CD40LG and systemic lupus erythematosus: Treatment of patients with moderately to severely active SLE with epratuzumab led to reductions in the levels of CD22, with the number of B cells in the peripheral blood decreasing by ∼30–40% and IgM levels reducing by 20%. However, treatment with epratuzumab in conjunction with standard therapy did not improve efficacy outcomes at week 48 compared to treatment with placebo in conjunction with standard treatment.