Role of indacaterol in the management of asthma and chronic obstructive pulmonary disease

Indacaterol is the first of a new category of inhaled b2-agonists with a very long duration of action that allows for once-daily administration. The bronchodilation induced by indacaterol is more persistent than that caused by the current long-acting b2-agonists (LABAs; salmeterol and formoterol), and therefore, for this new compound, the word ‘ultra-LABA’ has been created. Indacaterol is an agonist with high intrinsic efficacy and a rapid onset (bronchodilation may reach a maximum after 5–30 min) similar to salbutamol and formoterol, but with a longer duration of action. The long-lasting bronchodilation up to 24 h has been largely demonstrated in several single-dose or short-term treatment studies with different doses of indacaterol. The increase in the forced expiratory volume in 1 s measured 24 h after indacaterol administration may reach up to 300 ml in asthma and 200 ml in chronic obstructive pulmonary disease (COPD). This long-lasting stabilization of the airway caliber may potentially translate into a reduced mechanical stress on the airways, and this might lead to a lower rate of exacerbations and other positive clinical consequences (improvement in exercise capacity and quality of life); these effects have not been confirmed yet with indacaterol. Long-term studies up to 52 weeks in COPD have confirmed these positive effects on patient-related outcomes. The comparison between indacaterol and other long-acting bronchodilators in COPD patients confirms that indacaterol has an efficacy profile similar and often better than that of LABAs or tiotropium. The safety profile is good and no relevant cardiovascular effects have been demonstrated in all clinical studies. Therefore, indacaterol has the characteristics for representing a new important resource for the treatment of COPD.