Biologic therapies targeting IL‑17 and IL‑23 have revolutionized psoriasis management, enabling rapid and durable disease control. Yet treatment selection still follows a trial‑and‑error approach, and clinically validated biomarkers for personalization remain absent. To outline current challenges in biomarker development for psoriasis and describe the design and aims of the PICASSO prospective cohort as a platform for future personalized medicine. Despite evidence that IL‑17/IL‑23 inhibitors may induce disease modification through effects on effector, memory, and regulatory immune cells, reliable predictive or prognostic biomarkers have not emerged. Barriers include complex pathogenesis, universally high biologic efficacy reducing need for stratification, inconsistent findings from genetic or transcriptomic studies, and the multifactorial nature of comorbidities. PICASSO is a 10‑year prospective biobank/registry enrolling patients within three years of disease onset. Biological samples are longitudinally linked to clinical and epidemiological data, with follow‑ups every 2.5 years. The ultimate aim is to identify biomarkers predicting disease trajectory. Personalized psoriasis care requires biomarkers predicting progression and comorbidity risk. PICASSO represents a step toward disease‑modifying, preventive precision medicine.
