Biological Standardization of Dactylis Glomerata Allergen Extract

Biological Standardization of Dactylis Glomerata Allergen Extract to Determine the Biological Activity in Histamine Equivalent Prick (HEP) Units

The objective of this study is to determine the biologic activity of a Dactylis glomerata allergen extract in histamine equivalent prick (HEP) units, in order to be used as in-house reference preparation (IHRP).

Study Overview

• Status: Completed
• Conditions: Allergy to Grass Pollen (Dactylis Glomerata)
• Intervention / Treatment: Biological: Four different concentrations of Dactylis glomerata allergen extract, positive control and negative control

Detailed Description

This is an open, unblinded and non-randomized biological assay. The study design is a slight modification of the recommendations proposed by the Nordic Guidelines.

Four concentrations of Dactylis glomerata allergen extract, together with a positive and negative control, using 10 mg/ml histamine dihydrochloride solution and a glycerinated phenol saline solution, respectively, will be tested in every patient in duplicate on the volar surface of the forearm.

• Study Type: Interventional
• Enrollment (Actual): 31
• Phase: Phase 2

Contacts and Locations

Study Locations

• Spain
  • Madrid / Madrid
    • Madrid, Madrid / Madrid, Spain, 28005
      • Hospital Universitario La Princesa
  • Sevilla / Andalucía
    • Sevilla, Sevilla / Andalucía, Spain, 41700
      • Hospital El Tomillar - Area Hospitalaria de Valme

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. A documented positive case history with inhalation allergy (rhinitis and/or rhinoconjunctivitis and/or asthma) related to Dactylis glomerata.
2. Subject has provided written informed consent, appropriately signed and dated by the subject (or legal representative, if applicable).
3. Subject can be male or female of any race and ethnic group.
4. Age > 18 years and < 50 years at the study inclusion day.
5. Positive skin prick test with a standardized commercially available preparation of Dactylis glomerata allergen extract. The skin prick test will be considered positive if the test results in a wheal major diameter of at least 3 mm and at least the size of the positive control. Positive skin prick test results are valid if performed within one year prior to the inclusion of the subject in the study
6. A positive test for specific IgE to Dactylis glomerata(CAP-RAST ≥ 2). IgE results are valid if performed within one year prior to the inclusion of the subject in the study.
7. Allergic symptoms during the pollen season of Dactylis glomerata.
8. Mean of the forearm major diameters of the wheals provoked by histamine dihydrochloride (10 mg/ml) ≥ 3 mm.

Exclusion Criteria:

1. Immunotherapy in the past 5 years with an allergen preparation known to interfere with the allergen to be tested (e.g., grass group extracts).
2. Use of drugs that may interfere with the skin reactions (e.g., antihistamines). See Appendix 1
3. Treatment with any of the following medications: tricyclic or tetracyclic antidepressants, β-blockers or corticosteroids (> 10 mg/day of prednisone or equivalent).
4. Pregnancy.
5. Dermographism affecting the skin area at the test site at either study visit.
6. Atopic dermatitis affecting the skin area at the test site at either study visit.
7. Urticaria affecting the skin area at the test site at either study visit.
8. Participation in another clinical trial within the last month.
9. Subjects suffering from pathologies or conditions in which adrenalin is contraindicated (heart disease, severe hypertension,..)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 1; Dactylis glomerata allergen extract at 4 different concentrations; Positive control; Negative control	Biological: Four different concentrations of Dactylis glomerata allergen extract, positive control and negative control; Four concentrations of Dactylis glomerata allergen extract, together with a positive and negative control will be tested in every patient in duplicate on the volar surface of the forearm.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Wheal size area (mm2) on the skin at the site of the puncture during the immediate phase.	Test sites should be inspected and recorded 15-20 min after application

Collaborators and Investigators

• Sponsor: Laboratorios Leti, S.L.

Study record dates

Study Major Dates

• Study Start: October 1, 2011
• Primary Completion (Actual): March 1, 2012
• Study Completion (Actual): June 1, 2012

Study Registration Dates

• First Submitted: August 1, 2011
• First Submitted That Met QC Criteria: August 1, 2011
• First Posted (Estimate): August 2, 2011

Study Record Updates

• Last Update Posted (Estimate): August 9, 2012
• Last Update Submitted That Met QC Criteria: August 8, 2012
• Last Verified: August 1, 2012

More Information

Terms related to this study

• Keywords: Immunotherapy; Skin prick test; Standardization; Dactylis glomerata
• Other Study ID Numbers: 6038-PR-PRI-181; 2010-023948-33 (EudraCT Number)