Serum Dupilumab levels fail to reveal treatment response in Atopic Dermatitis at 16 weeks

Using the Eczema Area and Severity Index (EASI) disease severity of AD was assessed at baseline and weeks 16 and 52. Response to treatment was defined as the percent reduction in EASI score vs the baseline score and as an absolute EASI cutoff score of 7 or lower (controlled AD). Adverse effects were recorded during the first year. At 16 weeks, dupilumab serum levels and treatment responses were measured and analyzed. Multivariate logistic regression modeling was used to determine the prediction of response (EASI 90; EASI ≤7) and adverse effects at 52 weeks, with serum dupilumab levels at 16 weeks in the presence of the covariates age and sex.

Results: 

• Among the total of 295 patients with a mean [SD] age, of 41.5 [15.9] years, there were 170 [57.6%] men.
• The median drug level was 86.6 μg/mL at 16 weeks of treatment.
• There were no significant differences in serum dupilumab levels between responder statuses (EASI, <50, 50, 75, or 90) at week 16.
• Nonsignificant odds ratios (ORs) were observed for serum dupilumab levels at 16 weeks regarding the prediction of long-term response and adverse effects in Multivariate logistic regression analysis. 

The study results show no association between serum dupilumab levels at week 16 and treatment response and adverse effects. Target availability of the interleukin-4 receptor subunit α may have an interpatient variability producing heterogeneity in response. 

Further reading: Spekhorst LS, de Graaf M, Loeff F, et al. Association of Serum Dupilumab Levels at 16 Weeks With Treatment Response and Adverse Effects in Patients With Atopic Dermatitis: A Prospective Clinical Cohort Study From the BioDay Registry. JAMA Dermatol. Published online November 02, 2022. doi:10.1001/jamadermatol.2022.4639