It works by inhibiting the enzyme phosphodiesterase 4 (PDE4), which is involved in the regulation of inflammatory and immune responses. By inhibiting PDE4, apremilast reduces the production of certain pro-inflammatory cytokines and increases the production of certain anti-inflammatory cytokines, thus suppressing inflammation.
Apremilast was approved by the US Food and Drug Administration (FDA) in 2014 under the brand name Otezla, and is currently marketed by Celgene Corporation (a subsidiary of Bristol Myers Squibb).