Ofatumumab: A Therapeutic Option for Secondary Membranous Nephropathy in Adults
- Glomerular Diseases: Case Reports
November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Trials
- Shah, Monarch, University of Virginia, Charlottesville, Virginia, United States
- Kunaprayoon, Lalida, University of Virginia, Charlottesville, Virginia, United States
- Cavanaugh, Corey J., University of Virginia, Charlottesville, Virginia, United States
B-cell targeting therapies like cyclophosphamide and rituximab are integral in treating many glomerulopathies like FSGS, lupus nephritis, and high-risk membranous nephropathy (MN). Newer B cell targeting therapies like ofatumumab has infrequently been used in MN, although trials are ongoing. Much less is known about their use in secondary MN. We describe the use of ofatumumab in two cases of secondary MN.
We retrospectively analyzed two cases of MN treated with ofatumumab. The first case was a 53-year-old woman with nephrotic syndrome and a history of biopsy-proven MN with kappa predominance staining on immunofluorescence and a co-occurring MGUS (IgG Kappa) with a B-cell lymphocytosis with a kappa restricted B-cell. She was thus diagnosed with monoclonal gammopathy of renal significance and treated with 3 cycles of Cyclophosphamide after insurance denied her rituximab. Unfortunately, she relapsed 1 year later and was treated with ofatumumab, 300mg day 1, and 700mg day 14. Her proteinuria responded from 3.32g to 0.44 grams proteinuria 2 months after infusion. Case 2 was a 48-year-old female with profound nephrotic syndrome (56g/24-hour urine collection, serum albumin 1g/dL) refractory to cyclophosphamide combined with steroids and rituximab. She then developed anaphylaxis to rituximab on subsequent infusions and was switched to ofatumumab. She received 100 mg on day 1, 700mg on day 21, and 700 mg on day 35 for cycle 1, then 300 mg weekly for 1 month on cycle two (6 months after cycle 1). Patient 1 saw complete renal remission and patient 2 had a partial response with a reduction from 10.8 grams proteinuria to 3.6 g pr/cr ratio with normalization of serum albumin.
This case series has shown that ofatumumab is a viable option for patients with secondary MN. The novel anti-CD20 monoclonal antibody like ofatumumab can become another option for patients who have refractory disease despite completing historical therapies like rituximab and cyclophosphamide. It also provides an agent for patients who have allergies to rituximab. More options for novel B-cell targeting therapies should be explored for secondary MN. Future clinical trials would be helpful to establish its efficacy and safety profile.