Progress in the development of specific immunotherapies for house dust mite allergies

Abstract

Allergen-specific immunotherapy is used to treat patients exposed and co-sensitized to the two common house dust mites, Dermatophagoides pteronyssinus and Dermatophagoides farinae. Based on seroepidemiological studies and a detailed characterization of mite allergens, an optimal immunotherapeutic product should associate extracts from the two Dermatophagoides species, and include both bodies and fecal particles. Both subcutaneous and sublingual immunotherapies performed with aqueous mite extracts are safe and efficacious in children and adults with mite-induced rhinitis and/or asthma. Double-blind placebo-controlled studies are conducted to further document the efficacy of immunotherapeutic products, with promising results that were obtained already with sublingual tablets. Current developments of second-generation products relying upon recombinant allergens and peptides are reviewed.

Keywords::

• allergen
• Dermatophagoides
• house dust mite
• immunotherapy
• vaccine

Financial & competing interests disclosure

The author is an employee of Stallergenes. The author has no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Products for immunotherapy of house dust mite allergic patients should recapitulate natural exposure and sensitization conditions at a molecular level, that is, they should combine allergen extracts from both Dermatophagoides pteronyssinus and Dermatophagoides farinae, including bodies and feces from the two species.

• The quality and consistency of house dust mite extracts are critical to their safety and efficacy, and thus, only pharmaceutical-grade well-characterized extracts should be used for allergen immunotherapy.

• Patient heterogeneity should be better understood, regarding both type/severity/chronicity of symptoms and immune status.

• Dosing regimens and duration of mite-specific immunotherapy to reach sustained efficacy and a disease-modifying effect should be documented in both challenge chamber studies and long-term field studies.

• Clinical endpoints to measure clinical benefit, and clinical relevance (size of the effect anticipated from allergen immunotherapy) should be defined in collaboration with regulatory authorities.

• Biomarkers associated with clinical efficacy should be identified and developed as companion diagnostics.