To target or not to target APRIL in systemic lupus erythematosus: that is the question!
Among the cytokines that regulate B cell homeostasis are the TNF-like ligands BLyS (B lymphocyte stimulator, also called BAFF for B cell activation factor) and APRIL (a proliferation inducing ligand). BLyS and APRIL share two receptors, i.e.
BCMA (B-cell maturation antigen) and TACI (transmembrane activator and CAML interactor). Therapeutic approaches using biologics are limited for treatment of lupus patients.
One previously approved drug is belimumab that antagonizes the B cell stimulator BLyS. Another biologic inhibiting BLyS and APRIL -atacicept- was terminated for serious adverse events raising the question whether APRIL should be neutralized in auto-immunes diseases.