NCT01147159

Brief Summary

Allergen extracts are complex mixtures of proteins and contain varying amounts of allergenic and non-allergenic components. Many factors such as the biovariability, differences in extraction process and subsequent handling of allergens can affect the final composition, potency, and stability of allergen preparations. Genetic diversity of affected people adds another level of complexity. In order to control variability and to achieve consistency and reproducibility for optimal safety and sensitivity/specificity, it is essential to standardize the amount of allergen used in prick tests. Therefore, the system for biological standardization mainly used in Europe still is the biological calibration of in-House Reference Preparations (IHRP). The method has been adopted by the Nordic Council on Medicines as the Nordic Biological Unit, Histamine Equivalent Potency (HEP) or Skin Prick Test (SPT) value. The aim of this procedure is to estimate the biological activity of allergen extracts. The activity of an allergen extract is defined as 10,000 Diagnostic Biological Units (DBU) per ml (1 SPT per ml), when the extract provokes a specific skin reaction with a wheal of the same size as a wheal provoked by reference histamine at a concentration of 10 mg/ml, when both solutions are administrated using the same technique (prick testing) on at least 20 individuals who are clinically allergic and cutaneously reactive to the allergen concerned. The present study aims to standardize the allergen extracts of Betula pendula, Phleum pratense and Dermatophagoides pteronyssinus by using this method.

  • Trial with medicinal product

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
68

participants targeted

Target at P50-P75 for phase_2

Timeline
Completed

Started Dec 2010

Shorter than P25 for phase_2

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

May 25, 2010

Completed
28 days until next milestone

First Posted

Study publicly available on registry

June 22, 2010

Completed
5 months until next milestone

Study Start

First participant enrolled

December 1, 2010

Completed
4 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 1, 2011

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

April 1, 2011

Completed
Last Updated

May 2, 2017

Status Verified

April 1, 2017

Enrollment Period

4 months

First QC Date

May 25, 2010

Last Update Submit

April 28, 2017

Conditions

Outcome Measures

Primary Outcomes (1)

  • Wheal size area

    The primary efficacy variable will be the wheal size area of the immediate phase reaction in mm2

    15 minutes after skin prick test

Study Arms (1)

Skin Prick Test

OTHER
Other: Extracts of allergens

Interventions

Skin prick test of extracts of allergens in 4 tenfold dilutions. Assessment wheal size after 15 minutes

Skin Prick Test

Eligibility Criteria

Age18 Years - 60 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Positive clinical history with inhalant allergy to at least one of the allergen to be standardized.
  • At least one positive prick test (mean wheal diameter = 3mm) when tested with already standardized extracts of the allergens under investigation.
  • Positive prick test (wheal diameter =3 mm) to Histamine 10 mg/ml
  • Age: 18-60 years
  • Written informed consent

You may not qualify if:

  • Diseases or medications, influencing the skin tests or that contradict the correct conduct and evaluation of the study.
  • Pregnancy, skin irritations, drug and alcohol abuse and participation in another clinical trial within the last 30 days

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Zentrum für klinische Forschung Clinical Trials Center, University Hospital and University Zurich

Zurich, CH-8091, Switzerland

Location

MeSH Terms

Conditions

Hypersensitivity

Condition Hierarchy (Ancestors)

Immune System Diseases

Study Officials

  • 01 Studienregister MasterAdmins

    UniversitaetsSpital Zuerich

    STUDY DIRECTOR

Study Design

Study Type
interventional
Phase
phase 2
Allocation
NA
Masking
NONE
Purpose
DIAGNOSTIC
Intervention Model
SINGLE GROUP
Model Details: Skin prick test of extracts of allergens in 4 tenfold dilutions.
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 25, 2010

First Posted

June 22, 2010

Study Start

December 1, 2010

Primary Completion

April 1, 2011

Study Completion

April 1, 2011

Last Updated

May 2, 2017

Record last verified: 2017-04

Locations