Prospects for improved therapy in chronic obstructive pulmonary disease bythe use of levalbuterol

Like asthma, chronic obstructive pulmonary disease (COPD) is a chronic dise ase, the most prominent symptom of which is airway obstruction. Airway infl ammation may be pathogenomic in both diseases, but only in COPD does inflam mation predominate as a determinant of symptoms to make obstruction largely refractory to treatment. Despite a more limited degree of reversibility th an in asthma, beta(2)-agonists are used extensively to reduce airway obstru ction and to achieve symptomatic improvement, with racemic albuterol being widely favored. In asthma, bronchodilation and bronchoprotection largely ac count for symptomatic benefit. In COPD, the capacity of racemic albuterol t o ameliorate these symptoms is more limited and suppression of edema and of infiltration and activation of leukocytes acquire greater significance, Du ring regular use of racemic albuterol in asthma, bronchoprotection diminish es progressively as hyperresponsiveness becomes increasingly pronounced, a process that is associated with an infiltration and activation of eosinophi ls. These paradoxic effects of racemic albuterol may be attributed to pharm acologic actions of the distomer, (S)-albuterol, As would be expected, homo chiral (R)-albuterol (levalbuterol) is more potent and effective in asthma and may have significant advantages if used in COPD, A substantial (4-8-fol d) reduction in the dose of levalbuterol anticipates lesser side effects an d diminished risk in patients with cardiovascular disease, Additionally, th e increased potency and duration of bronchodilation observed in asthma may extend to COPD, Finally, removal of the proinflammatory actions of (S)-albu terol may eliminate the persisting obstruction and decrease elastance that are associated with enhanced inflammation and may allow levalbuterol to sup press edema and diminish leukocyte activation more effectively.