Hialid Mechanism of Action

Pharmacology: Mechanism of action: Sodium hyaluronate binds to fibronectin. The action is considered to accelerate the adhesion and migration of corneal epithelial cells. Sodium hyaluronate also has an excellent water-retentive property because each sodium hyaluronate molecule can retain many H₂O molecules.
Acceleration of corneal wound healing: When 0.1% - 0.5% ophthalmic solutions of sodium hyaluronate were instilled in rabbit wound models with corneal epithelium and corneal epithelial basement membrane detached, the wounded area decreased significantly compared to vehicle ophthalmic solution from 24 hours post-detachment and onwards.
Acceleration of corneal epithelial migration: In isolated strips of cultured rabbit cornea, sodium hyaluronate significantly accelerated the migration of corneal epithelial layer compared to the control group (with culture medium only) (in vitro).
Water retentive property: When 0.1% - 1.0% sodium hyaluronate solutions were dropped onto agar plugs, weight loss of agar plugs due to water evaporation was prevented in a concentration-dependent manner (in vitro).
Clinical studies: The following tables show effectiveness rate of the product in clinical studies including double-blind studies conducted on patients with keratoconjunctival epithelial disorder resulting from sicca syndrome (dry eye), Sjögren's syndrome, contact lens wearing, etc.
0.1% w/v ophthalmic solution: See Table 3.

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0.3% w/v ophthalmic solution: See Table 4.

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Pharmacokinetics: Serum concentration: Serum concentrations of hyaluronic acid were determined before topical application as well as on treatment day 3, day 9 (the last day of dosing), and day 10 in 6 healthy adult male volunteers. To the unilateral eye of the subjects, 0.1% (day 1) and 0.5% (days 2-9) ophthalmic solutions of sodium hyaluronate were instilled at a dose of one drop 5 times daily (days 1-2) and one drop 13 times daily (days 3-9). All serum concentrations determined before, during, and after treatment were less than the limit of quantitation (10 μg/ml).
Approved concentrations of these products are 0.1% and 0.3%.
Intraocular distribution in animals (reference: rabbits): Following a single topical application of 50 μl of 0.1% ¹⁴C-sodium hyaluronate ophthalmic solution in rabbits with a normal cornea, high levels of radioactivity were detected in the outer ocular area (bulbar conjunctiva, extraocular muscles and sclera). Especially in the bulbar conjunctiva, the radioactivity was detected until 8 hours after application. In contrast, the radioactivity level in the cornea was slightly detected 0.5 hours after application.
Following topical application of 50 μl of 0.1% ¹⁴C-sodium hyaluronate ophthalmic solution in rabbits with corneal epithelium wound, high levels of radioactivity were detected in the cornea and aqueous humor even 1 hour after application.