title: Comparison of allergenic extracts from different origins: the value of the FDA's bioequivalent allergy unit (BAU).
abstract: BACKGROUND
  Allergy immunotherapy (AIT) is the only disease-modifying intervention for the treatment of allergic diseases. The clinical effectiveness of AIT is clearly dose-dependent, so it is important that clinicians can assess and compare the potency of the various products available. However, this is not possible in practice, because manufacturers use different methods to determine potency. Therefore, a clear need exists for adoption of a 'gold-standard' measure of allergenicity. The bioequivalent allergy unit (BAU) is thus far the only allergen unit approved by a regulatory agency (the US Food and Drug Administration), with European regulatory authorities yet to adopt a common unit.
  
  
  METHODS
  Using PubMed, we performed a review of the literature on measures of allergen extract potency, use of the BAU, and BAU assessment for grass pollen tablets. Expert commentary: There is an obvious benefit to allergists and patients for having a single, comparable unit across products, and we strongly support the adoption of a single, 'gold-standard' unit of measurement for all products. Use of the BAU allows a clear comparison of the potency of allergen products from different manufacturers, and enables better understanding of the potential reasons for any differences in administration and dosing protocols between these products.
authors.affiliation: a Allergy and Respiratory Diseases, IRCCS San Martino-IST , University of Genoa , Genoa , Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Passalacqua
authors.affiliation: b Allergy Division, Fundación Jimenez Díaz, CIBER of Respiratory Diseases, Institute Carlos III , Universidad Autónoma de Madrid , Madrid , Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Sastre
authors.affiliation: c Center for Rhinology and Allergology , Wiesbaden , Germany.|d Department of Otorhinolaryngology, Head and Neck Surgery, Medical Faculty Mannheim , Universitätsmedizin Mannheim, Heidelberg University , Mannheim , Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Pfaar
authors.affiliation: e Department of Paediatric Pulmonology and Immunology, Charité Virchow-Klinikum , Humboldt University , Berlin , Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wahn
authors.affiliation: f Department of Pulmonology, Division of Allergy , Hôpital Arnaud de Villeneuve, University Hospital of Montpellier, Montpellier and Sorbonne Universities , UPMC Paris 06, UMR-S 1136, IPLESP, Equipe EPAR, Paris , France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Demoly
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D003888:Desensitization, Immunologic / Q000379:methods*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000628:therapy*; D010936:Plant Extracts / Q000276:immunology*; D011058:Pollen / Q000276:immunology*; D012015:Reference Standards; D012016:Reference Values; D014481:United States; D014486:United States Food and Drug Administration
chemical_list: D000485:Allergens; D010936:Plant Extracts
keywords: Allergy immunotherapy; bioequivalent allergy unit; grass pollen allergy; index of reactivity; standardized quality tablet unit