AVN-944 (VX-944) is an orally active, potent, selective, noncompetitive and specific inhibitor of IMPDH (inosine monophosphate dehydrogenase). AVN-944 is an essential rate-limiting enzyme in de novo guanine nucleotide synthesis. AVN-944 is also an inhibitor of arenavirus RNA synthesis, and blocks arenavirus infection. AVN-944 has broad anti-cancer activities, and can be used for multiple myeloma (MM) and acute myeloid leukemia (AML) research[1][2][3].