Many research groups have studied the pathogenesis of psoriasis by focusing on various compartments of the skin since the foundation of the European Society for Dermatological Research. Knowledge about the pathogenesis of psoriasis has grown into a branching model of innate and acquired immunity. Summary about the genetics of psoriasis has proved to be compatible with this model. Encouraged by these insights, pathogenesis-based treatments have appeared with remarkable efficacy and sustainability. 

The cytokine network carries major treatment targets for biologics with TNF-α, the IL-17 family, IL-23 and, in the case of generalized pustular psoriasis, IL-36. Furthermore, the Jak TYK2, PDE-4, and AHR are now known prey for new small molecules in the treatment of psoriasis. Psoriasis research is an example of best of a kind translational medicine, leading to pathogenesis-based treatments. 

Biologics for the treatment of psoriasis are:

• Anti-TNF-α: Etanercept, Adalimumab, Infliximab, Certolizumab
• Anti-IL-17: Anti-IL-17 A -Secukinumab, Ixekizumab; Anti-IL-17A/F -Bimekizumab; Anti-IL-17 receptor -Brodalumab
• Anti-IL-12/23 (p40 chain): Ustekinumab
• Anti-IL-23 (p19 chain): Risankizumab, Guselkumab, Tildrakizumab 

Small molecules for the treatment of psoriasis are: 

• Phosphodiesterase inhibitors:Apremilast systemic, Roflumilast topical
• TYK2 inhibitors: Deucravacitinib systemic, PF-06826647 systemic, Brepocitinib systemic
• Aryl hydrocarbon receptor agonist: Tapinarof

Source: van de Kerkhof PC. From empirical to pathogenesis-based treatments for psoriasis. J Invest Dermatol. 2022 Mar 3:S0022-202X(22)00082-3.