title: Targeting BAFF and APRIL in systemic lupus erythematosus and other antibody-associated diseases.
abstract: The B cell-stimulating molecules, BAFF (B cell activating factor) and APRIL (a proliferation-inducing ligand), are critical factors in the maintenance of the B cell pool and humoral immunity. In addition, BAFF and APRIL are involved in the pathogenesis of a number of human autoimmune diseases, with elevated levels of these cytokines detected in the sera of patients with systemic lupus erythematosus (SLE), IgA nephropathy, Sjögren's syndrome, and rheumatoid arthritis. As such, both molecules are rational targets for new therapies in B cell-driven autoimmune diseases, and several inhibitors of BAFF or BAFF and APRIL together have been investigated in clinical trials. These include the BAFF/APRIL dual inhibitor, atacicept, and the BAFF inhibitor, belimumab, which is approved as an add-on therapy for patients with active SLE. Post hoc analyses of these trials indicate that baseline serum levels of BAFF and BAFF/APRIL correlate with treatment response to belimumab and atacicept, respectively, suggesting a role for the two molecules as predictive biomarkers. It will, however, be important to refine future testing to identify active forms of BAFF and APRIL in the circulation, as well as to distinguish between homotrimer and heteromer configurations. In this review, we discuss the rationale for dual BAFF/APRIL inhibition versus single BAFF inhibition in autoimmune disease, by focusing on the similarities and differences between the physiological and pathogenic roles of the two molecules. A summary of the preclinical and clinical data currently available is also presented.
authors.affiliation: a EMD Serono Research & Development Institute, Inc. , Billerica , Massachusetts , USA.
authors.forename: Eileen
authors.initials: E
authors.lastname: Samy
authors.affiliation: a EMD Serono Research & Development Institute, Inc. , Billerica , Massachusetts , USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Wax
authors.affiliation: b Institute for Advanced Biosciences , University Grenoble Alpes , INSERM U1209, Grenoble , France.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Huard
authors.affiliation: c Merck KGaA , Darmstadt , Germany.
authors.forename: Henry
authors.initials: H
authors.lastname: Hess
authors.affiliation: d Department of Biochemistry , University of Lausanne , Lausanne , Switzerland.
authors.forename: Pascal
authors.initials: P
authors.lastname: Schneider
mesh_terms: D000818:Animals; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D001323:Autoantibodies / Q000378:metabolism; D053264:B-Cell Activating Factor / Q000378:metabolism*; D001402:B-Lymphocytes / Q000276:immunology*; D002986:Clinical Trials as Topic; D006801:Humans; D007167:Immunotherapy / Q000379:methods*; D008180:Lupus Erythematosus, Systemic / Q000188:drug therapy*; D058990:Molecular Targeted Therapy; D011993:Recombinant Fusion Proteins / Q000627:therapeutic use; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13 / Q000378:metabolism*
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D001323:Autoantibodies; D053264:B-Cell Activating Factor; D011993:Recombinant Fusion Proteins; C505719:TNFSF13B protein, human; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13; C511911:belimumab; C524618:TACI receptor-IgG Fc fragment fusion protein
keywords: APRIL; BAFF; SLE; TACI-Ig; autoimmune disease