Delphi Consensus on Surrogate End Points in C3 Glomerulopathy and Primary Immune Complex–Mediated Membranoproliferative Glomerulonephritis
Bibliographic record
Abstract
Introduction: C3 glomerulopathy (C3G) and primary immune complex-mediated membranoproliferative glomerulonephritis (IC-MPGN) are rare kidney diseases driven by complement dysregulation. Proteinuria is a commonly used clinical end point in trials involving these conditions. However, its recognition as a validated end point by regulatory bodies remains limited, despite growing evidence supporting its prognostic value as a surrogate biomarker for the development of kidney failure. The aim of this study was to establish consensus on the clinical relevance of proteinuria as a prognostic and treatment end point in C3G and primary IC-MPGN. Methods: A 2-round modified Delphi process was conducted, informed by literature review and expert input. A steering committee composed of 4 European nephrologists, 1 Canadian nephrologist, and 1 European rheumatologist developed 31 statements covering the following 3 domains: (i) treatment efficacy end points, (ii) current assessment end points, and (iii) the role of proteinuria. Statements formed part of an online survey using a 4-point Likert scale, distributed to a broader panel of nephrologists and kidney pathologists across Europe. Results: Fifty-one and 50 responses were received in rounds 1 and 2. Of the 31 statements, 29 reached consensus (≥ 75% agreement). Key consensus points included the following: (i) reduction in proteinuria preserves long-term kidney function and is a treatment goal; (ii) longitudinal monitoring of proteinuria, alongside other markers is valuable for guiding treatment; (iii) a ≥ 50% proteinuria reduction over 6 months indicates meaningful therapeutic benefit; and (iv) proteinuria < 1 g/d is associated with improved outcomes. Conclusion: This study demonstrates consensus supporting proteinuria as a meaningful treatment end point for C3G and primary IC-MPGN.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".