PURPOSE: To compare the efficacy of levalbuterol HFA (LEV) 90 μg (2 actuations of 45 μg) with placebo (PBO, 2 actuations) administered via metered dose inhaler (MDI) in the prevention of exercise-induced bronchospasm (EIB) in patients with mild/moderate asthma.
METHODS: Patients ≥18 years participated in a randomized, double-blind, placebo-controlled, 2x2 crossover study. Patients had a ≥6-month history of EIB, ≥70% predicted FEV1 at baseline, and 20-50% decrease in FEV1 following standardized treadmill exercise challenge using single-blind PBO MDI. Eligible patients (n=15) self-administered LEV or PBO 30 minutes prior to exercise challenge. Treatment sequences were separated by a 3-7-day washout. Spirometry was performed predose, 20 minutes postdose/pre-exercise, and at 5, 10, 15, 30, and 60 minutes post-exercise. The primary endpoint was the maximum percent (%) decrease in FEV1 from baseline (postdose/pre-exercise). Area under curve for the % decrease from baseline FEV1 (FEV1 AUC[0-60 min]) and percentage of protected (≤20% decrease in post-exercise FEV1) patients were also assessed.
RESULTS: Compared with the maximum % decrease in FEV1 for PBO (adjusted mean ±SE: 22.5±2.8%), LEV (4.8±2.8%) demonstrated a significantly smaller (p<0.001) decrease in post-exercise FEV1. Significantly superior bronchoprotection was also observed for LEV (adjusted mean ±SE: 148.0±148.5%-min) in comparison with PBO (957.7±148.7%-min; p<0.001) for the % decrease in FEV1 AUC(0-60 min). A significantly higher percentage of LEV-treated patients (93.3%) were protected from EIB than PBO-treated patients (53.3%, p=0.0143). After LEV, 80.0% of patients had a <10% decrease in post-exercise FEV1 compared with 13.3% of patients after PBO. LEV was generally well tolerated.
CONCLUSION: In this trial, LEV HFA MDI 90 μg provided significant protection from EIB.
CLINICAL IMPLICATIONS: Levalbuterol HFA MDI may be beneficial for asthmatic patients with EIB. Support for this study provided by Sepracor Inc.
DISCLOSURE: W. Andrews, Employee Dr. Andrews, and Ms. Huang and Schaefer, are employees of Sepracor Inc.; Consultant fee, speaker bureau, advisory committee, etc. Drs. Pearlman and Rees are investigators for Sepracor Inc.; Other Support for this study provided by Sepracor Inc.