New Therapies for Psoriasis and Psoriatic Arthritis

Christopher T. Ritchlin; James G. Krueger


Curr Opin Rheumatol. 2016;28(3):204-210. 

In This Article

Outcome Measures in Psoriasis and Psoriatic Arthritis Clinical Trials

Outcome measures of the skin and joints that are commonly performed in clinical trials are summarized in the reference by Mease et al..[14] The PASI is a composite measure of erythema, scaling, and induration in different body parts. It is measured on a scale from 1 to 64 but commonly expressed as the percentage of patients who demonstrate a 50, 75, 90, or 100% (PASI 50, 75, 90 or 100) improvement following treatment. The primary arthritis endpoint is the percentage of patients meeting criteria for 20% improvement in the ACR20. Individual ACR components include the number or tender and swollen joints, patient's global assessment of disease activity, physician's global assessment of disease activity and responses on the Health Assessment Questionnaire-Disability Index (HAQ-DI). Secondary outcomes are often the ACR50 and 70. The change in enthesitis can be assessed with the Leeds Enthesitis Index and dactylitis by a simple count or the Leeds Dactylitis Index.