Specific Biologics Linked to Fewer Infections in Older Adults with Psoriasis, PsA

Biologic treatments for psoriasis and psoriatic arthritis (PsA) that target interleukin (IL)-12, IL-23, or IL-17 are associated with lower serious infection rates among older adults with these psoriatic diseases, according to new findings.1

These data suggest the potential safety benefits of these biologics for older adults who are known to be at higher risk of infection. The findings were the result of a new analysis conducted to estimate any links between various systemic medications for psoriatic conditions with rates of serious infection among adults in the 66 years and older age bracket.

The study was conducted by a team of investigators such as Aaron M. Drucker, MD, ScM, from the Department of Medicine at the University of Toronto in Canada. Drucker et al. highlighted that systemic drugs for psoriatic diseases had already been known to impact patients’ immune systems and potentially raise infection risk, though they further noted mixed data in prior research into such risks in older adults.2

“The objective of this study was to estimate the association of different systemic treatments for psoriasis and psoriatic arthritis with the rate of serious infection among older adults,” Drucker and colleagues wrote. “We made an a priori hypothesis that biologics would be associated with increased rates of serious infection.”1

Analyzing Infection Risk in Older Adults with Psoriatic Disease

The investigators conducted their analysis using a cohort study design, implementing health data from the Ontario area routinely collected at the population level. Their sources were linked through unique encoded identifiers assigned to individual residents and then assessed at ICES, known formerly as the Institute for Clinical Evaluative Sciences.

In Ontario, coverage of visits with clinicians and hospitalizations are universal through the Ontario Health Insurance Plan (OHIP). The investigative team of this study gathered their hospitalization data from the Canadian Institute for Health Information Discharge Abstract Database, and they sourced their records of visits with clinicians from the OHIP database.

Records on prescriptions for medications reimbursed by the provincial public drug program were extracted by the team using the Ontario Drug Benefit (ODB) database’s records. The team’s use of patients’ data was given authorization under section 45 of Ontario’s Personal Health Information Protection Act. It was also approved by the ICES Privacy and Legal Office.

The team carried out their analysis of data between November 2021 - August 2024. In terms of the study population, the analysis involved Ontario residents who were aged 66 years and older with psoriasis or PsA who were prescribed their first systemic medication between April 2002 - December 2020.

The investigators evaluated the use of systemics as a time-varying exposure, deciding to classify them into 5 categories: (1) methotrexate, (2) other conventional systemic drugs, (3) anti-tumor necrosis factor (anti-TNF) biologic therapies, (4) other biologics designed to target IL-12, IL-23, or IL-17, and (5) tofacitinib.

In their analysis, they determined the primary outcome evaluated would be time to serious infection. For the purposes of assessing any associations between systemic treatment categories and serious risk of infection, the research team used multivariable Andersen-Gill recurrent event regression analysis.

There were 11,641 individuals in total who had been newly prescribed with systemic drugs, with the median age of these patients being 71 and 53% being reported as female. The investigative team highlighted reports of 1,967 serious infections over a median follow-up duration of 4.8 years. The team further highlighted rates of incidence serious infection per 100 person-years in each treatment category as the following:

• Methotrexate: 2.7
• Other older systemic drugs: 2.5
• Anti-TNF biologic drugs: 2.2
• Other biologic drugs (IL-12, IL-23, IL-17 inhibitors): 1.4
• Tofacitinib: 8.9

Methotrexate (RR, 0.95 [95% CI, 0.85-1.07]), other conventional systemic therapies (RR, 0.92 [95% CI, 0.79-1.07]), and anti-TNF biologics (RR, 0.87 [95% CI, 0.69-1.10]) were not shown in the team’s multivariable-adjusted model to be significantly linked to a risk increase for serious infection versus non-use periods.1

However, the analysis did demonstrate that other biologic use (RR, 0.65 [95% CI, 0.48-0.88]) was shown to have an association with a diminished risk of serious infection among the study subjects. Tofacitinib, however, was associated with a significantly higher risk (RR, 2.89 [95% CI, 1.14-7.34]).

“Our study suggests safety benefits of newer biologics and, among people with psoriatic arthritis, safety benefits of anti-TNF biologics, which could be used to inform updates to formulary rules,” they wrote.1

References

1. Drucker AM, Sutradhar R, Ling V, et al. Systemic Therapies for Psoriatic Disease and Serious Infections in Older Adults. JAMA Dermatol. Published online March 19, 2025. doi:10.1001/jamadermatol.2025.0144.

2. Schneeweiss MC, Perez Chada L, Gottlieb AB, Merola JF. Older adults on systemic treatment for psoriasis and risk of infection: a propensity score-matched population-based study. Br J Dermatol. 2020;183(3):564-566. doi:10.1111/bjd.19028.