NCS 613

NCS 613 is a small molecule drug acting as a potent, selective inhibitor of *phosphodiesterase type 4* (PDE4), with highest selectivity for the PDE4C subtype (IC50 ≈ 1.4 nM)[3][5]. Its mechanism leads to increased intracellular cyclic AMP (cAMP), which suppresses systemic and local inflammation. NCS 613 has demonstrated anti-inflammatory and anti-proliferative effects in models of systemic lupus erythematosus (SLE), lupus nephritis, and human lung adenocarcinoma. It inhibits the phosphorylation of p38 MAPK and prevents nuclear translocation of NF-κB, thereby decreasing proinflammatory cytokines such as TNFα, IL-6, and IL-8. In preclinical models, NCS 613 delayed renal disease progression and improved survival in lupus-prone mice, suggesting potential therapeutic use in SLE and related chronic inflammatory diseases.