Factors Predicting Efficacy of Allergen Injection Immunotherapy for Grass Pollen Hayfever
Rhinitis, Allergic, Seasonal
Biological: Sublingual Alutard SQ grass pollen tablets (Phleum pratense)
Procedure: Venepuncture: 100ml blood sample taken on 12 separate visits
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Primary Purpose: Treatment
|Official Title:||Factors Predicting Efficacy of Allergen Injection Immunotherapy for Grass Pollen Hayfever: A Pilot Study. (Up-dosing Study)|
- Symptom and medication score recorded by subjects
- Adverse events
- Rhinoconjunctivitis Quality of Life Questionnaire
- Intradermal allergen challenge
|Study Start Date:||October 2002|
|Estimated Study Completion Date:||February 2004|
This was a single centre, randomised, double-blind placebo controlled trial of grass pollen injection immunotherapy (Alutard SQ, ALK Abello, Denmark) in adults with severe summer hayfever unresponsive to antihistamines and topical steroids. The main aim was to determine at which point in the dosing regime grass pollen immunotherapy causes a significant reduction in the late skin response to allergen challenge. A once weekly cluster regimen of 2 injections per visit was employed during the up-dosing phase, followed by monthly maintenance injections of 100,000 SQ units. Twelve patients received active treatment (mean age 31, 7 male) whilst 6 were given placebo (mean age 37, 2 male). The 24 hour skin response (size of swelling, (mm)) to intradermal allergen challenge (0.1, 1, 10 BU) was determined on alternate weeks during the 8 week up-dosing phase and then monthly up to 6 months and 3 monthly up to 11-13 months following initiation of treatment.
At the end of the up-dosing phase (approximately 8 weeks) there was a significant reduction in the size of the late phase response which was evident with all three intradermal doses (p=0.02 for 0.1 & 1 BU and p=0.04 for 10 BU). This reduction was sustained throughout the maintenance phase (p=0.04 for 0.1 BU and 0.01 for 1& 10BU).
The up-dosing phase of grass pollen immunotherapy alone is sufficient to dampen the late skin response to allergen challenge. Whether or not this may be predictive of the clinical response to immunotherapy remains to be determined.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00135629
|Royal Brompton Hospital, NHLI Imperial College|
|London, United Kingdom, SW3 6LY|
|Principal Investigator:||Stephen R Durham, Professor||Royal Brompton Hospital, Imperial College, National Heart & Lung Institute|