Dupilumab in Type 2-Inflamed COPD Across the Full Spectrum of Airflow Limitation: An Italian Multicentre Retrospective Cohort Study

This multicentre retrospective cohort study describes lung function and patient-reported outcomes in adults with chronic obstructive pulmonary disease (COPD) and type 2 inflammation who received add-on dupilumab in routine clinical care at six Italian centres. During the study period dupilumab was not reimbursed for COPD in Italy and was provided exclusively through the manufacturer's named-patient compassionate-use programme. Access to that programme required a documented blood eosinophil count of at least 300 cells/microliter, at least two moderate or one severe exacerbation in the preceding 12 months, and persistent symptoms despite maximal inhaled therapy, but set no upper or lower limit on the degree of airflow limitation. As a consequence, the cohort includes participants whose airflow limitation falls outside the post-bronchodilator forced expiratory volume in 1 second (FEV1) window of 30 to 70 percent predicted that was required for entry into the BOREAS and NOTUS registration trials. Post-bronchodilator spirometry, COPD Assessment Test (CAT) score, modified Medical Research Council (mMRC) dyspnoea grade and, where locally available, fractional exhaled nitric oxide (FeNO) were recorded at treatment initiation and at approximately 12 weeks. The variable of primary interest is the change from baseline in post-bronchodilator FEV1 at 12 weeks, the timepoint pre-specified for the lung function endpoint of the registration trials. A pre-specified analysis compares the change in FEV1 between participants whose baseline FEV1 falls inside the 30 to 70 percent predicted window and those whose baseline FEV1 falls outside it. The study is observational and non-interventional. Dupilumab was prescribed independently of the study, according to clinical judgement and the rules of the compassionate-use programme, and no study-specific procedure was performed. Data were abstracted from routine clinical records.

Inclusion Criteria: * Age 18 years or older * Physician diagnosis of COPD with post-bronchodilator FEV1/FVC ratio below 0.70 * Documented blood eosinophil count of at least 300 cells/microliter at screening * At least two moderate or one severe COPD exacerbation in the previous 12 months * Persistent symptoms despite maximal inhaled therapy * Started dupilumab 300 mg subcutaneously every two weeks as add-on therapy between October 2024 and April 2026 under the manufacturer's named-patient compassionate-use programme * Post-bronchodilator spirometry available at baseline and at approximately 12 weeks Exclusion Criteria: * Dupilumab started for a primary indication other than COPD * Post-bronchodilator spirometry not available at baseline or at the 12-week assessment * Pre-bronchodilator values only, with no post-bronchodilator measurement recorded