Optimising treatment for severe asthma.

The treatment landscape in severe asthma is changing rapidly, with multiple new therapies emerging that promise to transform patient outcomes. In a patient who is not responding to conventional therapy with inhaled corticosteroids and long-acting β2-agonists, it is important to first consider if the diagnosis of asthma is correct and, second, to reflect on whether readily modifiable factors are contributing to poor asthma control. In selected patients it may be appropriate to consider a modified n-of-1 trial of add-on therapies such as long-acting anti-muscarinic agents, leukotriene blockers, theophylline or low dose macrolide antibiotics. A number of monoclonal antibodies are now available that target the molecular pathways that contribute to asthma pathogenesis, and more such agents are likely to emerge in the near future. These biologicals can be transformative in selected patients, markedly reducing the frequency of asthma exacerbations, and allowing many patients to reduce or eliminate their use of long term oral corticosteroids. If the promise of personalised treatment is to be fully realised, it is important that better methods are developed to target these new and expensive treatments to patients most likely to respond. The ultimate goal of inducing remission or cure of asthma is still some distance away.