Evolution of Blood Eosinophilia in Patients with Severe Asthma Treated with Dupilumab

Dupilumab is a monoclonal antibody used for the treatment of patients with uncontrolled severe asthma (SA) and elevated T2 markers. The development of eosinophilia (EOS) is a common adverse event in patients with SA treated with Dupilumab. However, therapy response does not appear to be associated with this occurrence. The objective of this study was to monitor blood eosinophils in a cohort of patients treated with Dupilumab. A prospective observational study was conducted on patients with SA who initiated Dupilumab and completed at least 6 months of therapy. Response variables, such as the Asthma Control Test (ACT), systemic glucocorticoid (CS) dose, number of exacerbations, and pre-bronchodilator FEV1, were recorded. EOS was assessed before treatment and at week 12, 24, and 52. 28 patients were included, with a median age of 59.5 [IQR: 49.5-64.0], 60% female. The distribution of clinical-demographic variables is presented in Table 1. Figure 1 (A) shows median [IQR] EOS throughout the observation period. There were no cases of hypereosinophilia >5000 cells/μL, however 50% of patients developed EOS >500 cells/μL by week 24, with a median of 460 [200-1290]cél/μL. The use of Dupilumab led to clinical improvement assessed by ACT, reduction in exacerbations, FEV1% predicted, and a decrease in CS dose. Analysis based on EOS at week 24 (<500 vs. ≥500 cells/μL) demonstrated that the drug's efficacy remained (Figure 1, B). Patients previously treated with Anti IL-5 therapy did not develop more eosinophilia than naive patients. The development of eosinophilia is a common adverse effect in patients with SA treated with Dupilumab; however, therapy response doesn't seem to be related to it.