Sublingual allergen immunotherapy (SLIT) tablets — which expose patients to allergens to desensitise them — have been explored in patients with allergic disease and house dust mite (HDM) sensitisation, but they have not yet been shown to affect asthma control.
Researchers conducted a randomised trial in which they assigned 834 adults with poorly controlled allergy-related asthma to either one of two doses of SLIT or placebo, both combined with inhaled corticosteroid (ICS) and salbutamol treatment. They assessed efficacy over six months during which ICS dosage was gradually reduced.
Both doses of SLIT significantly reduced the risk of moderate or severe asthma exacerbation by around 30% compared with placebo. However, there was no significant difference in asthma control or asthma-related quality of life according to questionnaires.
Reporting in JAMA (online, 26 April 2016)
, the researchers say that further studies are needed to assess long-term efficacy.
 Virchow JC, Backer V, Kuna P et al. Efficacy of a house dust mite sublingual allergen immunotherapy tablet in adults with allergic asthma: a randomised clinical trial. JAMA 2016;315:1715–1725. doi: 10.1001/jama.2016.3964