Researchers from the ALL-MED Medical Research Institute and the Department of Clinical Immunology at Wroclaw Medical University in Poland have validated the use of an allergen exposure chamber (AEC) to assess the safety and effectiveness of house dust mite (HDM) allergen immunotherapy (AIT) in patients with allergic rhinoconjunctivitis.

AECs are used to control allergen challenges for allergic patients by mimicking natural exposure under stable and well-regulated conditions. Fifty HDM-triggered allergic rhinoconjunctivitis patients were included in the study, with HDM allergy being confirmed through skin prick tests, serum-specific IgE, and basophil activation tests. Patients were assessed for exposure to the HDM allergen in the AEC before commencing AIT and after 12 months of treatment.

To assess the effectiveness of AIT, clinical endpoints measured the total nasal symptom score (TNSS), visual analog scale (VAS), and objective parameters such as acoustic rhinometry, peak nasal inspiratory flow (PNIF), and nasal secretion weight. The results demonstrated a statistically significant reduction in TNSS after one year of AIT and a high reduction in nasal symptoms was observed.

"The results indicate that the clinical measurements obtained in the AEC align well with the effectiveness evaluation using the Combined Symptom and Medication Score (CSMS) in real-life conditions,” said Professor Marek Jutel from the Department of clinical immunology at Wroclaw Medical University.

Jutel said the AEC could serve as an alternative to traditional trial designs. and the Total Nasal Symptom Score (TNSS) could act as a reliable primary endpoint in clinical trials. “However, nasal provocation tests (NPT) may not be suitable as a primary endpoint since they do not correlate well with CSMS in real-life conditions and TNSS in the AEC.”