Kidney Week

Abstract: SA-PO840

Fibrillary Glomerulonephritis Treated with Rituximab and Cyclophosphamide Combination Therapy: A Retrospective Cohort Study

Session Information

• C3G, TMA, MGRS, Amyloidosis, and More
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Sauvage, Gabriel, Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

Gabriel Sauvage

• Zonozi, Reza, Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

Reza Zonozi, MD

• Efe, Orhan, Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

Orhan Efe, MD

• Jeyabalan, Anushya, Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

Anushya Jeyabalan, MD

• Cosgrove, Katherine M., Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

Katherine M. Cosgrove, RN

• Laliberte, Karen A., Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

Karen A. Laliberte, RN

• Niles, John, Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

John Niles, MD

• Al Jurdi, Ayman, Vasculitis and Glomerulonephritis Center, Massachusetts General Hospital, Boston, Massachusetts, United States

Ayman Al Jurdi, MD, FASN

Background

Fibrillary glomerulonephritis (FGN) is a rare kidney disease with a poor prognosis. Over 50% of patients progress to end-stage kidney disease (ESKD) within two years of diagnosis. Currently, no treatments have been shown to reduce the risk of ESKD in individuals with FGN. In this study, we aimed to describe the outcomes of FGN patients treated with a combination induction regimen of rituximab, low-dose oral cyclophosphamide, and prednisone.

Methods

We conducted a single-center retrospective cohort study including all patients with FGN treated at the Vasculitis and Glomerulonephritis Center at the Massachusetts General Hospital in Boston, MA between 2008 and 2024. The primary outcome was defined as the doubling of serum creatinine or the development of ESKD. Progression of kidney disease at the end of the follow-up period was the secondary outcome subdivided into the following categories: non-progressive (increase in serum creatinine by < 25%), progressive (increase in serum creatinine by > 25%), and ESKD (dialysis initiation or transplantation during the study period).

Results

We identified 14 consecutive patients with biopsy-proven FGN. 13 patients were treated with rituximab, low-dose cyclophosphamide, and prednisone, while one patient was treated with rituximab monotherapy. The median (IQR) follow-up was 3.0 (0.9-5.5) years. Five of 14 reached the primary outcome of doubling of serum creatinine or ESKD at a median of 2.8 years. At the end of follow-up, seven (50%) patients were non-progressors, two (14%) were progressors, and five (36%) had developed ESKD. To evaluate the effectiveness of the combination induction regimen, we compared the outcomes of individuals in our cohort to two historical cohorts (Hogan et al. Nephrology Dialysis Transplantation 2014, and Javaugue et al. Am J Kidney Dis 2013). Multivariable Cox regression showed that combination induction immunosuppression was associated with an 80% reduction in the incidence of ESKD (HR = 0.20, 95% CI 0.05-0.83, P = 0.03).

Conclusion

Our results suggest that combination therapy with rituximab, low-dose cyclophosphamide, and prednisone, is associated with a slower progression to ESKD in FGN. Clinical trials are needed to confirm these findings.