Abstract
OBJECTIVE: Evaluate relationship between radiographic progression and clinical outcomes in post hoc analyses of patients with psoriatic arthritis (PsA) receiving up to 2 years of guselkumab therapy in the phase 3, placebo-controlled, randomised trial, DISCOVER-2. METHODS: Biologic-naïve adults with active PsA (≥5 swollen joints /≥5 tender joints ; C reactive protein ≥0.6 mg/dL) were randomised to guselkumab 100 mg every 4 weeks (Q4W); guselkumab 100 mg at week 0, week 4, then every 8 weeks (Q8W); or placebo→guselkumab 100 mg Q4W (week 24). Radiographs (hands/feet) at week 0, week 24, week 52 and week 100 were scored via PsA-modified van der Heijde-Sharp (vdH-S) methodology. In these post hoc analyses, mean changes in vdH-S scores were summarised according to achievement of American College of Rheumatology 20/50/70 response; low disease activity (LDA) defined by Disease Activity in Psoriatic Arthritis (DAPSA) ≤14 or Psoriatic ArthritiS Disease Activity Score (PASDAS) ≤3.2, or minimal/very low disease activity (MDA/VLDA); and normalised physical function (Health Assessment Questionnaire-Disability Index (HAQ-DI) ≤0.5). Response rates for achieving MDA/VLDA and each component were determined among patients with and without radiographic progression (change in total vdH-S score >0.5). No formal hypothesis testing was performed. RESULTS: 664 of 739 treated patients in DISCOVER-2 continued study treatment at week 52 and were included in these analyses. Mean changes in vdH-S scores from weeks 0 to 100 among all patients in the Q4W and Q8W groups were 1.7 and 1.5, respectively. Among all guselkumab-randomised patients, those who achieved ACR20/50/70, DAPSA LDA, PASDAS LDA, MDA, VLDA and HAQ-DI ≤0.5 (normalised physical function) had smaller mean changes in vdH-S scores than did non-responders at week 52 (0.2-1.2 vs 1.7-4.1) and week 100 (0.3-1.2 vs 2.0-4.6). Relative to patients with radiographic progression, those without progression were more likely to achieve the MDA criteria related to swollen and tender joint counts, patient-reported pain and global assessment, and normalised physical function through week 100. CONCLUSION: In these post hoc analyses, the achievement of low levels of disease activity, including MDA, was associated with diminished rates of radiographic progression observed in patients receiving up to 2 years of guselkumab. Radiographic non-progressors were more likely to achieve patient-reported MDA criteria of minimal pain and normalised physical function compared with radiographic non-responders. TRIAL REGISTRATION NUMBER: NCT03158285.