Validation of Strasbourg environmental exposure chamber (EEC) ALYATEC^® in mite allergic subjects with asthma

Abstract

Objective: Environmental Exposure Chamber (EEC) should have standardized and controlled allergenic and non-allergenic exposures to perform reproducible clinical studies. The aim was to demonstrate that mite exposure in the Alyatec^® EEC could induce early (EAR) and/or late asthmatic reactions (LAR) in at least 60% of subjects allergic to mite.

Methods: The EEC has a volume of 147-m³ with 20 seats. The nebulized particle number, airborne Der p1, endotoxins, and volatile organic compound (VOC) concentrations were measured. Twenty-four asthmatics allergic to mite were randomly exposed to 15, 25, and 46 ng/m³ Der p1. Specificity was assessed in not mite-sensitized asthmatics.

Results: No significant endotoxin or VOC contamination was measured. The mean inter-assay CVs were 12.5% for the airborne particle number and 28.7% for airborne Der p1 concentrations. For the three Der p1 concentrations, at least 88% of the subjects developed EAR and/or LAR, and at least 46% developed a dual response. No reaction occurred with placebo or in the control group. No severe bronchial reaction occurred.

Conclusions: The Alyatec^® EEC demonstrated a tight control of allergenic and non-allergenic exposures. The EEC was clinically validated, with airborne Der p1 levels close to levels found in natural settings.

Keywords:

• Mite
• asthma
• environmental experimental chamber
• early asthmatic response
• late asthmatic response

Declarations of interest

FdB has financial interest. AG, IC, NB, AJ, FS, and ND are ALYATEC employees. NK, VD, CR, and LV have no financial interest.

Notes on contributors

FDB, NK, ND, CR, AG, IC, and LV are substantial contributions to conception and design. FDB, NK, and VD are contributing to analysis and interpretation of data and drafting. NB, FS, ND, AJ are contributing to acquisition of data. FDB, AG, IC, NB, AJ, FS, ND, NK, VD, CR, and LV are contributing to revising. FDB, AG, IC, NB, AJ, FS, ND, NK, VD, CR, and LV are contributing to final approval.

Additional information

Funding

This study was sponsored by ALYATEC^®.