Pathophysiology of moderate to severe plaque psoriasis: anti-IL-17 towards disease modification.

Psoriasis is a chronic inflammatory disease that can be triggered by injury, trauma, infection and medications. Genetic and immunologic studies have highlighted the importance of the interleukin (IL)-23/T-helper 17 (Th17) pathway in systemic psoriasis pathogenesis. Main IL-23 is an upstream regulatory cytokine with direct effects on epidermal keratinocytes and other resident skin cells while IL-17, a downstream molecule, can activate inflammatory responses in different cells across a diversity of organs. Disease modification could be achieved with drugs that can slow down the biological processes that cause the persistent inflammation in moderate to severe psoriasis. Early intervention with anti-IL-17 and anti-IL-23 agents in new-onset moderate to severe plaque psoriasis might modify the natural course of the disease. Perhaps we are not simply seeing a pharmacologic and mechanistic effect of new-generation biologics but eventually a disease modification process. In this short report we underline the main available data which supports an important role for IL-17 blockade and address whether these new drugs targeting the IL-23/IL-17 axis could be disease-modifying agents in plaque psoriasis. This type of data gains more relevance in the current pandemic era, where chronic patients undergoing earlier treatment may have better outcomes and consequently avoid constant hospital visits.