Inclusion Criteria:  All patients:  Adults (>18 years) Presenting with cutaneous psoriasis Patients have signed an informed consent Beneficiary of the health insurance, except for the AME Only for patients of Group 1 Patients require systemic treatment for psoriasis Patients are naïve to biological therapies  Only for patients of Group 2:  Patients requiring treatment with anti-IL-23 biologics (guselkumab, risankizumab, tildrakizumab) upon referent physician's decision. Patients are naïve to biological therapies or have received only one biologic, with a "wash-out" period of at least 4 months  Non inclusion Criteria:  For all :  Patient is minor Patient is pregnant or breastfeeding Patient is immunocompromised Patient is under legal protection, curatorship, guardianship Patient refuses consent Patient is unable to comply with study requirements for geographic, social or psychiatric reason. Beneficiary of the AME Only for patients of Group 1 Patient has received biologics Only for patients of Group 2 Patient has a contraindication to the chosen biotherapy Patient has received biologics within the last 4 months Patient has been treated with 2 or more biologics Patient has already received an anti-IL-23 biologic