BACKGROUND: There is an increasing need for allergen inhalation systems to perform basic clinical research and test anti- @entity56 drugs under well-controlled conditions. This requires stability of environmental conditions like temperature and humidity, as well as allergen concentration and reproducible induction of @entity56 . OBJECTIVE: The aim of this study was to validate an environmental exposure unit for controlled @entity1 pollen inhalation studies in @entity1 with @entity2023 . METHODS: Temperature, relative humidity, and air flow rate were kept constant with an air conditioning system. Pollen atmosphere was generated using a specially designed feeding system and monitored online by laser counter and offline using rotating rod samplers. Efficacy (total nasal symptom score, nasal air flow rate, nasal secretion) and safety (lung function) parameters were evaluated at different pollen concentrations and repeated allergen challenges. RESULTS: Temperature, humidity, and air flow rate in the environmental exposure unit remained constant within a range of <2%. The spatial distribution and the temporal stability of the pollen concentration varied only slightly over 4 h (+/-10% and <4%, respectively). Dose-dependent induction of @entity2023 symptoms, reduction in nasal air flow rate, and increase in nasal secretion were observed over time. These effects were reproducible from day to day. Lung function remained clinically normal at all concentrations and from day to day. CONCLUSIONS: Thus, pollen exposure in the environmental exposure unit is an effective, reproducible, safe, and suitable method for single-centre clinical studies on the efficacy of anti- @entity56 treatment or basic clinical research.

Validation of an environmental exposure unit for controlled @entity1 inhalation studies with grass pollen in XXXX with @entity2023 .

@entity1 :: ('9606', 'Species') :: ['participants', 'human'] @entity56 :: ('MESH:D004342', 'Disease') :: ['allergic symptoms', 'allergic'] @entity2023 :: ('MESH:D006255', 'Disease') :: ['seasonal allergic rhinitis', 'allergic rhinitis']
@entity1 :: (9606,Species) :: ['patients']
