Oral administration of Factor VIII in lipid vesicles

The prevention or treatment of severe bleedings in patients with haemophilia A presently depends on intravenous administration of partially purified preparations of the missing coagulation Factor VIII. In spite of the revolutionary breakthrough that came in the treatment of haemophiliacs with the introduction of suitable Factor VIII preparations for clinical use, this therapy still presents a variety of problems, not the least of them being the recurrent injections themselves. Oral administration of these Factor VIII preparations is useless due to extensive degradation of the protein in the gastrointestinal tract. This breakdown may be overcome to a certain extent if the protein is packed in liposomes, which may decrease exposure to the digestive proteolytic enzymes. It has been reported that liposome entrapped proteins are capable of entering intact cells1, and insulin loaded liposomes administered orally to diabetic rats can cause a fall in the blood glucose level2.