Innovative Uses of Tumor Necrosis Factor α Inhibitors

Tumor necrosis factor alpha (TNF-alpha) is an inflammatory cytokine that is released by a variety of cell types, including immune effector cells and tissue-specific cells. TNF-alpha has been shown to promote inflammation via the activation and induction of cytokines interleukin 1 (IL-1), IL-6, and IL-8 and by the upregulation of adhesion molecules on endothelial cells leading to increased leukocyte extravasation. Theoretically, the blockade of TNF should have widespread potential in the treatment of numerous inflammatory diseases. Currently, 3 TNF-alpha inhibitors available in the United States are approved for psoriasis and psoriatic arthritis: infliximab, etanercept, and adalimumab. Numerous case reports and case series have been published in recent years reporting the off-label uses of these drugs in various inflammatory skin diseases. This review summarizes the most recent reports on 20 such conditions.