Effect of holoBLG on Cat Allergic Patients

Inclusion Criteria: * At least 1 year of clinically relevant cat allergy * positive SPT (wheal \>3mm) * Positive NPT * Increase in TSS \>3 during the 1st exposure in the AEC * Verbal and written consent Exclusion Criteria: * subjects \<18 years * subjects taking immunosuppressive drugs such as systemic corticosteroids, cyclosporine, etc. * subjects who have received or are currently receiving sublingual or subcutaneous immunotherapy (SLIT/SCIT) for cat allergy in the last 2 years prior to V0 * clinically relevant overreactions to the ingredients of holoBLG, in particular subjects with a milk protein allergy or pronounced lactose intolerance * subjects with severe asthma and/or a history of uncontrolled asthmatic attacks in the last three months before the selection process (GINA 4 and 5). * subjects with an FEV1 \<70% (predicted value) prior to exposure in the AEC * Lack of verbal and written informed consent * subjects who are not proficient in the German language * History of serious chronic medical illness and/or any condition for which the local investigator believes that participation in the study could pose a risk to the individual * Pregnancy and lactation * Contraindications and/or history of adrenaline intolerance and/or emergency medications * Concurrent use of anti-allergic medications and/or inadequate washout period of these anti-allergic medications prior to the selection process and exposure in the exposure chamber * TSS ≥ 6 at t0 of first exposure in the AEC * Subjects who have a history of ingestion of holoBLG