Synta Pharmaceuticals has announced that the first patients have been dosed in two separate Phase IIa clinical studies of its lead immunomodulatory compound, apilimod mesylate (STA-5326), in rheumatoid arthritis (RA) and common variable immunodeficiency (CVID).

Apilimod mesylate is a novel, oral, small-molecule compound that selectively inhibits the production of the IL-12 protein family, which includes the cytokines IL-12 and IL-23, important regulators of the immune response implicated in major chronic inflammatory diseases, including Crohn's disease, RA, psoriasis and multiple sclerosis. The IL-12 family has also been shown to be a critical factor in the pathogenesis of the gastrointestinal (GI) complications of CVID.