Z NG1,3, V SASONGKO2,3, S MAY3, M PANAT3
1St George Hospital, Kogarah, Australia, 2St Vincent’s Hospital, Sydney, Australia, 3Tamworth Rural Referral Hospital, Tamworth, Australia
Background: Rituximab, a monoclonal anti-CD20 antibody is currently the third-line therapy of frequently relapsing or resistant minimal change disease. Recent pediatric case series has proposed the use of a novel humanized anti-CD20 antibody ofatumumab, reporting superior efficacy due to its ability to bind a membrane-proximal epitope, and dissociates from its target at a slower rate compared to rituximab.
Case report: We describe a case of a 23-year-old male with biopsy-proven relapsing steroid-resistant minimal change disease. He has previously failed steroid and calcineurin inhibitor therapy, requiring rituximab therapy to sustain a 2-year period of remission prior to this relapse.Patient received a treatment protocol of six weekly infusions of ofatumumab (300mg for 1st week, then 2000mg weekly for 5 weeks) with a standard premedication regime. Our patient was followed up weekly in the infusion clinic with serum albumin, serum creatinine, urine albumin:creatinine ratio and body weight observed at T=0 weeks, T=3 weeks and T=6 weeks.A significant reduction in albuminuria was achieved (spot urine albumin reduced from 2190mg/L to 81mg/L, urine albumin/creatinine ratio 267.1mg/mmol to 7.4mg/mmol), with an improvement in serum albumin from 8g/L to 25g/L and improvement in clinical fluid status (89kg to 65kg) by the end of 6 weeks. His serum creatinine level improved from 166mmol/l to 68mmol/l. Our patient currently remain in remission. Ofatumumab was well tolerated throughout the 6 weeks, with the exception of one mild infusion related side effect noted on induction.
Conclusions: Ofatumumab is an effective alternative to rituximab in managing steroid/calcineurin resistant nephrotic syndrome and may confer long-term disease remission benefit over rituximab.
Jolene (Zhuo Lin) Ng is a current Basic Physician Trainee at the St George – Sutherland Basic Physician Trainee Network in New South Wales.