Abstract: TH-PO158

Continuous B Cell Depletion for Resistant, Steroid Dependent, and Relapsing Nephrotic Syndrome in Adults

Session Information

Category: Glomerular

  • 1005 Clinical Glomerular Disorders

Authors

  • Cortazar, Frank B., MGH, Boston, Massachusetts, United States
  • Dunbar, Colleen B, MGH, Boston, Massachusetts, United States
  • Laliberte, Karen A., MGH, Boston, Massachusetts, United States
  • Niles, John, MGH, Boston, Massachusetts, United States
Background

The clinical course of minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) can be complicated by resistance to treatment, steroid dependence, and frequent relapses. Treatment options for such patients are limited. We present a retrospective series of patients with these phenotypes treated with rituximab (RTX)-induced continuous B cell depletion.

Methods

Patients were included if they had biopsy proven MCD or FSGS that was resistant, steroid dependent, or relapsing. All patients had a UPCR ≥ 3.5 g/g and were treated with RTX-induced continuous B cell depletion. Resistant disease was defined as failure to achieve a partial remission (PR) with prednisone at 1 mg/kg per day for 3 months or a calcineurin inhibitor or mycophenolate mofetil. Steroid dependence was defined as relapse during or within 2 weeks of steroid tapering. Relapsing disease was defined as at least two prior relapses. PR was defined as a urine protein:Cr ratio (UPCR) of ≤ 3.5 g/g and a 50% reduction from baseline, while CR was defined as a UPCR ≤ 0.3 g/g. Relapse after any remission was a UPCR ≥ 3.5 g/g.

Results

We identified 11 patients who met the inclusion criteria (Table). Over a median followup of 4.5 years (IQR, 2-5), patients received a median of 9 RTX doses (IQR, 8-15) and were in a state of B cell depletion for 3.7 years (IQR, 2-5). All patients entered PR at a median time of 89 (IQR, 34-144) days and 7 patients entered CR at a median of 362 (IQR, 34-1208) days. Prednisone dose was tapered from 60 mg/d (IQR, 15 to 60) at entry to 5 mg/d (IQR 0-7.5) at 1 year. Three patients sustained a relapse after PR, but all subsequently obtained a remission. No relapses occurred following CR.

Conclusion

Continuous B cell depletion is an effective treatment strategy for complicated cases of MCD and FSGS. Additional studies are needed.

CsA, cyclosporine, Cyc, cyclophosphamide; MMF, mycophenolate mofetil; Pred, prednisone; Tac, tacrolimus