IL-23 Inhibitors: Guselkumab, Risankizumab, Tildrakizumab

Overview / Definition IL-23 inhibitors are a class of biologic medications designed to target and inhibit the activity of interleukin-23 (IL-23), a cytokine involved in inflammatory processes related to autoimmune diseases, particularly psoriasis. These agents include Guselkumab, Risankizumab, and Tildrakizumab, each demonstrating efficacy in managing moderate to severe plaque psoriasis. Epidemiology Psoriasis is a common chronic inflammatory skin condition affecting approximately 2-3% of the global population. Moderate to severe forms of the disease significantly impact patients' quality of life and are often resistant to conventional systemic therapies. The introduction of IL-23 inhibitors has provided new treatment options for these patients. Pathophysiology / Mechanism IL-23 is a key cytokine in the pathogenesis of psoriasis, promoting the differentiation and survival of T helper 17 (Th17) cells, which in turn produce pro-inflammatory cytokines such as IL-17 and IL-22. By selectively inhibiting IL-23, these biologics disrupt this inflammatory cascade, leading to: Reduction in keratinocyte proliferation Decreased inflammatory cell infiltration in the skin Improvement in clinical symptoms and skin clearance Clinical Presentation Patients with moderate to severe plaque psoriasis typically present with: Red, scaly plaques that may be itchy or painful Lesions commonly located on the elbows, knees, scalp, and lower back Associated comorbidities, including psoriatic arthritis, metabolic syndrome, and cardiovascular disease Diagnosis / Workup The diagnosis of psoriasis is primarily clinical, based on the characteristic appearance of the skin lesions. Key steps in the workup include: Patient history to assess severity and impact on quality of life Physical examination to evaluate the extent and morphology of skin lesions Consideration of a skin biopsy in atypical cases to rule out other conditions Treatment / Management IL-23 inhibitors have changed the treatment landsca