: Multinational Real-World Study Results

Introduction: Patients with complement 3 glomerulopathy (C3G) have poor clinical outcomes although new targeted therapies have very recently been approved. Here, we describe the burden and management of C3G in global clinical practice. Methods: Retrospective analysis of data obtained from a cross-sectional survey (Adelphi Real World C3G Disease Specific Programme™) of nephrologists actively managing C3G (N = 195) and their patients (N = 385) in France, Germany, Italy, Spain, the United Kingdom (EU5), the United States, China, and Japan (July 2022–April 2023). Information on patient demographics, clinical characteristics, diagnosis journey, treatment patterns, dialysis and kidney transplant information, and patient-reported outcomes was collected from nephrologist-completed patient record forms (PRFs) and patient self-completion forms (PSCFs). Results were reported using descriptive statistics. Results: Records for 385 patients with C3G were completed by 129 nephrologists. Most patients had moderate to severe disease at the time of diagnosis (85.1%), based on individual nephrologist assessment. At the time of PRF completion, 83.4% of patients were receiving pharmacological treatment, which included angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (70.4%) and corticosteroids (48.6%). In patients receiving treatment, proteinuria remained the most common nephrologist-reported sign of C3G (66.0%), irrespective of treatment duration; of patients with available data, 68.9% had proteinuria ≥1 g/day. At the time of PRF completion, 8.3% of patients were on dialysis, 41.6% of patients were considered eligible for a kidney transplant, and 6.5% were transplant recipients. Patients experienced anxiety/depression (73.7%), pain/discomfort (65.3%), fatigue (90.7%), and problems doing usual activities (62.7%) at the time of PSCF completion. Conclusion: Despite most patients receiving current guideline-recommended standard of care, the burden of C3G remains high worldwide, demonstrating the need for more effective treatment options. In addition, most patients presented with advanced disease by the time of diagnosis, warranting a need to address significant diagnostic delays to facilitate earlier therapeutic intervention.