Emerging therapeutic options for asthma.

Asthma is characterized by eosinophilic airway inflammation and elevated serum immunoglobulin E (IgE) levels. Due to these pathologic features, the foundation of asthma treatment has historically been anti-inflammatory therapy with inhaled corticosteroids (ICSs). Numerous factors in addition to IgE and eosinophils, however, likely play important roles in mediating the airway inflammatory response characteristic of asthma. ICSs are effective therapy for some patients with persistent asthma, but clinical trials have shown that even increasing doses of ICSs under carefully controlled situations does not always result in acceptable asthma control. Consequently, other classes of medications, in addition to ICSs, are recommended in those patients with more severe asthma. The class of medication most commonly used in more severe asthma, along with ICSs, is long-acting inhaled beta2-agonists, but leukotriene modifying agents and anti-IgE monoclonal antibodies may also be used. Agents such as tiotropium, a long-acting inhaled anti-muscarinic agent, and those aimed at inhibiting cytokines, such as mepoluzimab, daclizumab, and etanercept, hold promise in the treatment of asthma. Other agents under investigation include phosphodiesterase type 4 inhibitors and oligonucleotides. Bronchial thermoplasty, a nonpharmacologic option, may also be beneficial in patients with poorly controlled asthma. As our understanding of the complex pathophysiology of asthma increases, it will enable the development of novel therapeutic approaches for patients who are not responding well to traditional treatments. Although more studies are necessary to ensure the efficacy and safety of both pharmacologic and nonpharmacologic approaches, there is future promise for therapeutic advances in severe, persistent asthma.