Effectiveness of Cat-PAD to Treat Cat Allergy in Cat Allergic Subjects

A Double-Blind, Randomised, Placebo-Controlled Study to Evaluate the Efficacy of Cat-PAD in Cat Allergic Subjects Following Challenge to Cat Allergen in an Environmental Exposure Chamber.

Cat allergy is an increasingly prevalent condition, affecting 10-15% of patients with allergic rhinoconjunctivitis and/or asthma. Cat-PAD is a novel, synthetic, allergen-derived peptide desensitising vaccine, currently being developed for the treatment of cat allergy. This study will investigate the efficacy of 4 treatment regimens of Cat-PAD in cat allergic subjects following challenge to cat allergen in an environmental exposure chamber (EEC).

Study Overview

• Status: Completed
• Conditions: Cat Allergy
• Intervention / Treatment: Biological: Cat-PAD; Biological: Cat-PAD; Biological: Cat-PAD; Biological: Cat-PAD; Biological: Cat-PAD

Detailed Description

This study is designed as a multicentre, randomised, double-blind, placebo-controlled study of 4 treatment regimens in up to 120 cat allergic subjects. A total of 24 subjects will be randomised into each treatment group. Each subject will undergo screening up to 4 weeks before treatment. Baseline challenge will consist of exposure to cat allergen for 3 hours in an EEC on 4 visits on successive days a week before the first administration of Cat-PAD or placebo. Treatment will be administered as intradermal injections into the flexor surface of alternate forearms. There are 5 treatment regimens involving administration of Cat-PAD or placebo. Post-treatment challenge (PTC) will consist of exposure to cat allergen for 3 hours in an EEC on 4 visits on successive days 18 weeks after the first administration of study medication.

• Study Type: Interventional
• Enrollment (Anticipated): 120
• Phase: Phase 2

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, L4W 1N2
      • Cetero Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Minimum 1-year documented history of rhinoconjunctivitis (Nasal symptoms: sneezing, itching, rhinorrhoea, blockage; Ocular symptoms: itching, redness, soreness, watering) on exposure to cats. [Subjects may also have controlled asthma (GINA classification 1)].
• Positive skin prick test to cat allergen with a wheal diameter at least 3mm larger than that produced by the negative control.
• Subjects must achieve minimum qualifying symptom scores on at least one Symptom Diary Card during EEC exposure on the third and fourth day during the Baseline Challenge. Minimum qualifying symptom scores are defined as a TRSS of at least 10 out of a possible 24 and a TNSS of at least 6 out of a possible 12.

Exclusion Criteria:

• Subjects with asthma falling under GINA classification 2 (partly controlled) and 3 (uncontrolled).
• A history of anaphylaxis to cat allergen.
• Subjects with a cat specific IgE >100 kU/L.
• Subjects with an FEV1 <80% of predicted.
• Subjects with an acute phase skin response to cat allergen with a mean wheal diameter > 50mm.
• Subjects who suffer from seasonal allergic rhinoconjunctivitis, and cannot complete the clinical study outside the local pollen season or who have significant allergy to other animal dander that cannot be avoided during the study period.
• Subjects who cannot tolerate baseline challenge in the EEC.
• Allergen immunotherapy during the last 12 months or any history of Cat Dander immunotherapy.
• Subjects for whom administration of adrenaline is contra-indicated (e.g. subjects with acute or chronic symptomatic coronary heart disease or severe hypertension).
• Subjects being treated with beta-blockers.
• History of immunopathological diseases.
• Positive test for Hepatitis B, Hepatitis C or HIV at screening.
• Have a history of severe drug allergy or anaphylactic reaction to food.
• A known allergy to thioglycerol.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 1	Biological: Cat-PAD; Cat-PAD dose 2X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 4 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 8 administrations 2 weeks apart; Biological: Cat-PAD; Placebo
Experimental: 2	Biological: Cat-PAD; Cat-PAD dose 2X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 4 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 8 administrations 2 weeks apart; Biological: Cat-PAD; Placebo
Experimental: 3	Biological: Cat-PAD; Cat-PAD dose 2X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 4 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 8 administrations 2 weeks apart; Biological: Cat-PAD; Placebo
Experimental: 4	Biological: Cat-PAD; Cat-PAD dose 2X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 4 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 8 administrations 2 weeks apart; Biological: Cat-PAD; Placebo
Placebo Comparator: 5	Biological: Cat-PAD; Cat-PAD dose 2X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 2 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 4 administrations 4 weeks apart; Biological: Cat-PAD; Cat-PAD dose 1X 8 administrations 2 weeks apart; Biological: Cat-PAD; Placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Change from baseline in Total Rhinoconjunctivitis Symptom Score (TRSS) using all timepoints during PTC in Cat-PAD treatment groups compared to placebo.	18 weeks

Secondary Outcome Measures

Outcome Measure	Time Frame
Change from baseline in TRSS in Cat-PAD treatment groups at last two timepoints on third and fourth challenge days compared to placebo.	18 weeks
Change from baseline in individual symptom scores for ocular and nasal symptoms at all timepoints during Exposure Chamber visit in Cat-PAD treatment groups compared to placebo.	18 weeks
Change from baseline in TRSS at all timepoints during Exposure Chamber visit in pooled data from Cat-PAD treatment groups compared to placebo.	18 weeks
Proportion of subjects prematurely leaving the EEC due to intolerable symptoms during Post-Treatment Challenge (PTC) in Cat-PAD treatment groups compared to placebo.	18 weeks
Change from baseline in EEC-Rhinoconjunctivitis Quality of Life Questionnaire (EEC-RQOL) at all timepoints during Exposure Chamber visit in Cat-PAD treatment groups compared to placebo.	18 weeks
Exploratory analyses of change from baseline in asthma symptoms, FEV1 and use of rescue medication in Cat-PAD treatment groups compared to placebo in asthmatic subjects.	18 weeks

Collaborators and Investigators

• Sponsor: Circassia Limited
• Investigators: Principal Investigator: Deepen Patel, MD, Allied Research International Inc-Cetero Research

Study record dates

Study Major Dates

• Study Start: August 1, 2008
• Primary Completion (Actual): April 1, 2009
• Study Completion (Actual): May 1, 2009

Study Registration Dates

• First Submitted: August 4, 2008
• First Submitted That Met QC Criteria: August 4, 2008
• First Posted (Estimate): August 7, 2008

Study Record Updates

• Last Update Posted (Estimate): July 8, 2009
• Last Update Submitted That Met QC Criteria: July 7, 2009
• Last Verified: July 1, 2009

More Information

Terms related to this study

• Keywords: Immunotherapy; Cat allergy; Cat-PAD; Environmental Exposure Chamber
• Additional Relevant MeSH Terms: Immune System Diseases; Hypersensitivity
• Other Study ID Numbers: CP002