Abstract: SA-OR101
Felzartamab for IgA Nephropathy: Final Results of the IGNAZ Study
Session Information
- Late-Breaking Science Orals - 2
October 26, 2024 | Location: Room 6C, Convention Center
Abstract Time: 05:10 PM - 05:20 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Barratt, Jonathan, University of Leicester, Leicester, United Kingdom
- Floege, Jürgen, RWTH Aachen University, Aachen, Germany
- Lafayette, Richard A., Stanford Medicine, Palo Alto, California, United States
- Schwartz, Brian M., Human Immunology Biosciences, Inc., a Biogen Company, South San Francisco, California, United States
- Patel, Uptal D., Human Immunology Biosciences, Inc., a Biogen Company, South San Francisco, California, United States
- Manser, Paul, Human Immunology Biosciences, Inc., a Biogen Company, South San Francisco, California, United States
- Kivman, Lisa, Human Immunology Biosciences, Inc., a Biogen Company, South San Francisco, California, United States
- Haertle, Stefan, MorphoSys AG, Planegg, Bayern, Germany
- Faulhaber, Nicola, MorphoSys AG, Planegg, Bayern, Germany
- Thakur, Anjali G., MorphoSys AG, Planegg, Bayern, Germany
- Barbour, Sean, The University of British Columbia Faculty of Medicine, Vancouver, British Columbia, Canada
Background
Felzartamab is a monoclonal antibody that binds to CD38 on plasma cells–the likely source of pathogenic Gd-IgA1 and autoantibodies in IgA nephropathy (IgAN). The randomized, double-blind, placebo-controlled phase 2a IGNAZ study assessed the efficacy and safety of felzartamab vs placebo (PBO) in patients with IgAN. Final 24-month data are reported.
Methods
Patients aged 18−80 years with biopsy-confirmed IgAN, proteinuria ≥1.0 g/d (≥0.5 g/d for Japanese patients), and eGFR ≥30 mL/min per 1.73m2 using renin-angiotensin inhibitors ≥3 months were randomized 1:1:1:1 in Part 1 to PBO (n=12) or felzartamab in 1 of 3 arms: 2 doses in 15 days (M1; n=12), 5 doses in 2 months (M2; n=11), and 9 doses in 5 months (M3; n=13). In Part 2, 6 Japanese patients received open-label M3.
Results
Patients were 67% men, with a mean age of 41.6 years, UPCR of 1.7 g/g, and eGFR of 74.6 mL/min per 1.73m2. In Part 1, 40/48 patients completed treatment. Treatment with felzartamab led to rapid, clinically meaningful reductions in UPCR vs PBO, with the greatest effect in the M3 arm (Fig A). Mean eGFR declined less in the felzartamab arms vs PBO (Fig B). Among felzartamab arms, IgA reductions were rapid and durable (lasting 19 months after the last dose); IgG recovered by 6−9 months. Efficacy in Part 2 was similar to that of the Part 1 M3 arm. Treatment-emergent AEs were typically grade 1 or 2 and were not dose-dependent. The most common treatment-related AE was infusion-related reaction (IRR), usually on dose one. There was one treatment-related serious AE of IRR. Five patients discontinued felzartamab for IRR/hypersensitivity. The infection incidence was similar across felzartamab arms; all were grade 1 or 2 and non-serious.
Conclusion
Felzartamab was generally well tolerated and led to sustained proteinuria reduction and reduced eGFR decline vs PBO, indicating potential disease modification in patients with IgAN. Investigation of felzartamab in patients at high risk for loss of kidney function is warranted.
Funding
- Commercial Support – Human Immunology Biosciences, Inc., a Biogen Company