Kidney Week

Abstract: TH-PO608

Primary FSGS Patient Response to Immunosuppression (IS) and Risk of ESKD

Session Information

• Membranous Nephropathy, FSGS, and Minimal Change Disease
  October 24, 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

• Sim, John J., Kaiser Permanente Southern California, Pasadena, California, United States

John J. Sim, MD, FASN

• Munis, Mercedes A., Kaiser Permanente Southern California, Pasadena, California, United States

Mercedes A. Munis, MPH

• Chen, Qiaoling, Kaiser Permanente Southern California, Pasadena, California, United States

Qiaoling Chen, MS

• Hill, T. Matthew, Otsuka America Pharmaceutical Inc, Rockville, Maryland, United States

T. Matthew Hill, PharmD, PhD

• Zhuo, Min, Visterra Inc, Waltham, Massachusetts, United States

Min Zhuo, MD, MPH, FASN

• Lewing, Benjamin, Otsuka America Pharmaceutical Inc, Rockville, Maryland, United States

Benjamin Lewing, MA, MS, PhD

• Harrison, Teresa N., Kaiser Permanente Southern California, Pasadena, California, United States

Teresa N. Harrison

• Fernandes, Ancilla, Otsuka America Pharmaceutical Inc, Rockville, Maryland, United States

Ancilla Fernandes, MS, PhD

• Schachter, Asher Daniel, Visterra Inc, Waltham, Massachusetts, United States

Asher Daniel Schachter, MD, MS

Background

Primary FSGS is a podocytopathy with variability in response to IS which may affect subsequent outcomes. We compared ESKD outcomes between IS responsive vs non-responsive pts with primary FSGS.

Methods

Retrospective cohort study of Kaiser Permanente Southern California pts (≥18yo) with biopsy confirmed primary FSGS and treated with IS (2010-2021). Treatment response within 8-months was categorized as IS responsive (urine protein to creatinine ratio [UPCR] decline of >50% from baseline AND UPCR ≤3.5g/g ) or IS non-responsive. ESKD was defined as treatment with kidney transplant or dialysis. Multivariable Cox proportional hazard models used to estimate hazard ratios (HR) for ESKD. IS was implemented as a time-dependent covariate and Fine-Gray method utilized for the competing risk of mortality.

Results

Among 230 patients treated with IS, 125 (54%) responded to IS. Characteristics of responders vs non-responders were: age 57.4 yrs (vs 57.6), 56% male (vs 51%), 39% White (vs 25%), 30% Hispanic/Latino (vs 30%), 17% Asian/Pacific Islander (vs 24%), 13% Black (vs 22%), mean eGFR 53 (vs 40 mL/min/1.73m²), serum albumin 2.7 (vs 2.9 g/dL), and median UPCR 5.8 (vs 5.3 g/g). Over median follow up of 2.5yrs, 88 patients (38%) progressed to ESKD of which 58pts were IS non-responders. Median time to ESKD was1.8 yrs. Median age at ESKD was 69 yrs. ESKD HR (95% CI) was 0.45 (0.28, 0.73) for IS responders vs non responders. Asian/Pacific Islanders (HR 2.01 [1.05, 3.83]) had the highest risk for ESKD.

Conclusion

We observed a high rate of ESKD within a relatively short time among primary FSGS pts treated with IS. IS non-responders compared to responders had over twice the risk for progression to ESKD.