Clinical Report: Obesity and Early Biologic Treatment Failure in Psoriasis
Overview
In this retrospective cohort across five Italian dermatology centers, obesity was associated with a higher risk of primary biologic treatment failure in adults with plaque psoriasis. Primary failure occurred in 17.0% of treatment lines among patients with obesity versus 5.8% among those without obesity; the adjusted hazard ratio was 2.75 (95% CI 1.59–4.77). Obesity was not significantly associated with secondary failure or safety-related discontinuation.
Background
Psoriasis affects approximately 2–3% of the global population and biologic therapies targeting TNF-α, IL-17, and IL-23 have transformed treatment of moderate-to-severe disease. Drug survival—the time a patient remains on treatment—is used in routine practice to reflect effectiveness, safety, and acceptability. Obesity is prevalent among people with psoriasis and has been associated in prior analyses with lower biologic response and shorter treatment persistence, often due to ineffectiveness. This study examined whether obesity and increasing BMI were associated with specific reasons for biologic discontinuation and whether associations differed by therapeutic class.
Data Highlights
Measure
Finding
Primary failure, patients with obesity
17.0% of treatment lines
Primary failure, patients without obesity
5.8% of treatment lines
Obesity and primary failure after multivariable adjustment
HR 2.75 (95% CI 1.59–4.77)
BMI and primary failure
Higher BMI was associated with increased risk; each 5 kg/m² increment was associated with HR 1.37 (95% CI 1.14–1.65), as reported in the supplied web research context
Obesity and other discontinuation reasons
No significant association with secondary failure or safety-related discontinuation
Biologic classes among patients with obesity
TNF-α inhibitors had the highest primary failure rate; IL-17 and IL-23 pathway inhibitors had lower adjusted risks than TNF-α inhibitors
Key Findings
The retrospective study included adults with plaque psoriasis treated with biologics across five dermatology centers in Italy’s Veneto region; treatment lines, rather than patients, were the unit of time-to-event analysis.
Primary failure was reported in 17.0% of treatment lines among patients with obesity and 5.8% among those without obesity.
After multivariable adjustment, obesity remained associated with primary failure (HR 2.75, 95% CI 1.59–4.77).
Increasing BMI was associated with greater primary failure risk; the supplied web research context reports a 37% higher hazard per 5 kg/m² increase (HR 1.37, 95% CI 1.14–1.65).
Obesity was not significantly associated with secondary failure or discontinuation for safety reasons.
Among patients with obesity, TNF-α inhibitors had the highest primary failure rate, while IL-17 and IL-23 pathway inhibitors had lower adjusted risks than TNF-α inhibitors. Separately, a 2024 meta-analysis of 40 studies and 21,438 patients reported associations between higher BMI and lower biologic response, with heterogeneity and limited power for drug-specific subgroup analyses.
Clinical Implications
The cohort findings identify obesity and higher BMI as factors associated with primary biologic failure, rather than with secondary failure or safety-related discontinuation. The supplied EuroGuiDerm guidance frames comorbidities and individual patient factors as relevant to systemic therapy selection and monitoring; the cohort’s class-specific findings are observational and do not establish comparative treatment effects.
Conclusion
In this Italian real-world cohort, obesity was associated with increased primary biologic failure in psoriasis, with higher BMI also associated with greater risk. The association varied by therapeutic class, while no significant association was reported for secondary failure or safety-related discontinuation.
