The journal of allergy and clinical immunology. In practice 2025 Feb 14
Profiling Blood Hypereosinophilia in Patients on Dupilumab Treatment for Respiratory Conditions: A Real-Life Snapshot.
Abstract
Background
A transient and usually asymptomatic increase in blood eosinophil count (BEC) associated with dupilumab treatment has been described. Predicting factors related to the increase in BEC and the occurrence of symptoms are still poorly investigated.
Objective
To investigate frequency, timing, duration, clinical relevance, and potential predictors of the increase in BEC in a real-life multicenter cohort of patients affected by asthma and/or chronic rhinosinusitis with nasal polyps (CRSwNP) treated with dupilumab.
Methods
BEC and clinical conditions at baseline and every 3 months after the start of dupilumab treatment were assessed. Any adverse drug reaction was also recorded. Remission of dupilumab-associated eosinophilia was defined by follow-up BEC values <0.5 × 109 cells/L.
Results
Overall, 108 of 195 (55%) patients experienced an increased BEC after dupilumab initiation, but only 29 of 195 (14.9%) showed hypereosinophilia. BEC peak occurred 6 months after the start of treatment and resolved after 9 months (median time). The probability of developing hypereosinophilia was 3.3 times higher in patients with the baseline BEC between 0.5 × 109 and 1.5 × 109 cells/L. The occurrence of symptoms during BEC peak was higher in patients with comorbidities and in patients showing any increase in BEC.
Conclusions
In a real-life setting, dupilumab treatment in patients with asthma and/or CRSwNP was often associated with a transient increase in BEC, but hypereosinophilia rarely occurred. Onset of symptoms co-occurring with BEC peak was observed in a minority of subjects. BEC should not preclude dupilumab initiation or continuation but should be monitored for at least 8 months after treatment begins, particularly in the case of baseline eosinophilia/hypereosinophilia and/or comorbidities.
Related Questions
How often, if at all, do you monitor a CBC with differential to assess peripheral eosinophilia in patients with type 2 inflammatory asthma who have been started on dupilumab?
For most patients, a baseline CBC with differential followed by a recheck at approximately 3 months aligns with the observed pharmacokinetics of eosinophil rebound. GINA 2026 notes transient blood eosinophilia occurs in 4–13% of patients, with rare EGPA cases potentially unmasked following OCS reduc...
Would you stop Dupixent in an asthma patient who has good asthma control and notes improvement in loss of smell, but shows notable eosinophil elevation after 4-5 doses of the medication?
Transient eosinophilia has been reported in patients treated with Dupixent, likely related to downregulation of eotaxin and adhesion molecules resulting in impaired eosinophil migration into the tissues (Castro et al., PMID 29782217, Olaguibel et al., PMID 35522053). This phenomenon is typically see...