Belimumab: a BLyS-specific inhibitor for the treatment of systemic lupus erythematosus.

Belimumab (Benlysta), which recently received marketing approval, is the first of a new class of immunomodulators with a novel mechanism of action. It is a specific inhibitor of the soluble B-lymphocyte stimulator (BLyS) cytokine, which has been implicated in the pathogenesis of systemic lupus erythematosus (SLE). Two large phase III randomized controlled clinical trials evaluated the safety and efficacy of belimumab combined with standard therapy and showed that the efficacy of this treatment was significantly superior to placebo plus standard therapy. Belimumab is an evidence-based therapeutic option for patients with general lupus disease activity and may signal a shift in the existing treatment paradigm from therapeutic selection targeting specific organ involvement to an approach directed at tackling multisystem disease activity and preventing the disease from worsening.