Apremilast (CC-10004) (CC-10004) is a potent and orally active PDE4 (IC50=74 nM) with anti-inflammation activities.

PDE4:74 nM

Apremilast inhibits TNF-α release by lipopolysaccharide (LPS) with an IC50 of 104 nM (pIC50=6.98±0.2), which almost exactly replicates previous reported TNF-α inhibition by Apremilast on peripheral blood mononuclear cells (PBMCs) (IC50=110 nM) and which is similar to the potency of Apremilast for PDE4 enzymatic inhibition (IC50=74 nM). These results are clearly consistent with the hypothesis that Apremilast inhibits TNF-α by increasing intracellular cAMP levels. PKA, Epac1 and Epac2 knockdowns prevented TNF-α inhibition and IL-10 stimulation by Apremilast[1].

Apremilast is solubilized in DMSO and stored, and then diluted with appropriate media (DMSO 0.025%) before use[1]. Raw 264.7 cells (100,000) are grown in 96-well plates. After 24 h, cells are stimulated with vehicle (final concentration of 0.025% DMSO) or with Apremilast at the indicated concentrations. After 30 minutes cells are stimulated with LPS 1 μg/mL for 4 h. When studying CGS21680 , SCH58261, ZM241385, BAY60-6583, or GS6201, the adenosine receptor ligands are added 15 minutes before Apremilast. Methotrexate is added 24 h and 1 h before Apremilast. Supernates are then collected and TNF-α levels are quantified with the Mouse TNF-α Quantikine ELISA Kit. IC50 (EC50) calculations are made using non-linear regression, sigmoidal dose-response, constraining the top to 100 % and bottom to 0 %, allowing variable slope, using GraphPad Prism v6.00[1].