To test the nasal biological availability of the BioBlock® immunoglobulin preparation, 16 healthy volunteers were recruited in the phase 0 clinical trial. The study was conducted in the premises of the Ear Clinic of Tartu University Hospital. The study protocol was approved by Research Ethics Committee of the University of Tartu on March 17, 2021 (No 336/T-1). Written informed consent in accordance with the Declaration of Helsinki was obtained from each healthy volunteer. The study group was divided into two subgroups where the individuals were intranasally administered into both nostrils of BioBlock® formulation which contained either 0.1 mg/mL or 0.2 mg/mL of the colostrum immunoglobulin preparation (n=8 in both study groups). A filter paper with a volume capacity of 15 µL was placed on the medial nasal surface using surgical forceps and it was kept on nasal mucosa for 10 minutes. Following this the BioBlock was administered to the nasal cavity. The nasal mucosal sampling was done at 4 timepoints. The samples were analyzed using a Cow IgG ELISA kit.
