Variation in allergen content in sublingual allergen immunotherapy with house dust mites

Abstract

BackgroundAllergen immunotherapy is a treatment modality which can be applied using different vaccines. The aim of this study was to quantify and compare the allergen content of different house dust mites (HDM)’ sublingual treatments and to review the evidence on their efficacy.MethodsFive sublingual allergen immunotherapy (SLIT) products were ordered and purchased at an ordinary pharmacy and masked for blinding before the study was started. Detection of Dermatophagoides pteronyssinus and Dermatophagoides farinae allergens Der p 1, Der f 1, Der p 2 and Der f 2 was carried out by immunoblotting and fluorescent multiplex. A literature search for meta‐analyses and systematic reviews that included SLIT‐HDM products was performed.ResultsDer p 1 concentrations ranged from 0.6 to 14.5 μg/ml; similar figures were found for Der f 1 that ranged from 0.2 to 12.4 μg/ml. Der p 2+ Der f 2 ranged from 0.2 to 1.5 μg/ml. Data on efficacy are scarce for most of the five products.ConclusionsSubstantial variations regarding allergen content were found among these five SLIT‐HDM products. Therefore, it can be necessary to guarantee the quality of the SLIT‐HDM products and to demonstrate their effectiveness before they are marketed. It seems necessary, for the moment, to take into account these characteristics of the products before prescribing.

Dietary shifts have consequences for the repertoire of allergens produced by the European house dust mite

“…Culture systems and manufacturing methods for each mite species are not harmonized within the industry. This scenario, coupled with the inherent variability associated with biological materials, explains the heterogeneity of products available on the market, which can differ greatly in terms of allergen composition and allergenicity (Brunetto et al ., ; Casset et al ., ; Moreno Benítez et al ., ). Standardization is a main concern for regulatory agencies, as exemplified by the new monographs of the European Pharmacopoeia (01/2017:1063 and 01/2017:2625).…”

Similar biological activity in skin prick test for Oralair® (8200 BAU) and Grazax® (6200 BAU) reinforces effective SLIT dosing level

“…Different investigators have consistently found major differences in the in vitro potency of liquid sublingual allergen immunotherapy (SL‐AIT) extracts available on the European market: manufacturer A dosing between 12 and 45 times was more diluted than manufacturer B over the whole range of allergens tested . To overcome the variability of SL‐AIT liquid dosing and to avoid the need for refrigeration, SLIT tablets were developed: the fast‐dissolving timothy grass pollen (TIM) tablet, Grazax/Grastek ® , and the 5‐grass pollen tablet, Oralair ® .…”

Quality control of house dust mite extracts by broad-spectrum profiling of allergen-related enzymatic activities

“…Our method proved to be compatible with glycerol and phenol, the most common excipients in the formulation of skin prick test and sublingual immunotherapy (SLIT) products . In addition, the sensitivity of our method allows the analysis of highly diluted extracts (0.75 μg Der p 1/ml and 0.63 μg Der p 2/ml), equivalent to the lowest concentrated products cited in the literature . Further investigation is needed to confirm compatibility with other AIT products (e.g.…”