Updates on B-cell immunotherapies for systemic lupus erythematosus and Sjogren's syndrome

Abstract

Last year was marked by important clinical and mechanistic studies that improved our understanding of B-cell immunotherapy for systemic lupus erythematosus (SLE) and Sjogren's syndrome. Here, we will highlight the most relevant studies published in the last 18 months. The highlight of the year was the approval of belimumab on the basis of two major trials. On the flip side, the disappointing results of rituximab in lupus nephritis provided a clinical and mechanistic counterpoint in SLE. Still, major limitations in the LUpus Nephritis Assessment with Rituximab (LUNAR) trial, positive subset analysis and new open studies and registries continue to provide hope for and major insights into the use of B-cell depletion. In Sjogren's syndrome, the role of B-cell depletion has been further investigated, both for glandular and extraglandular manifestations of the disease with mixed results in a disease in which outcomes are notoriously hard to measure. The approval of anti-B cell activating factor therapy and an increasing body of open studies with rituximab as well as subset studies and secondary analysis of the Efficacy and Safety of Rituximab in Moderately-to-Severely Active Systemic Lupus Erythematosus (EXPLORER) and LUNAR trials provide hope for B-cell immunotherapy and significant insight into its mechanisms of action and utilization in a selected subset of patients. Ongoing clinical trials of other B-cell targeting agents are eagerly anticipated.