Response to treatment in psoriatic arthritis, the effect of age: analysis of patients receiving ustekinumab in the PsABio real-world study

Background This post-hoc analysis of PsABio (NCT02627768) evaluated safety, effectiveness and treatment persistence in patients < 60 and ≥ 60 years of age receiving ustekinumab over 3 years. Methods Measures included adverse events (AE), clinical Disease Activity Index for Psoriatic Arthritis (cDAPSA) low disease activity (LDA) including remission, Psoriatic Arthritis Impact of Disease-12 (PsAID-12), Minimal Disease Activity, dactylitis, nail/skin involvement and time to treatment stop. Data were analysed descriptively. Results Overall, 336 patients < 60 and 103 ≥ 60 years received ustekinumab, with a similar gender balance. A numerically lower proportion of younger patients reported at least one AE: 124/379 (32.7%) vs 47/115 (40.9%) for patients < 60 and ≥ 60 years, respectively. Serious AEs were low (< 10%) in both groups. At 6 months, the proportion of patients with cDAPSA LDA was 138/267 (51.7%) and 35/80 (43.8%) for patients < 60 and ≥ 60 years, respectively, with the effectiveness being maintained through 36 months. PsAID-12 mean scores reduced for both groups from a baseline mean of 5.73 and 5.61 for patients < 60 and ≥ 60 years, respectively, to 3.81 and 3.88, respectively, at 6 months, and 2.02 and 3.24, respectively, at 36 months. Regarding treatment persistence, 173/336 (51.5%) vs 47/103 (45.6%) patients < 60 and ≥ 60 years, respectively, stopped or switched treatment. Conclusion Fewer AEs were observed over 3 years for younger versus older patients with PsA. There were no clinically meaningful treatment response differences. Persistence was numerically higher in the older age group.