OP0311 Notable evolutions in the characteristics of psoriatic arthritis clinical trials populations in the era of biological treatments
Authors: A.-S. Vandendorpe, K. De Vlam, R. Lories
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Psoriatic arthritis is a chronic inflammatory disease that affects the musculoskeletal system. It can include arthritis, spondylitis, dactylitis and enthesitis, and is strongly associated with the presence of psoriasis. The introduction of biological therapies as a treatment option has brought a significant improvement in disease control for these patients. <h3>Objectives</h3> In this study, we wanted to detect emerging differences in demographic and clinical characteristics of the PsA-patient study population since the introduction of biologicals. <h3>Methods</h3> We selected 12 phase II- and phase III-trials and divided them into 3 treatment periods based on different time windows and working mechanisms of the particular biologicals or targeted DMARDs. Published tables with the baseline demographic and clinical characteristics of study population from the individual studies were used. For inclusion of a specific parameter, it had to be present in at least one study of each period. An exception to this rule was made for the 'number of patients with prior anti-TNF therapy', only present in studies from the second and third period. Parameters were defined in different categories: patient characteristics (gender, age, race, weight), disease characteristics (duration of PsA, presence of dactylitis, presence of enthesitis, psoriasis body surface area), disease activity parameters (swollen joint count, tender joint count, C-reactive protein (CRP)-level, visual analogue scale of disease activity and pain, disease activity score, psoriasis area severity index (PASI)-score), disease effects (total Sharp score, health assessment questionnaire disability index (HAQ-DI)-score) and prior treatments. For the continuous data, we calculated a weighted mean and standard deviation (SD) per period. Data not available in the form of mean ±SD in the original studies were therefore not included. For the discrete data, we summed up the patients meeting the criterium from all the studies in a given period and calculated a percentage. We used the RStudio software. For the normally divided data, we used ANOVA-test for a group analysis to find significant differences between the time periods. For the discrete data, we used Chi-square test. <h3>Results</h3> Detailed analysis of the baseline characteristics showed some remarkable differences between the three different treatment periods with most data indicating that these shifts have occurred between the first and the second period. In comparison to the initial trials with etanercept, infliximab and adalimumab, gender and race show more diversity, patients are older but have a shorter disease duration, show lower swollen and tender joint counts, but more enthesitis, and have lower CRP-levels. Although several of these parameters suggest an overall lower disease activity in the second and third period of trials, this is not reflected in the physician's and patient's perspective of disease activity and the HAQ-DI score. <h3>Conclusions</h3> Our analysis found significant differences in patient characteristics, disease characteristics, disease activity, disease effects and use of prior treatments between the 3 periods of treatment drugs since the introduction of biologicals. Patients appear to be considered earlier and with less severe disease albeit that the subjective evaluation of disease activity goes in the opposite direction. <h3>Disclosure of Interest</h3> A.-S. Vandendorpe: None declared, K. De Vlam Consultant for: KDV reports speaker's and consultancy fees from Abbvie, Celgene, Johnson and Johnson, Merck, Novartis, Pfizer and UCB, R. Lories Grant/research support from: Leuven Research and Development, the technology transfer office of KU Leuven has received grant support on behalf of R.L. from Abbvie, Boehringer-Ingelheim, Celgene, Pfizer and UCB, Consultant for: Leuven Research and Development, the technology transfer office of KU Leuven has received speaker's and consultancy fees on behalf of R.L. from Abbvie, Boehringer-Ingelheim, Celgene, Janssen, Novartis, Merck, Pfizer and UCB