Allergen immunotherapy in asthma; what is new?

Abstract

The use and role of allergen immunotherapy (AIT) in asthma is still a matter of debate, and no definite recommendation about this is made in guidelines, both for the subcutaneous and sublingual routes. This is essentially due to the fact that most controlled randomised trials were not specifically designed for asthma, and that objective measures of pulmonary function were only occasionally considered. Nonetheless, in many trials, favourable results in asthma (symptoms, medication usage, bronchial reactivity) were consistently reported. There are also several meta analyses in favour of AIT, although their validity is limited by a relevant methodological heterogeneity. In addition to the crude clinical effect, a disease modifying action of AIT (prevention of asthma onset and long-lasting effects) have been reported. The safety is an important aspect to consider in asthma. Fatalities were rare: in Europe no fatality was reported in the last three decades, as in the United States in the last 4 years. Based on previous surveys, and common sense, uncontrolled asthma is still recognized as the most important risk factor for severe adverse events. On the contrary, there is no evidence that AIT can worsen or induce asthma. According to the available evidence, AIT can be safely used as add-on treatment when asthma is associated with rhinitis (a frequent condition), provided that asthma is adequately controlled by pharmacotherapy. AIT cannot be recommended or suggested as single therapy. When asthma is the unique manifestation of respiratory allergy, its use should be evaluated case by case.

30 years of sublingual immunotherapy

“…; (b) does AIT elicit or worsen asthma? . The most important meta‐analyses (with their intrinsic limitations) suggested that AIT, and SLIT, are clinically effective in reducing asthma symptoms and medication score, without an increase in adverse events.…”

Impact of Allergen Immunotherapy in Allergic Asthma

“…Both genetic predisposition and environmental exposures are known to be risk factors for asthma. AIT is known to be effective in reducing the risk of asthma onset, and has been progressively applied for the treatment to allergic asthma [33] in combination with pharmacological treatment [34,35]. AIT has been reported to exert a beneficial effect when allergic asthma and rhinitis are concurrent; of note, a substantial share of the current data regarding AIT in asthma was presented in clinical trials designed to target patients with allergic rhinitis whose asthma was a comorbidity [36].…”

“…AIT has been reported to exert a beneficial effect when allergic asthma and rhinitis are concurrent; of note, a substantial share of the current data regarding AIT in asthma was presented in clinical trials designed to target patients with allergic rhinitis whose asthma was a comorbidity [36]. Therefore, measurements of asthma-related outcomes were oftentimes sought out secondarily [34].…”

“…As the only treatment known to alter the natural course of allergic diseases, AIT has been shown to aid in the prevention of asthma onset and allergic rhinitis progression [34]. Back in 1992, the well-known preventive allergy treatment study was initiated to determine whether SCIT is effective in preventing asthma.…”

Allergen-specific immunotherapy in pediatric allergic asthma

“…Severe/uncontrolled asthma remains the main risk factor for side effects due to AIT. Currently, asthma is not an absolute contraindication to AIT, if the patient is well controlled with pharmacotherapy [ 52 53 ].…”