‘…completely exhausted and weak, really drained.’: a multinational qualitative interview study of healthcare provider, patient, and caregiver experiences of C3 glomerulopathy and primary (idiopathic) immune complex membranoproliferative glomerulonephritis diagnosis, burden and management

Introduction C3 glomerulopathy (C3G) and primary (idiopathic) immune complex membranoproliferative glomerulonephritis (IC-MPGN) are rare progressive kidney diseases. Due to the rare nature of C3G/primary IC-MPGN, there is a paucity of real-world data on the diagnosis, management, and impact of the diseases on patients and caregivers. Our study used the direct experiences of healthcare professionals (HCPs), patients, and caregivers, to provide insight into the diagnosis/management of C3G/primary IC-MPGN and its burden on patients and caregivers. Methods We conducted a multi-country, cross-sectional, semi-structured, qualitative interview study with HCPs, patients, and caregivers in France, Germany, Italy, Spain, the United Kingdom and the United States between July 2024−January 2025. Nephrologists or internal medicine specialists (France and Spain only) were eligible to participate if they managed at least one patient with a biopsy-confirmed C3G/primary IC-MPGN diagnosis. Patients and informal caregivers were recruited via HCPs, patient advocacy groups, online panels or social media and had to be aged ≥16 years and ≥18 years respectively. Thematic analysis was conducted to identify key response themes. Results A total of 21 HCPs, 13 patients, and 8 caregivers were interviewed. HCPs and patients highlighted that milder symptoms often led to diagnostic delays with HCPs highlighting lack of disease recognition, difficulties accessing specialist care, and patient reluctance to receive a biopsy as barriers to timely diagnosis. Mental and physical fatigue/exhaustion were the most burdensome symptoms according to patients and caregivers, impacting all aspects of the patient’s life. Patients stated that achieving disease stability was a key goal of treatment, however HCPs, patients, and caregivers all stated that treatment options at survey (prior to approval of iptacopan and pegcetacoplan) were limited, with dialysis being particularly burdensome to patients. HCPs were hopeful about future treatment options. Caregivers reported that they provided physical and psychological support and advocated for their patient. Caregiving had a substantial impact on the caregiver’s mental wellbeing. Conclusions Overall, C3G/primary IC-MPGN presented a substantial burden to patients and caregivers, with a need for timely diagnosis, psychological support for patients and caregivers, improved HCP-patient communication, and treatments which target the cause of C3G/primary IC-MPGN to stabilize the disease.