Apremilast is a pharmaceutical substance with the chemical name N-[2-[1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl]-1,3-dioxoisoindolin-4-yl]acetamide. Its CAS number is 608141-41-9.

Apremilast is a small molecule inhibitor of phosphodiesterase 4 (PDE4), an enzyme that plays a role in the regulation of inflammation. It is primarily used as a treatment for certain autoimmune diseases, such as psoriasis and psoriatic arthritis.

The substance works by inhibiting the production of certain pro-inflammatory mediators, such as tumor necrosis factor-alpha (TNF-a), interleukin-17 (IL-17), and interleukin-23 (IL-23). By reducing the levels of these mediators, it helps to suppress the autoimmune response and alleviate symptoms associated with chronic inflammation.

Apremilast is available in oral tablet form and is usually taken once or twice daily, as prescribed by a healthcare professional. It may take several weeks for the full therapeutic effects to be observed.

As with any medication, apremilast may caus