Targeted therapy seems untargeted: TNF-α antagonists in psoriasis as an example

Biologic therapies have emerged as targeted treatments in psoriasis, offering personalized options for patients. However, when examining the cytokine network in psoriasis, this raises the question of whether biologics should be viewed as targeted therapies. This article reviews the literature focusing on the impact of tumor necrosis factor (TNF)-α antagonists on the cytokine profile and immunocytes in psoriasis. The literature suggests that the effects of TNF-α antagonists extend beyond TNF-α. These agents have a significant influence on various cytokines of the innate and adaptive immune system, including interferon-γ, interleukin (IL)-1, IL-4, IL-6, IL-8, IL-12, IL-17, IL-22, IL-23, and IL-24 in blood and skin. In addition, TNF-α antagonists also affect immunocyte counts, such as neutrophil elastase-positive cells. This demonstrates that, even though biologic treatments were initially designed to target specific molecules structurally, their function should not be narrowly considered targeted. This concept has important implications in clinical practice, including for the understanding and knowledgeable prediction of drug-related side effects, such as colitis, inflammatory bowel disease, myocarditis, and infections, as well as for taking necessary precautions before prescribing medications.