ONX 0912 is an orally bioavailable proteasome inhibitor. It potently targets the chymotrypsin-like activity of the 20S proteasome subunits β5 and LMP7 (IC50s = 36 and 82 nM, respectively). ONX 0912 inhibits the growth of multiple myeloma cells at nanomolar concentrations while not decreasing the viability of normal peripheral blood mononuclear cells at 1 μM. It blocks the growth of xenografted human multiple myeloma cells in mice when given orally. ONX 0912 has potential applications in certain types of cancer as well as other diseases that require proteasome activity.
