Antibiotic Exposure: A Concern for Biologic Therapy Persistence in Psoriasis

A nationwide French cohort study published in JAMA Dermatology found that systemic antibiotic exposure is associated with reduced persistence of biologic therapies in patients with psoriasis, with evidence of a dose-dependent relationship.

The investigators analyzed longitudinal data from 36,129 adults in the French National Health Insurance database who initiated their first biologic therapy for psoriasis between 2012 and 2022, with follow-up extending through 2024. The primary endpoint was biologic persistence, defined as time to discontinuation or switch of the index biologic. Antibiotic exposure was assessed both at baseline, during the six months prior to biologic initiation, and longitudinally during follow-up.

Overall, approximately 26% of patients received systemic antibiotics before starting biologic therapy, and 61% were exposed during follow-up. Multivariable analyses showed that antibiotic exposure in the six months preceding biologic initiation was associated with a higher risk of biologic discontinuation. This association increased with the number of antibiotic dispensations, indicating a dose-response relationship, with higher discontinuation risk observed among patients receiving multiple antibiotic courses.

The most commonly prescribed antibiotic classes in the cohort were β-lactams, macrolides, and fluoroquinolones. Subgroup analyses across different biologic classes yielded consistent findings, supporting the robustness of the observed association. The authors noted that alterations in the gut microbiota may contribute to impaired immune-modulating effects of biologic therapies and could represent a potential explanation for the observed reduction in treatment persistence. However, they emphasized that the observational design and the possibility of unmeasured confounding limit causal interpretation.

In summary, systemic antibiotic exposure was associated with reduced biologic therapy persistence in patients with psoriasis, with a dose-dependent increase in discontinuation risk. The findings highlight the need for further studies to clarify causality and to better understand the mechanisms underlying this association.

Key Takeaways:

• Antibiotic exposure is associated with reduced biologic persistence in psoriasis.
• Multiple antibiotic courses are linked to greater discontinuation risk.
• Consider antibiotic history before starting biologics and monitor for early loss of response.