Exploration of the Cellular and Molecular Mechanisms in Patients Receiving Biotherapies Targeting the IL-23/IL-17 Axis in Cutaneous Psoriasis

Who May Qualify: All patients: - Adults (\>18 years) - Presenting with cutaneous psoriasis - Patients have signed an willing to sign a consent form - 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 Who May Qualify: 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 Always talk to your doctor about whether this trial is right for you.