The development of litifilimab (BIIB 059) for cutaneous and systemic lupus erythematosus.

This review describes the litifilimab (BIIB 059) development program to date for systemic lupus erythematosus (SLE) and cutaneous lupus erythematosus (CLE). Plasmacytoid dendritic cells (pDCs), major producers of type I interferons (IFN-I), play a key role in SLE pathogenesis. Litifilimab, a humanized monoclonal antibody, binds to BDCA2, a protein uniquely expressed on pDCs. The consequence of BDCA2 ligation is the inhibition of IFN-I as well as IFN-III, cytokine and chemokine production. Phase I and II LILAC trial parts A and B achieved primary end points in SLE and CLE patients, confirming the importance of pDCs and IFN-I in SLE and CLE. Litifilimab is currently being evaluated in phase III trials in both SLE and CLE.