A multicenter double-blind randomized trial to evaluate Levalbuterol (LEV) vs Racemic Albuterol (RAC) in acute severe asthma.
Among 627 adult patients in this trial, 315 received LEV 1.25 mg and 312 received RAC 2.5 mg. Drug was nebulized every 20 min for 3 doses, then every 40 min for doses 4 to 6. All patients received systemic steroids at the initiation of treatment. FEV1 and clinical improvement were evaluated before each dose until discharge or hospital admission.
Asthma severity was similar in both LEV and RAC patients, based on presenting FEV1, prior reported rescue medication and corticosteroid use. FEV1 improvement was significantly greater in the LEV-treated patients after the first dose (LEV 0.50 L vs. RAC 0.43 L; difference (D)= 0.07L 95% CI 0.01-0.14L). Treatment differences of similar magnitude persisted after the last dose. Differences were greatest in patients without prior steroid therapy (LEV 0.58 L vs. RAC 0.45L; D= 0.13L, 95% CI 0.04-0.22L), and among the 379 patients who improved sufficiently to be discharged after < 3 doses (LEV 0.68L vs. RAC 0.55L: D= 0.12L, 95% CI 0.04 - 0.21L). In patients with plasma (S)-albuterol levels measured at presentation (n=160), these levels (reflecting prior recent RAC use) were associated with hospital admission (p<0.01) and inversely associated with FEV1 improvement, results most pronounced in RAC-treated patients.
In this study, LEV resulted in faster and greater FEV1 improvement than RAC. Plasma (S)-albuterol levels positively correlated with admission and inversely correlated with FEV1 improvement.
This study suggests that LEV may be a more effective bronchodilator than RAC in acute severe asthma.
N. Hanania, Clinical Investigator for Sepracor Inc.