RT Journal Article SR Electronic T1 Drug therapies in severe asthma – the era of stratified medicine JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP 452 OP 456 DO 10.7861/clinmedicine.15-5-452 VO 15 IS 5 A1 Kathy J Hetherington A1 Liam G Heaney YR 2015 UL http://www.rcpjournals.org/content/15/5/452.abstract AB Difficult-to-treat asthma affects up to 20% of patients with asthma and is associated with significant healthcare cost. It is an umbrella term that defines a heterogeneous clinical problem including incorrect diagnosis, comorbid conditions and treatment non-adherence; when these are effectively addressed, good symptom control is frequently achieved. However, in 3–5% of adults with difficult-to-treat asthma, the problem is severe disease that is unresponsive to currently available treatments. Current treatment guidelines advise the ‘stepwise’ increase of corticosteroids, but it is now recognised that many aspects of asthma are not corticosteroid responsive, and that this ‘one size fits all’ approach does not deliver clinical benefit in many patients and can also lead to side effects. The future of management of severe asthma will involve optimisation with currently available treatments, particularly corticosteroids, including addressing non-adherence and defining an ‘optimised’ corticosteroid dose, allied with the use of ‘add-on’ target-specific novel treatments. This review examines the current status of novel treatments and research efforts to identify novel targets in the era of stratified medicines in severe asthma.