Early Intervention in Plaque Psoriasis: is Bimekizumab Able to Delay Chronic Inflammation?

Inclusion Criteria: 1. Men and women 2. ≥ 18 and \<45 years 3. Plaque psoriasis without psoriatic arthritis 4. Patients with mild psoriasis PASI \>2 and \<6 5. Patient with at least one lesion on the elbows, or the knees, or the lower back to be recorded as target lesion (additional lesions in other areas on top are allowed) 6. Disease duration less than 6 months (short duration psoriasis) or \>2 years (long duration psoriasis) 7. The psoriasis lesions should not having being treated by any topical treatment for at least 2 weeks 8. For women of childbearing potential, an effective contraception (estroprogestative pill, contraceptive implant, IUD, condoms or tubal ligation) should be used for more than one month before the inclusion in the study. A urine pregnancy test (βHCG in urines) will be performed. Thus, a woman who is permanently sterile and therefore unable to procreate should not be subjected to pregnancy tests. Women who are sexually abstinent are not requested to use a contraception. However, they must agree to take one if they want to become sexually active. 9. Affiliation to a social security system 10. Signed informed consent 11. Patient willing and able to attend all study visits Exclusion Criteria: 1. Pregnant or breast-feeding women. Or women who plan to get pregnant during the study duration. 2. Concomitant use of topical or systemic immunosuppressive medication or steroids in the past 12 weeks 3. Personal history of skin cancer 4. Personal history of cancer of less than 5 years 5. Patients with active infection 6. Abnormal blood counts (neutrophils \<1500/mm3 and platelets \<150 000/mm3) and/or positive HIV, HVB and HVC testing at screening. 7. Patients with personal history of keloid scars 8. Patients with personal history of hypersentitivity to xylocaine and/or adrenalin 9. Vulnerable people: minors, adult under guardianship or deprived of freedom 10. Participants in other clinical therapeutic studies involving a drug that could interfere with the present evaluation