Does Combination Therapy Increase Infection Risk in PsA?

TOPLINE:

Among adults with a diagnosis of psoriatic arthritis (PsA), those on combination targeted therapy did not have a significantly increased risk for serious bacterial infection or opportunistic infection compared with those on standard therapy.

METHODOLOGY:

• Researchers used IBM MarketScan data from 2015 to 2024 to identify adult patients with PsA, focusing on those who received combination targeted therapy and the risk for infections in these patients.
• Patients on combination targeted therapy were those with 3, 4, or 6 consecutive months of overlapping medication data for two or more biologics or targeted synthetic disease-modifying antirheumatic drugs. The standard therapy cohort included patients with similar medication data for any PsA-related drug classes.
• Among 82,399 patients with PsA, 53,025 had at least 3 consecutive months of data for any PsA medication, with 542 receiving combination targeted therapy (median age, 52.5 years; 62.9% women). The standard therapy group had 38,901 patients, and the combination therapy group had 200 patients (median age, 55.0 years; 57.0% women) with at least 6 months of medication data.
• Further, 2:1 propensity score matching was used to balance cohorts for analysis.
• Endpoints included all events of serious bacterial infection or opportunistic infection that resulted in hospital admission.

TAKEAWAY:

• The most common combination therapies included TNF inhibitors with apremilast and an interleukin-17 inhibitor with apremilast.
• In patients with PsA receiving combination targeted therapy for 3, 4, and 6 months, risks for serious infection were 7.38, 7.92, and 15.00 per 1000 patients, respectively, whereas risks for opportunistic infection were 1.85, 0, and 0 per 1000 patients, respectively.
• No significant difference in the risk for serious infection was found between the combination and standard therapy groups in an adjusted analysis and after propensity score matching.
• Similarly, the risk for opportunistic infection did not significantly differ between groups in an adjusted analysis and after propensity score matching.

IN PRACTICE:

“[Combination targeted therapy] most commonly included a biologic therapy and apremilast and had a similar infection risk as standard therapy,” the authors wrote.

SOURCE:

The study was led by Alexander Wu, of the University of Texas Southwestern Medical Center in Dallas. It was published online on August 20, 2025, in JAMA Dermatology.

LIMITATIONS:

The cohort size for combination targeted therapy was small. Most therapies included apremilast, which may not represent other combinations. Combination therapy with other immunosuppressive agents such as corticosteroids were not evaluated. The data source lacked comprehensive clinical information, potentially missing uninsured medication use.

DISCLOSURES:

This study received partial funding support from the Psoriasis and Psoriatic Arthritis Multicenter Advancement Network. Some authors disclosed receiving personal fees and/or grants from multiple pharmaceutical companies including Takeda, Pfizer, Novartis, UCB, and others, unrelated to this work.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.