Tocilizumab in systemic lupus erythematosus: data on safety, preliminary efficacy, and impact on circulating plasma cells from an open-label phase I dosage-escalation study.

Objective: To assess the safety of interleukin-6 receptor inhibition and to collect preliminary data on the clinical and immunologic efficacy of tocilizumab in patients with systemic lupus erythematosus (SLE).

Methods: In an open-label phase I dosage-escalation study, 16 patients with mild-to-moderate disease activity were assigned to receive 1 of 3 doses of tocilizumab given intravenously every other week for 12 weeks (total of 7 infusions): 2 mg/kg in 4 patients, 4 mg/kg in 6 patients, or 8 mg/kg in 6 patients. Patients were then monitored for an additional 8 weeks.