Panobinostat is an oral deacetylace (DAC) inhibitor approved on February 23, 2015 by the FDA for the treatment of multiple myeloma. The approval was accelerated based on progression-free survival, therefore confirmatory trials by the sponsor to demonstrate clinical efficacy in multiple myeloma treatment are in progress of being conducted. Panobinostat is marketed by Novartis under the brand name Farydak. Panobinostat is a deacetylase (DAC) inhibitor. DACs, also known as histone DACs (HDAC), are responsible for regulating the acetylation of about 1750 proteins in the body; their functions are involved in many biological processes including DNA replication and repair, chromatin remodelling, transcription of genes, progression of the cell-cycle, protein degradation and cytoskeletal reorganization. In multiple myeloma, there is an overexpression of DAC proteins. Panobinostat inhibits class I (HDACs 1, 2, 3, 8), class II (HDACs 4, 5, 6, 7, 9, 10) and class IV (HDAC 11) proteins. Panobinostat's antitumor activity is believed to be attributed to epigenetic modulation of gene expression and inhibition of protein metabolism. Panobinostat also exhibits cytotoxic synergy with bortezomib, a proteasome inhibitor concurrently used in treatment of multiple myeloma.