Differential joint-level response to secukinumab in psoriatic arthritis: A collaborative European observational...

To investigate possible variations in treatment response to secukinumab at distinct anatomic joint locations in patients with psoriatic arthritis (PsA) in routine clinical care.

Patients with PsA monitored in 9 registries contributing to the European Spondyloarthritis Research Collaboration Network were included in this study if at least 1 joint from the 28-joint count was clinically swollen at the start of treatment with secukinumab. The primary outcome was time to first resolution of clinical joint swelling at each joint location, excluding the shoulder, during a follow-up of 2 years. Estimated hazard ratios (HRs) for resolution between different joint locations were compared with interval-censored mixed-effects transformation models adjusted for age, sex, and previous biologic/targeted synthetic disease-modifying antirheumatic drug (DMARD).

A total of 590 patients with 2794 swollen joints at the initiation of secukinumab were included (mean [SD] age 51.7 [12.3] years, 54% female patients, 77% co-treatment with conventional synthetic DMARDs). Compared with the wrist, the elbow had a higher rate of resolution of joint swelling (HR = 1.75, 95% CI = 1.10-2.79). The metacarpophalangeal joints (MCP) 4 and 5 (HR = 2.01, 95% CI = 1.40-2.88 and HR = 1.98, 95% CI = 1.28-3.06, respectively), as well as most proximal interphalangeal joints (PIP), except PIP3, had a higher rate of resolution compared with the wrist. No significant difference in the resolution of joint swelling was found for the wrist compared with MCP2, MCP3, PIP3, and the knee.

In PsA, the time to resolution of joint swelling after initiation of secukinumab differs between distinct joint locations.