Prevalence and impact of hypereosinophilia in severe asthma treated by dupilumab: an observational analysis

Dupilumab blocks IL4 and IL13 signaling. Despite its efficiency in severe eosinophilic asthma, the potential of inducing hypereosinophilia (HE) is a concern. We aimed to investigate the prevalence and consequences of HE due to dupilumab in a real-world setting. Data of asthma patients receiving dupilumab in UMC Amsterdam were analyzed. They were evaluated every 2 weeks during the first 4 months. If available, eosinophil measurements thereafter were also considered. Out of 50 patients, 29 signed consent for Rapsodi registry ánd had longitudinal eosinophil measurement available. Median age was 55 years, FEV1 88.5%, 44,8% were male, 69% had nasal polyps, 48% were on oral corticosteroids (OCS) and 72% had previous anti-IL5 treatment. In 10 patients (34%), eosinophils >1500/mL were measured during follow up. The timing of HE was variable (figure). The number of months treated with anti-IL5 before was the only difference between patients with and without HE (22 vs 10 months, p=0.03). Of these 10 HE patients, 8 received additional OCS (80% vs 16% in non-HE, p=0.001), 1 had an HE-related severe adverse event and 4 had worse asthma control. 50% discontinued treatment vs 26% in non-HE (p=0.24). In a real-world setting of severe asthma patients, dupilumab induces HE in 34%, which led to more OCS use in comparison with non-HE patients. Previous anti-IL5 treatment seems a risk factor for HE under dupilumab.