Continuous improvement through differential trajectories of individual minimal disease activity criteria with guselkumab in active psoriatic arthritis: post hoc analysis of a phase 3, randomized, double-blind, placebo-controlled study

Background: To explore the trajectory of, and factors contributing to, achievement of individual criteria of minimal disease activity (MDA) in patients with active psoriatic arthritis (PsA) treated with guselkumab. Methods: The Phase 3, randomized, placebo-controlled DISCOVER-2 study enrolled adults (N = 739) with active PsA despite standard therapies who were biologic/Janus kinase inhibitor-naive. Patients were randomized 1:1:1 to guselkumab 100 mg every 4 weeks; guselkumab 100 mg at week 0, week 4, then every 8 weeks; or placebo. In this post hoc analysis, patients randomized to guselkumab were included and pooled (N = 493). Longitudinal trajectories of achieving each MDA criterion through week 100 were derived using non-responder imputation. Time to achieve each criterion was estimated with Kaplan-Meier analysis. Multivariate regression for time to achieve each criterion (Cox regression) and achievement at week 100 (logistic regression) was used to identify contributing factors. Results: Continuous improvement across all MDA domains was shown over time. ~70% of patients achieved near remission in swollen joint count (SJC), Psoriasis Area and Severity Index (PASI), and enthesitis through week 100. Median times to achieve individual criteria differed significantly (p < 0.0001), with SJC ≤ 1 (20 weeks), PASI ≤ 1 (16 weeks), and ≤ 1 tender entheses (16 weeks) being faster than patient-reported criteria (pain ≤ 15 mm, patient global assessment of arthritis and psoriasis ≤ 20 mm, Health Assessment Questionnaire-Disability Index ≤ 0.5) and tender joint count ≤ 1. Higher baseline domain scores, older age, worse fatigue, and increased body mass index were significant predictors of longer time to achieve minimal levels of disease activity assessed via patient-reported criteria. Conclusions: Substantial proportions of guselkumab-treated patients achieved individual MDA criteria, each showing continuous improvement through week 100, although with distinct trajectories. Median times to achieve physician-assessed MDA ...