Recent advances in chronotherapy for the management of asthma

Asthma is a common inflammatory disease of the airways, with a pronounced circadian variation in symptoms. A number of existing asthma treatments are "chronotherapies" designed to be delivered to coincide with the "morning dip" in lung function and correspond- ing worsening of symptoms. In the past decade, our knowledge of how circadian rhythms are regulated has increased immensely, and increasing evidence that the molecular clock plays a significant role in the immune system makes asthma an intriguing disease to study. The current trend toward once-daily dosing of asthma therapies reduces the need for careful timing of doses; however, patients are exposed to therapeutic levels of the drug and potential side effects for the entire day. Consequently, improved therapeutic benefit in asthma may be gained by under - standing the molecular pathways that drive the predictable, diurnal worsening of symptoms. Furthermore, timing the delivery of therapy to coincide with pathway sensitivity may deliver maximum benefit. Defining the role of the molecular clock in these pathways could therefore lead to novel therapies and improved asthma control.