Biologics in SLE: the current status

Systemic lupus erythematosus (SLE) can be a severe and potentially life-threatening disease that often represents a therapeutic challenge because of its heterogeneous organ manifestations. Only glucocorticoids, hydroxychloroquine, mycophenolate mofetil, azathioprine, cyclophosphamide, and very recently belimumab have been approved for SLE therapy. Dependence on glucocorticoids and resistance to the approved therapeutic agents, as well as substantial toxicity, are frequent. B-cells abnormalities leading to autoantibody production play a central role in Systemic Lupus Erythematosus (SLE) pathogenesis. The targets of these biological therapies are directed toward the B cell depletion, interference in the co-stimulation signals and the blockade of cytokines. Biologic agents targeting specific pathways (i.e. T-B lymphocyte interaction, cytokines and complement) have been also proposed as new tools for SLE treatment. B-cell targeted therapies, including anti-B lymphocyte stimulator (BLyS) and anti-CD20 monoclonal antibodies are at forefront of new SLE treatment. Results from randomized trials in systemic lupus erythematosus (SLE) have been very disappointing, with lack of efficacy for some drugs and development of severe side-effects such as infections for others. Fortunately, as more and more trials of biologics in the treatment of lupus are being performed, the first promising results have been achieved. Today, belimumab is expected to become the first approved drug for use in lupus in several decades. In this review we will focus on biological drugs whose potential efficacy have been evaluated in open-label and randomized clinical trials. Biologics provide encouraging results that represent a possible option in the treatment of refractory lupus. Thus we review recent clinical trials in patients with systemic lupus erythematosus (SLE), with emphasis on outcomes and on mechanisms by which the biological agents suppress autoimmunity.