Characterization of long-acting beta₂-adrenergic agonists utilization in asthma patients

Because of the serious safety risks, Food and Drug Administration (FDA) has recommended that long-acting beta₂-adrenergic agonists (LABAs) be reserved for patients whose asthma cannot be adequately managed with asthma control medication. The objective of the study is to assess prescribing patterns for LABAs prior to the FDA's drug safety communication issued on 2 June 2010.

Data were extracted from IMS Health Plan Claims database for asthma patients who had a new LABA therapy during 2005-2009. The proportion of LABA incident episodes preceded by inhaled corticosteroid (ICS) or leukotriene receptor antagonists (LTRAs) was examined. The medication-concurrent ratio (MCR), defined as the ratio of overlapping therapy days of single-ingredient (SI) LABAs and non-LABA products to the total days of SI LABAs, was calculated. Four criteria were used to estimate poorly controlled asthma prior to LABA initiation.

Of the 228 047 asthma patients, fixed-dose combination (FDC) LABAs were used by the majority of patients (96%). Prior use of ICS or LTRAs was observed in 64% and 31% of SI and FDC LABA incident episodes, respectively. The median MCR for SI LABAs was 62%. Approximately half of the patients met at least one criterion for poorly controlled asthma prior to LABA use.

Substantial proportion of patients was prescribed LABAs without prior use of ICS or LTRAs, or other indicators of poor asthma control. These findings suggest that asthma guidelines were not entirely followed in clinical practice during the study period.