An immunosuppressive drug that inhibits DHODH (IC50s = 0.134, 1.29, and 10.6 μM for human, rat, and mouse isoforms, respectively); inhibits the proliferation of T cells and B cells and the secretion of IL-17 (IC50s = 12.9, 3.7, and 6.0 μM, respectively, in human cells)