Baseline FeNO Independently Predicts the Dupilumab Response in Patients With Moderate-to-Severe Asthma

Fractional exhaled nitric oxide (FeNO) may have a role both as a prognostic and predictive biomarker, in combination with eosinophils, for assessing responsiveness to some biological therapies.We evaluated the value of baseline FeNO, adjusted for baseline blood eosinophil levels and other clinical characteristics, as an independent predictor of treatment response to dupilumab in patients with uncontrolled, moderate-to-severe asthma.We performed a post-hoc analysis of LIBERTY ASTHMA QUEST (NCT02414854), a phase 3, double-blind study in patients aged ≥ 12 years with uncontrolled moderate-to-severe asthma who received dupilumab 200/300 mg, or placebo every 2 weeks up to 52 weeks. Annualized event rate (AER) of severe exacerbations and least squares mean change from baseline in pre-bronchodilator forced expiratory volume in 1 s (FEVAER increased with increasing baseline FeNO in placebo, and decreased in dupilumab groups. The relative risk of severe exacerbations was 22·7%, 58·3%, and 69·3% lower for dupilumab vs placebo for the FeNO25, 25 to50, and ≥ 50 ppb subgroups. The magnitude of FEVIncreased baseline FeNO was associated with greater clinical effects in dupilumab vs placebo, independent of eosinophil levels and other clinical characteristics.