Comparison of allergenic extracts from different origins: the value of the FDA’s bioequivalent allergy unit (BAU)

ABSTRACT

Introduction: 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.

Areas covered: 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.

KEYWORDS:

• Allergy immunotherapy
• bioequivalent allergy unit
• grass pollen allergy
• index of reactivity
• standardized quality tablet unit

Declaration of interest

G Passalacqua has received speaker’s fees from ALK-Abelló, AstraZeneca, GlaxoSmithKline, Meda, Menarini and Novartis; and has served as a consultant for Lofarma s.p.a. and Stallergenes-Greer. J Sastre has served as a consultant to FAES Farma, Genentech, GlaxoSmithKline, LETI, MSD, Novartis, Roche, Sanofi and Thermo Fisher Scientific; has received lecturing fees from FAES Farma, GlaxoSmithKline, LETI, Novartis and Stallergenes-Greer; and has received grant support for research from ALK-Abelló, GlaxoSmithKline and Thermo Fisher Scientific. O Pfaar has received grants from ALK Abello, Allergopharma, Stallergenes-Greer, HAL Allergy, Allergy Therapeutics/Bencard, Lofarma, Novartis/Leti, Biomay, Nuvo, Circassia, Biotech Tools s.a. for his institution and personal fees from HAL Allergy, Allergy Therapeutics/Bencard, Lofarma, Novartis/Leti, MEDA, ALK Abello, Allergopharma, Anergis, Biotech Tools s.a., Sanofi, Mobile Chamber Experts (a GA²LEN Partner), Pohl-Boskamp, and Stallergenes-Greer for consulting/advisory board services and/or as speaker and/or for (coordinating) investigator services and/or for educational material and non-financial support from HAL Allergy (travel support) for the last three years. O Pfaar is the current chairman of the Immunotherapy Interest Group (IT IG) of the European Academy of Allergy and Clinical Immunology (EAACI) and the secretary of the ENT section of the German Society for Allergology and Clinical Immunology (DGAKI). U Wahn has received consulting fees from Allergopharma, Danone, Hipp, Merck, Novartis and Stallergenes-Greer; honoraria for lectures from ALK-Abelló, Allergopharma, Allergy Therapeutics, LETI, MSD, Nestlé, Novartis, Nutricia and Stallergenes-Greer; and research funding from Stallergenes-Greer. P Demoly has served as a consultant and speaker for ALK-Abelló, AstraZeneca, Chiesi, Stallergenes-Greer and Thermo Fisher Scientific; and was a speaker for Allergopharma, AllergyTherapeutics, GlaxoSmithKline, Menarini and Merck in 2010–16. Medical writing assistance in the preparation of this manuscript was provided by James Reed of Newmed Publishing Services, and funded by Stallergenes-Greer. The authors have 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.