Abstract RATIONALE: Albuterol-budesonide 180/160 µg is indicated in the US for as-needed treatment or prevention of bronchoconstriction and to reduce risk of exacerbations in patients ≥18 years old with asthma. The objective of the ALbuterol-budesonide Treatment in Acute airway obstruction (ALTA) study (NCT05555290) is to assess comparative efficacy, safety, and mechanisms of action of albuterol-budesonide 180/160 µg versus albuterol 180 µg in treating and preventing bronchoconstriction. This report describes the clinical profiles of patients meeting criteria for randomization into the trial. METHODS: ALTA is a phase 3b, multicenter, randomized, double-blind, 2-period, cross-over study evaluating the effects of repetitive dosing of albuterol-budesonide 180/160 µg versus albuterol 180 µg for treating adults treated as intermittent asthma and experiencing acute airway obstruction induced by repeated mannitol challenges. Inclusion criteria evaluated during screening include asthma diagnosis ≥6 months, prescribed and utilizing albuterol as the only asthma treatment for ≥4 weeks, pre-bronchodilator FEV1 ≥1.50 L and FEV1 ≥60% to <90% predicted, and positive response to a mannitol challenge (decrease in FEV1≥15% at ≤635 mg cumulative mannitol dose). Exclusion criteria include clinically significant lung disease other than asthma; any smoking in the prior 6 months or ≥10 pack-year smoking history; or a clinical encounter for asthma worsening within the past 4 weeks. RESULTS: Thus far, 84 patients have met the criteria for randomization into ALTA. Mean(SD) age=44.9(13.7) years, 56.0% female, 40.5% African American, 9.5% Hispanic/Latino. Clinical characteristics include 10.7% with 1 prior-year severe exacerbation; mean(SD) fractional exhaled nitric oxide=37.0(37.4) ppb; mean(SD) baseline pre-bronchodilator FEV1=2.464(0.538) L; mean(SD) baseline percent predicted FEV1=76.7(7.9)%; mean(SD) % fall in FEV1 with mannitol challenge=22.1(7.3)% at a mean(SD) cumulative mannitol dose of 146.4(176.3) mg. Despite being treated for intermittent asthma, based upon symptoms, lung function, and exacerbation history, no patients met NAEPP 2007 criteria for intermittent disease, and 13.1% fell into the mild, 78.6% moderate, and 8.3% severe persistent asthma categories (Figure). With respect to asthma control, as measured by Asthma Impairment and Risk Questionnaire scores, 60.7% had well-controlled, 20.2% not well-controlled, and 19.1% very poorly controlled disease. CONCLUSION: The baseline characteristics of patients in the ALTA study reveal that patients treated as intermittent asthma exhibit heterogeneity in clinical characteristics, airway hyper-reactivity, T2 inflammation, and disease severity and control. Additional genomic and biomarker data are forthcoming and altogether will provide an opportunity to address the mechanism of albuterol and budesonide interactions in a broad spectrum of asthma phenotypes.
ALbuterol-budesonide Treatment in Acute Airway Obstruction: Design of the ALTA Study