Nasal allergen challenge: standardisation as a surrogate for hay fever
Research type
Research Study
Full title
Nasal Allergen Challenge: standardisation as a surrogate for hay fever
IRAS ID
266165
Contact name
Stephen R Durham
Contact email
Sponsor organisation
Imperial College London
Duration of Study in the UK
0 years, 2 months, 28 days
Research summary
Hay fever affects 1 in 4 in the UK and has significant effects on the quality of life of sufferers. It is also associated with the development of asthma. We have standardised nasal allergen challenge as a useful tool to investigate the underlying mechanisms of hay fever and to enable collection of nasal fluid and/or brushings for the purpose of identifying novel biomarkers to monitor hay fever severity. Nasal allergen challenge also represents an alternative robust surrogate clinical readout of symptoms during natural seasonal grass pollen exposure for the purpose of clinical dose-ranging trials of novel treatments for hay fever. Nasal allergen challenge involves spraying small amounts of grass pollen into the nose and measuring symptom severity at 0-60 mins after challenge. In order for nasal allergen challenge to be a valid tool, it is essential that grass pollen extracts are available and standardised in terms of their concentration and stability in solution. We previously used an extract of Grass pollen, ‘Aquagen’. Unfortunately Aquagen has been discontinued, whereas the identical allergen source is now available in the form of a grass pollen lyophilisate tablet, (Grazax) that is available as an approved and licensed product for treatment of severe seasonal allergic rhinitis. Preliminary investigations have shown that Grazax tablets can be dissolved in saline to produce identical concentrations of allergen to Aquagen, with an identical stability profile in vitro. We therefore hypothesise that the clinical read out of nasal symptoms when using Grazax as the source of allergen extract for nasal challenge will be equivalent to that using Aquagen at corresponding allergen concentrations.
REC name
London - City & East Research Ethics Committee
REC reference
19/LO/1346
Date of REC Opinion
12 Aug 2019
REC opinion
Favourable Opinion