A 4-year observation in lupus nephritis patients treated with an intensified B-lymphocyte depletion without immunosuppressive maintenance treatment-Clinical response compared to literature and immunological re-assessment

Abstract

Background: B cells (BC) play a critical role in systemic lupus erythematosus (SLE). BC depletion therapy still remains an attractive option, despite the disappointing results of randomized controlled trials (RTCs).

Methods: Twelve patients with SLE [3 males, mean age 43.8 yrs (25-55)] with severe multiorgan involvement all including kidney (3 patients with Class IV, 4 with Class III/V and 5 with Class V, according to the International Society of Nephrology/Renal Pathology Society glomerulonephritis classification), skin lesions [10], severe polyarthralgias with arthritis [10], polyserositis [2], and lymphadenopathy [5] have been prospectively treated with an intensified B cell depletion therapy (IBCDT) protocol due to their resistance or intolerance to previous therapy (six cases) or as a front line immunosuppressive treatment in 6 women with unsatisfactory therapeutic compliance or as a specific request of a short-time immunosuppression for gestational perspectives.

Protocol: Rituximab (RTX) 375 mg/sm on days 1, 8, 15, 22, and 2 more doses after 1 and 2 months, associated with 2 IV administrations of 10mg/kg of cyclophosphamide and 3 methylprednisolone pulses (15mg/kg) followed by oral prednisone (0.8 mg/kg/day, rapidly tapered to 5mg/day by the end of the 3rd month after RTX). No further immunosuppressive maintenance therapy has been given.

Results: Patients had been followed-up for a mean of 44.5 (24-93)months. Significant decreases (p<0.05) were found in the levels of ESR (baseline mean value: 55.0mm; 3 months: 36; end of follow-up: 13), anti-dsDNA antibodies (baseline: 185 U; 3 months: 107; end of follow-up: 15), and proteinuria (baseline: 4.9 g/24h; 3 months: 0.97; end of follow-up: 0.22). C4 values (baseline 11 mg/dl) significantly increased (p<0.05) after 3 months (22 mg/dl) and at the end of the follow-up (20mg/dl). Of the 12 patients, 9 (75%) have remained well after one cycle of IBCDT, with no flare (mean 51.6 months [25-93]). Three patients relapsed after 36, 41, and 72 months, respectively. Following re-treatment, they again showed complete remission over 18-48 months of observation.

Conclusions: A promising role of RTX in an intensified protocol of induction therapy can be envisaged in patients for whom avoiding immunosuppressive maintenance therapy and sparing steroids are particularly appealing. Moreover, our data confirm in one of the longest follow-up available, the opportunity to reconsider the regimens of BL depletion in the treatment of the most severe or refractory forms of SLE despite the disappointing results of RCTs.