Drug survival and effectiveness of ustekinumab in patients with psoriatic arthritis. Real-life data from the biologic Apulian registry (BIOPURE)

This study aims to evaluate the drug survival and effectiveness of ustekinumab in psoriatic arthritis (PsA) patients naïve to biologics or inadequate responders to tumor necrosis factor (TNF-IR) inhibitors in real life. PsA patients starting ustekinumab were enrolled from 2014 to 2016. Joint involvement, peripheral or axial, Psoriatic Area Severity Index, Disease Activity Psoriatic Arthritis (DAPSA), Lee Enthesitis Index, Health Assessment Questionnaire, body mass index, comorbidities, co-therapies, mechanism of action, and causes of discontinuation of prior TNFi were collected at baseline, and 6 and 12 months. Twelve-month drug survival was evaluated by Kaplan-Meier curves. Hazard ratios (HRs) of drug discontinuation adjusted for baseline factors were estimated by multiple Cox regression analysis. Percentages of DAPSA-based remission, as crude value and adjusted for drug retention (LUNDEX index), were compared by χ2 test. Mean differences of DAPSA from baseline to 6 and 12 months were compared between naïve and TNF-IR patients by ANOVA. Of 160 PsA patients starting ustekinumab, 54 were naïve and 106 were TNF-IR. Twelve-month drug survival was significantly higher in naïve (87%) than in TNF-IR (68%, p = 0.01). Baseline co-therapy with methotrexate did not increase the persistence on ustekinumab. Naïve patients had the lowest risk of ustekinumab discontinuation (HR 0.27, p = 0.01), and the highest DAPSA-based remission (34%, LUNDEX 26%). Mean differences from baseline of DAPSA was significantly greater in naïve than in TNF-IR patients at 12 months (- 14.4 ± 10 vs. - 4.1 ± 17, p = 0.01). Our data showed that ustekinumab has a good effectiveness in real life and the best outcomes are achieved in biologic-naïve PsA patients.