Risk of clinical deterioration in patients with lupus nephritis receiving rituximab.

Rituximab is a chimeric anti-CD20 monoclonal antibody that is used as an immunosuppressive agent in cyclophosphamide refractory lupus nephritis to induce remission. Although uncontrolled case series suggest efficacy, this is not yet supported by evidence from prospective randomized controlled trials. The objective of this retrospective case series is to report the clinical outcome of seven patients who received rituximab for lupus nephritis in a single centre between 2011 and 2014. One patient had clinical evidence of an uncomplicated response to therapy. A second patient responded well with the first rituximab course, but had transient worsening of renal function and nephrotic syndrome with a second course. The other five patients all had evidence of a clinical deterioration following rituximab. Two had transient worsening of both renal function and nephrotic syndrome, with subsequent evidence of response in one of these. A fifth patient showed evidence of worsening nephrotic syndrome and renal function which then improved but with renal function remaining below the level present before rituximab. A sixth developed rapidly progressive renal failure following rituximab with active nephritis on renal biopsy and required rescue therapy with high dose steroids and cyclophosphamide. A seventh developed a transient worsening of her nephrotic syndrome and an exacerbation of extrarenal symptoms following rituximab. The two patients showing a good response had complete B cell depletion and incomplete depletion may be a factor in the deterioration seen in the other patients. Our experience suggests that rituximab therapy in lupus nephritis is not without risk and patients should be informed of this beforehand. This is particularly important in view of the uncertainty that rituximab will offer a therapeutic benefit.