ARTICLE | Translation in Brief

IL-17A's autoimmune dichotomy

Why blocking IL-17A has differing effects in Crohn's and psoriasis

December 3, 2015 8:00 AM UTC

A pair of studies has resolved the conundrum of why blocking IL-17A helps in psoriasis but exacerbates Crohn's disease, and highlights the dangers of assuming that hitting a target in autoimmunity will have the same outcome, regardless of indication. The findings suggest the different pathologies of seemingly similar autoimmune diseases make targeting general mechanisms riskier than companies may have bargained for.

In two papers published in Immunity, groups from Amgen Inc. (NASDAQ:AMGN) and Merck & Co. Inc. (NYSE:MRK) uncovered disease mechanisms that help explain why therapeutics targeting interleukin-17A (IL-17A) signaling - once thought to be a mechanism at the root of many disorders - is effective in psoriasis but has the opposite effect in Crohn's disease. ...