A high-dose, depigmented polymerized birch pollen extract for subcutaneous allergen immunotherapy has a favourable efficacy/safety ratio.

"CONFLICT OF INTEREST STATEMENT Oliver Pfaar reports grants and/or personal fees from ALK‐Abelló, Allergopharma, Stallergenes Greer, HAL Allergy Holding B.V./HAL Allergie GmbH, Bencard Allergie GmbH/Allergy Therapeutics, Lofarma, ASIT Biotech Tools S.A., Laboratorios LETI/LETI Pharma, GlaxoSmithKline, ROXALL Medizin, Novartis, Sanofi‐Aventis and Sanofi‐Genzyme, Med Update Europe GmbH, streamedup! GmbH, Pohl‐Boskamp, Inmunotek S.L., John Wiley and Sons, AS, Paul‐Martini‐Stiftung (PMS), Regeneron Pharmaceuticals Inc., RG Aerztefortbildung, Institut für Disease Management, Springer GmbH, AstraZeneca, IQVIA Commercial, Ingress Health, Wort&Bild Verlag, Verlag ME, Altamira Medica AG, Meinhardt Congress GmbH, Deutsche Forschungsgemeinschaft, Thieme, Deutsche AllergieLiga e.V., AeDA, Procter and Gamble, Alfried‐Krupp Krankenhaus, Red Maple Trials Inc., Technical University Dresden, ECM Expo& Conference Management, all outside the submitted work; and he is member of EAACI Excom, member of ext. board of directors DGAKI; coordinator, main‐ or co‐author of different position papers and guidelines in rhinology, allergology and allergen‐immunotherapy. Angelika Sager is an employee of LETI Pharma GmbH. Ralph Mösges reports grants and personal fees from LETI Pharma within the scope of the present work. He also reports recent grants, personal fees, and non‐financial support (all outside the scope of the present work) from ALK, Allergopharma, Allergy Therapeutics, Angelini Pharma, ASIT biotech, Atmos, Bayer, Bencard, Bionorica, bitop, Cassella‐med GmbH and Co. KG, FAES, Ferrero, Friulchem, GSK, HAL BV, Hexal, Hulka, Inmunotek, JGL, Johnson&Johnson, Klosterfrau, Laboratoire de la Mer, Lek, Lofarma, Meda, Menarini, Menarini, Merck Sharp and Dohme, Mundipharma, Novartis, Nuvo, Optima, Otonomy, Pohl‐Boskamp, PRO‐AdWise, Roxall, Sanofi, Servier, Sidroga, Stada, Stallergenes, UCB, and Ursapharm. Margitta Worm declares the receipt of honoraria and/or consultation fees by the following companies: Novartis Pharma GmbH, Sanofi‐Aventis Deutschland GmbH, DBV Technologies S.A, Aimmune Therapeutics UK Limited, Regeneron Pharmaceuticals, Inc, Leo Pharma GmbH, Boehringer Ingelheim Pharma GmbH &Co.KG, ALK‐Abelló Arzneimittel GmbH, Lilly Deutschland GmbH, Kymab Limited, Amgen GmbH, Abbvie Deutschland GmbH and Co. KG, Pfizer Pharma GmbH, Mylan Germany GmbH (A Viatris Company), AstraZeneca GmbH, Lilly Deutschland GmbH, and GlaxoSmithKline GmbH and Co. KG."

"The study was funded by LETI Pharma GmbH (Witten, Germany). Editorial assistance was provided by David Fraser (Biotech Communication SARL, Ploudalmézeau, France) and funded by LETI Pharma GmbH."

"All participants gave their written consent for participation after being informed of the study objectives and procedures. The study was approved by the appropriate independent ethics committees in each country and registered in the European Clinical Trials Database (reference: EudraCT 2008‐008448‐26). The study was carried out in accordance with the Declaration of Helsinki and the International Conference on Harmonisation E6 guideline on good clinical practice (CPMP/ICH135/95) and the appropriate local regulations and legislation."