Evaluation of Safety, Tolerability, Immunogenicity and Efficacy of a Novel Method in Specific Immunotherapy in Cat Allergic Patients: a Placebo Controlled Trial

Inclusion criteria: * History and subjective symptoms of cat dander allergy including cat specific allergic rhinitis * Age 18 to 65 years * Positive reaction to at least one concentration of cat dander allergen in skin prick test, intradermal provocation test and nasal provocation test Exclusion criteria: * Chronic infectious disease * Acute infections * Episode of non-allergic rhinitis within the last 4 weeks * Use of allergen known to predict anaphylactic reactions * Treatment with any other investigational drug within 3 months before trial entry * Vaccination within the last week * Nasal surgery within the last 8 weeks * Progressive fatal disease * Drug or alcohol abuse within the last 5 years * Cat ownership * A history of significant cardiac insufficiency (NYHA stage III-IV) * Coexisting severe disease, e.g. cardiovascular diseases * Acute or history of obstructive respiratory insufficiency ( FEV1 \<70%) * Hepatic insufficiency * Relevant anaemia (as judged by investigator) * Blood donation within the last 30 days or intended blood donation (during the study or 30 days after participation) * Pregnancy or breast feeding * Sexually active woman of childbearing potential not actively practicing birth control by using a medically accepted device or therapy * Lack of compliance or other sililar reason, that the investigator believes, precludes satisfactory participation in the study * Systemic glucocorticoid therapy * Allergic asthma and chronic medication with steroids at doses exceeding 200ug/day Treatment with ATII antagonists, B-blocker, ACE inhibitors