Inhaled Lidocaine for the Treatment of Asthma: Lack of Efficacy in Two Double-Blind, Randomized, Placebo-Controlled Clinical Studies

Abstract

BACKGROUND: Asthma with severe or persistent exacerbations is treated with chronic oral corticosteroids (OCS), such as prednisone. Although efficacious, OCS treatment is often associated with side effects; thus, corticosteroid-sparing treatments are needed. METHODS: We conducted two double-blind, placebo-controlled, clinical studies assessing lidocaine solution for inhalation (LSI; 40 mg twice daily; eFlow(®) nebulizer) to treat asthma. Study 1-Mild/Moderate included 154 patients with mild-moderate asthma [forced expiratory volume in one second (FEV(1)) ≥60% predicted, and ≥12% improvement in FEV(1) (L) after short-acting, inhaled β-agonist; no OCS or inhaled corticosteroids (ICS) in previous month] and evaluated whether FEV(1) improved after 12 weeks of treatment. Study 2-OCS included 114 patients with more severe asthma (FEV(1) 35-85% of predicted values, treatment with OCS for ≥6 months, average daily dose between 5 and 70 mg prednisone or equivalent, stable ≥30 days) and evaluated whether 20 weeks of treatment had a corticosteroid-sparing effect, measured as reduced need for OCS. RESULTS: LSI did not improve pulmonary function in Study 1-Mild/Moderate, and did not have a corticosteroid-sparing effect in Study 2-OCS, when compared with placebo. Thus, the primary efficacy endpoints were not met. Significant improvements were not observed for asthma symptom scores, morning and evening peak expiratory flow values, FEV(1) % predicted, proportion of patients with asthma instability, and asthma quality-of-life scores at week 12 (Study 1-Mild/Moderate) or week 20 (Study 2-OCS). LSI was well tolerated. CONCLUSIONS: These results indicate that lidocaine solution for inhalation is not a useful treatment for asthma; it did not improve pulmonary function and did not have a corticosteroid-sparing effect.