Efficacy of Dupilumab in Patients with Severe Asthma and Co-existing COPD

<bold>Introduction:</bold> Dupilumab, a monoclonal antibody targeting IL4-Rα, has demonstrated efficacy in reducing exacerbations in both severe asthma (SA) and chronic obstructive pulmonary disease (COPD). SA is often late-onset, and many patients have coexisting COPD. These patients are, however, generally excluded from clinical trials, and hence little is known about their benefit from anti-IL4-Rα therapy. <bold>Aim:</bold> Compare treatment responses to anti-IL4-Rα therapy in patients with combined SA+COPD, versus patients with SA only. <bold>Methods:</bold> The Danish Severe Asthma Register is a complete nationwide prospective cohort of patients with SA receiving biologics. All patients with at least one year of complete follow-up were included, and stratified according to coexisting COPD, defined as forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) < 0.70, a tobacco exposure of at least 10 pack-years and age > 40 yr. <bold>Results:</bold> A total of 161 patients were included, 44% (71 patients) had co-existing COPD. After 12 months of therapy, the mean reduction in exacerbations was comparable among SA+COPD vs SA only patients: 67.0% (SD=40.6) vs 67.5% (50.4), p=0.95. Mean mOCS daily dose was reduced by 3.1mg (3.0) in SA+COPD and 4.7mg (7.1) in SA, p=0.35. Mean ACQ-6 score improved by 1.0 (1.4) in SA+COPD vs. 1.1 (1.2) in SA only, p=0.80. However, the proportion of patients with a complete response (no exacerbations and no mOCS after 12 months) tended to be less among SA+COPD patients (45% versus 61%, p=0.07). <bold>Conclusion:</bold> Comorbid COPD in patients with SA is common and does not reduce the efficacy of dupilumab on exacerbations, mOCS dose or symptom-scores, but may affect the chance of complete response, that is no exacerbations or need for OCS