HDAC IIa composes of HDAC4, HDAC5, HDAC7, and HDAC9, numbers of studies demonstrated HDAC IIa inhibition as an alternative approach to avoid the progression of various diseases, examples like breast tumors (18), pancreatic cancer (19), multiple myeloma (20), and type 2 diabetes (21). Here, HDAC9 is linked to AL amyloidosis.