Tasquinimod (ABR-215050) is an orally active small molecule with antiangiogenic and antitumor properties. It functions as an S100A9 inhibitor and binds the HDAC4 Zn domain with high affinity (Kd 10-30 nM). This agent has been investigated in preclinical in vivo models for cancers like prostate carcinoma and in vitro for immunomodulatory effects.