D3.146 - Impact of Switching from Omalizumab to Dupilumab in Severe Asthma Patients: A Retrospective Evaluation of Efficacy and Inflammatory Biomarkers

Biologics have revolutionized the treatment of severe asthma. Nonetheless, some patients may not respond adequately to the initial treatment requiring a switch to another one. This study assessed the impact of switching omalizumab (OMA) to dupilumab (DUPI) treatment in these patients.

This retrospective analysis included severe asthma patients, treated at a specialized outpatient clinic, who transitioned to DUPI after a period on OMA. Clinical data were collected regarding exacerbations (EXC) and courses of systemic corticosteroids (OCS) per year as well as type 2 inflammation biomarkers (total IgE, blood eosinophils, FeNO) and lung function indicators (pre-bronchodilator (BD) FEV1 and FVC, FEV1/FVC ratio). A paired analysis at T1 (referring to the last year on OMA) and T2 (4–12 months after switching to DUPI) was performed using SPSS v26, with statistical significance defined as p-value < 0.05.

13 patients were included: 46% male, median age 64 years (32–83 years), 69% also had chronic rhinosinusitis with nasal polyposis. The median treatment duration was 6 years for OMA and 10 months for DUPI. After switching to DUPI, there was a significant reduction in the number of EXC/year (p=0.002), with 54% of patients experiencing at least one EXC/year on DUPI compared to 92% on OMA. A reduction in the number of OCS courses/year (p=0.017) and in OCS-dependent patients was also noted: 3 on OMA versus 2 on DUPI, noting that these maintained daily OCS due to other comorbidities but managed to reduce the daily dose. Regarding inflammatory biomarkers, there was a significant decrease in total IgE (p=0.007), with median values of 633kU/L on OMA versus 96kU/L on DUPI, and FeNO (p=0.009), with median values of 28ppb on OMA and 13ppb on DUPI. No significant difference was observed in blood eosinophils (p=0.556). Lung function evaluation revealed a significant increase in pre-BD FEV1 (% of predicted) on DUPI (p=0.028), with a rise of more than 100 mL in 62% of patients following the therapy switch.

Switching to DUPI in non-responders to OMA demonstrated huge clinical benefits, including a reduction in EXC and OCS courses/year, as well as a decrease in type 2 inflammation (reduced FeNO and total IgE). Additionally, a significant improvement in respiratory function was observed, with a notable increase in pre-BD FEV1.