Background: Inhaled corticosteroids are the cornerstone of asthma treatment worldwide. In an effort to improve the lung bioavailability of budesonide, a solution of budesonide has been developed by using the cyclodextrin HP-Betadex as an excipient. The solution is suitable for the use with a jet nebulizer or a soft mist inhaler.
 
Aims and objectives: After assessing the absence of toxicity in nonclinical rodent and nonrodent studies, the aim of the first clinical study on the budesonide-HP-Betadex complex (AQ1001S) was to compare its efficacy following a 4 week- inhalation administration (once daily) via a jet nebulizer to a commercially available suspension of budesonide (budesonide dose in each treatment arm: 0.125 mg).
 
Methods: Twenty-three mild and steroid naïve asthmatics were randomized in an active-controlled, multiple dose, two-period crossover study (NCT04933383). The main efficacy parameter was the measurement of bronchial responsiveness measured by a methacholine challenge (PC20M). Safety was evaluated by recording (serious) adverse events.
 
Results: No significant adverse events were observed during the study. PC20M was significantly increased compared to baseline when patients were treated by AQ1001S (p=0.006) but was not significantly modified when patients were treated with commercial budesonide suspension (p=0.633).
 
Conclusion: Budesonide solution (AQ1001S) is more effective at reducing airway responsiveness than budesonide suspension in patients with mild asthma.