PASI 100 Response Rates in Moderate to Severe Psoriasis: a Systematic Literature Review and Analysis of Clinical Practice Guidelines

Background: Response to treatments in psoriasis can be assessed using the PASI response 50, 75, 90 or 100. Achieving a PASI 100 response would mean a complete resolution of the patient's basal lesions. Therefore, PASI 100 score has been increasingly used in the context of research, but its role in daily practice is currently controversial.

Objective: (1) To analyze PASI 100 response rates to pharmacological treatments; (2) To examine clinical practice guidelines (CPGs) recommendations/comments on PASI 100.

Methods: We conducted a systematic literature review (SLR). Selection criteria concerned patients with psoriasis, reporting PASI 100.

Results: Overall, 65 studies were included. Patients on methotrexate achieved at 16 weeks a PASI 100 of 7.3%. For TNF inhibitors rates were: 3.7-11.1% at 12 weeks, 13.7-20% at 16 weeks, 10.7-24% at 24 weeks and 21.8-34.8% at 1 year. IL-17 inhibitors achieved 23.3-44% at 12 weeks, 44.3-57.2% at 16 weeks, 39.7-67.5% at 24 weeks and 41.4-67.5% at 1 year. And the reported by IL-12/23 inhibitors were 12%/23.8% at 12 weeks, 32.7%/50% at 16 weeks, 44% at 24 weeks and 41.8%/56.3% at 1 year. PASI 100 response is scarcely commented in the CPGs.

Conclusions: PASI 100 response rate is an endpoint fundamentally restricted to research.