KZR-504 is a highly selective inhibitor of immunoproteasome low molecular mass polypeptide 2 (LMP2) , with IC 50 s of 51 nM, 4.274 μM for LMP2 and LMP7, respectively. KZR-504 is of interest for the treatment of autoimmune disease In Vivo Evaluating the inhibition of LMP2, and antitargets LMP7 and β5, in mouse tissues reveals that KZR-504 (compound 12) is both selective and potent in vivo with >50% target inhibition achieved at >1 mg/kg in all tissues tested except brain . MCE has not independently confirmed the accuracy of these methods. They are for reference only. Form:Solid IC50& Target:IC50: 51 nM (LMP2), 4.274 μM (LMP7)