The single mediator approach to asthma therapy: is it so unreasonable?

Asthma involves a complex syndrome of respiratory pathologies that ultimately results in bronchial obstruction and reduced lung ventilatory capacity. Inflammation of the respiratory tract underlies this disease and can be linked to the production and release of multiple mediators of bronchoconstriction and airway wall restructuring and obstruction. Disease triggers vary between patients and include allergens, exercise, inhaled irritants and virus infections. Disease severity can also be highly variable from patient to patient. All of this indicates a heterogeneous disease phenomenon. Bronchodilator drugs that induce rapid symptom relief are just one component of conventional asthma therapy. The use of controller agents, such as anti-inflammatory glucocorticoids, constitutes the other important treatment option. The question is whether a key mediator is released in asthma that can be targeted by either single or multiple therapeutic agents to halt or reverse this complex mix of disease processes.