IL-23 and IL-17 Inhibitors Linked to Lower Risk of Psoriatic Arthritis in Patients with Plaque Psoriasis

A retrospective observational study, published in Annals of the Rheumatic Disease, has found that patients with plaque psoriasis (PsO) treated with IL-17 or IL-23 inhibitors have a lower risk of developing psoriatic arthritis (PsA) compared to those receiving tumor necrosis factor (TNF) inhibitors. These findings may have implications for treatment selection in patients with PsO without joint involvement but at risk for progression.

The study analyzed 622 bionaïve patients with PsO initiating biologic therapy. Patients were treated with either TNF inhibitors (n=317), IL-17 inhibitors (n=164), or IL-23 inhibitors (n=141). The cohort was followed over 2510 person-years, averaging 4.1 years per patient. Incident PsA developed in 60 patients (10%) during follow up: 45 (14.2%) in the TNF group, 9 (5.5%) in the IL-17 group, and 6 (4.3%) in the IL-23 group.

To account for baseline differences across treatment groups, the investigators used inverse probability of treatment weighting. After adjustment, the risk of developing PsA was significantly lower for patients on IL-23 inhibitors compared to those on TNF inhibitors, with a hazard ratio (HR) of 0.57 (95% CI, 0.34–0.96). IL-17 inhibitors also showed a reduced risk, though this finding did not reach statistical significance (HR 0.63; 95% CI, 0.38–1.05).

“The HRs of PsA were 0.63 for IL-17 and 0.57 for IL-23 compared with the TNF treatment group,” the authors reported, noting a consistent trend toward reduced PsA development among patients receiving IL-17 and IL-23 inhibition.

This study is among the few to directly compare PsA risk across biologic classes in bionaïve patients with PsO without prior joint disease. The lower incidence of PsA in the IL-17 and IL-23 groups suggests a potential disease-modifying effect on PsA prevention, though further prospective studies are needed to confirm this possibility.

“The risk of developing PsA appeared slightly different in patients receiving diverse classes of biologics,” the authors concluded.

For dermatologists treating patients with PsO, these findings highlight the potential value of biologic class selection based not only on skin clearance but also on prevention of joint disease. In patients at increased risk for PsA, IL-23 or IL-17 inhibitors may offer added benefit in mitigating progression to joint involvement.

Reference
Gisondi P, Bellinato F, Galeone C, et al. Risk of developing psoriatic arthritis in patients with psoriasis initiating treatment with different classes of biologics. Ann Rheum Dis. 2025;84(3):435-441. doi:10.1016/j.ard.2025.01.006