SP0143\u2005CASE 1 DISCUSSANT: HOW IS TACKLING OLIGO-ARTICULAR DISEASE DIFFERENT FROM POLYARTHRITIS? CAN WE USE TRIAL RESULTS FROM POLY-ARTICULAR PSA IN A PATIENT WITH MONO/OLIGO-ARTHRITIS?

Abstract

Background: Oligoarthritis is a well recognised phenotype in psoriatic arthritis (PsA) where less than 5 joints are involved with active arthritis. In cohort studies, the proportion of patients presenting with mono/oligoarthritis varies from 20-70% depending on the timeframe studied and duration of disease. However most studies of therapeutic agents in PsA have focused on polyarticular disease. Although the majority of studies accept a minimum of 3 active joints for inclusion, the average tender and swollen joint counts are usually over 10 at baseline. Objectives: To review data supporting treatment of psoriatic mono/oligoarthritis including comparisons of response rates in therapeutic trials in PsA and the differential performance of outcome measures in this subtypes of disease. Results: When considering the applicability of RCT data to mono/oligoarthritis in PsA it is important to address the populations included in these studies. Nearly all large therapeutic studies exclude monoarthritis, and while some oligoarthritis patients are eligible for inclusion in most RCTs, the demographics of the population included suggest that this is a minority. Unfortunately most clinical trials have not reported the efficacy results separately for oligoarthritis and polyarthritis patients. The other key consideration is that the outcome measures used in the majority of trials are developed and validated on patients with polyarticular PsA. Thus assessing effectiveness of therapies may be limited in the oligoarthritis population as the response measures are less sensitive to change. Conclusion: Although data from polyarticular RCT populations is often used to choose therapies in oligoarticular PsA, there is a real paucity of data to ensure that we are treating these patients optimally. Future research is needed to address the variable prognosis seen in mono/oligoarticular PsA, to ensure that appropriate outcome measures are used to test different therapies and to provide clear evidence on the efficacy of drugs in this important subtype of disease. Disclosure of Interests: Laura C Coates Grant/research support from: AbbVie, Celgene, Lilly, Novartis and Pfizer, Consultant for: AbbVie, Amgen, BMS, Celgene, Galapagos, Gilead Sciences Inc., Janssen, Lilly, Novartis, Pfizer, Prothena Corp and UCB