Pharmacodynamic Clinical Trail of Recombinant Human Hyaluronidase Assisted Subcutaneous Infusion in Healthy Volunteers

Hyaluronic acid (HA) is an acidic mucopolysaccharide widely found in connective tissues such as the intercellular matrix of human tissues, the vitreous humour of the eye and the synovial fluid of the joints, and is a component of the tissue matrix that acts to restrict the diffusion of water and other extracellular substances. Its gel-like nature makes it a barrier to subcutaneous fluid diffusion and is an important limitation to subcutaneous infusion. It has also been reported in the literature that lymph nodes, liver and skin are the major metabolic sites of HA, with a metabolic half-life in the skin of approximately 15-20 h. This means that the structure of HA destroyed by enzymatic cleavage can be autonomously rebuilt within 24-48 h. The rapid metabolism characteristics of HA make it an ideal target for action. Hyaluronidase (EC 3.2.1.35), or hyaluronidase, is an endoglycosidase capable of degrading and oligomerising HA. HAase hydrolyses the β-1,4 glycosidic linkage in the HA chain to yield small molecules of HA or oligosaccharides, thereby increasing tissue permeability and improving the permeability of tissues to fluids. HAase has been used in the medical field for many years as a drug diffusing agent, which can promote the diffusion of locally stored drugs, exudate or blood, accelerate the absorption of drugs, reduce local tissue tension and pain, and facilitate the absorption and drainage of oedema and inflammatory exudate. Clinically, HAase is used clinically as an adjunct to subcutaneous infusion.