Background: For patients (pts) with PsA, several disease activity measures are available including very low/minimal disease activity (VLDA/MDA), cutoffs based on the Disease Activity in PsA (DAPSA) score, and on the Psoriatic Arthritis Disease Activity Score (PASDAS) score.

Objectives: To assess the rates of pts achieving these remission or low disease activity (LDA) criteria at Wk 24 using data from the SELECT-PsA 1 and SELECT-PsA 2 phase 3 studies;1,2 Additionally, we assessed the distribution of individual MDA components among pts who did or did not achieve MDA criteria at Wk 24.

Methods: In SELECT-PsA 1 and SELECT-PsA 2, pts with PsA and prior inadequate response (IR) or intolerance to ≥1 non-biologic DMARD (N=1705) or ≥1 biologic DMARD (N=642), respectively, were randomized to once daily upadacitinib (UPA) 15mg, UPA 30mg, adalimumab (ADA) 40mg every other week (SELECT-PsA 1 only), or placebo (PBO). Remission and LDA were assessed using VLDA/MDA, DAPSA scores of ≤4/≤14, and PASDAS scores of ≤1.9/≤3.2, at Wk 24 (Table 1). Non-responder imputation (NRI) was used for handling missing data; pts rescued at Wk 16 were considered non-responders. Pairwise comparisons between UPA doses and PBO or ADA were conducted using the Cochran-Mantel-Haenszel test.

Results: Overall, 2345 pts were analyzed; mean age 51 years, 53% female. In both studies, higher rates of remission and LDA were observed with both UPA doses vs PBO at Wk 24 (nominal P-values <0.05 for both time points; Table 1). Generally, higher rates of remission and LDA were also observed with UPA30 vs ADA in non-biologic DMARD-IR pts (nominal P-values <0.05). Greater rates of MDA/VLDA were observed at Wk 24 with UPA15 and UPA30 vs PBO in both studies and with UPA30 vs ADA in non-biologic DMARD-IR pts (nominal P-values <0.05 for all comparisons). The proportion of responder or non-responder pts receiving UPA15 or UPA30 was similar for each of the MDA components in both studies. At Wk 24, more responder and non-responder pts in both studies achieved Swollen Joint Count (SJC) 66 ≤1, Psoriasis Area and Severity Index (PASI) ≤1 or Body Surface Area-Psoriasis (BSA-Ps) ≤3%, and Leeds Enthesitis Index (LEI) ≤1 (Figure 1). Conversely, the proportion of pts Achieving Tender Joint Count (TJC) 68 ≤1 and Pt’s Global Assessment of Pain ≤1.5 tended to be lower.

Conclusion: Regardless of previous biologic DMARD failure, pts treated with UPA15 or UPA30 achieved a higher rate of remission or LDA measured by various disease activity measures vs PBO at Wk 24; higher rates of response were observed in most of the remission and LDA measures with UPA30 vs ADA in non-biologic DMARD-IR pts. Among pts who did or did not achieve MDA criteria at Wk 24, a greater proportion of UPA-treated pts achieved physician derived measures such as SJC ≤1, PASI ≤1 or BSA-Ps ≤3%, and LEI ≤1.