Guselkumab yields durable benefit in biologic-naïve PsA patients

The interleukin (IL)-23p19-subunit inhibitor guselkumab appears to produce improvements in multiple disease domains of psoriatic arthritis (PsA) with no unexpected safety findings through 2 years of treatment in biologic-naïve patients, according to the phase III DISCOVER-2 trial.

DISCOVER-2 included 739 patients with active PsA (≥5 swollen and ≥5 tender joints; C-reactive protein [CRP] ≥0.6 mg/dL) despite prior nonbiologic therapy. They were randomized to receive guselkumab 100 mg every 4 weeks; or at week 0, week 4, and every 8 weeks thereafter; or placebo. Those on placebo were switched to guselkumab every 4 weeks starting at week 24.

Efficacy outcomes included ≥20 percent/50 percent/70 percent improvement in the American College of Rheumatology (ACR) components (ACR20/50/70), complete skin clearance (assessed using the Investigator’s Global Assessment of psoriasis score [IGA] of 0), enthesitis (Leeds Enthesitis Index) and dactylitis (Dactylitis Severity Score) resolution, and changes in PsA-modified van der Heijde-Sharp (vdH-S) radiographic scores.

At week 100, all treatment groups showed improvements in arthritis signs/symptoms and extra-articular manifestations, including ACR20 (68–76 percent), ACR50 (48–56 percent), ACR70 (30–36 percent), and IGA=0 (55–67 percent) responses, and enthesitis (62–70 percent) and dactylitis (72–83 percent) resolution rates.

Furthermore, the rates of radiographic progression remained low through week 100 (mean changes in PsA-modified vdH-S scores from weeks 52–100, 0.13–0.75).