Anti-CD20 therapy in patients with refractory systemic lupus erythematosus: a longitudinal analysis of 52 Hispanic patients.

The objective of this study was to investigate the efficacy and safety of anti-CD20 treatment in Hispanic patients with refractory systemic lupus erythematosus and to determine whether baseline parameters predict disease flare. Fifty-two patients with systemic lupus erythematosus, 13 with active lupus nephritis, eight with thrombocytopenia, three with leukocytopenia, 25 with severe musculoskeletal involvement and three with skin involvement) refractory to conventional therapy were treated with anti-CD20 treatment (rituximab; MabThera, Roche) plus ongoing immunosuppressive treatment. Disease activity was assessed monthly using the SLEDAI validated for the Mexican population with a follow-up period of 6 months. At 6 months of follow-up, significant clinical improvements were detected, with a reduction in the global SLEDAI validated for the Mexican population score. Five of the 13 patients with lupus nephritis (38.4%) had a complete renal response and five (38.4%) had a partial response. Rituximab was also effective in patients with autoimmune thrombocytopenia, inducing a significant increase in platelet counts (p = 0.012). Nineteen of 25 patients with severe musculoskeletal involvement had remission of arthritis. Only one of the three patients with skin involvement had no lesions at 6 months. Rituximab treatment also allowed a reduction of the oral prednisone dose in the majority of patients. No baseline predictors of flare were found. Treatment was discontinued after the first infusion in two patients due to serum sickness and in another due to pulmonary infection. In conclusion, the addition of rituximab to conventional immunosuppressive therapy may be an effective strategy for lupus nephritis, autoimmune thrombocytopenia and inflammatory polyarthritis in patients with refractory systemic lupus erythematosus.