Collagen shield delivery of trifluorothymidine

Area of Science:

• Ophthalmology
• Pharmacology
• Drug Delivery Systems

Background:

• Herpetic keratouveitis requires effective antiviral drug delivery to the cornea and aqueous humor.
• Trifluorothymidine (F3T) is an antiviral agent used in ophthalmic treatments.
• Optimizing drug penetration is crucial for therapeutic efficacy.

Purpose of the Study:

• To evaluate the impact of collagen shields on corneal and aqueous humor penetration of trifluorothymidine (F3T).
• To compare F3T levels with and without collagen shields in normal and damaged rabbit eyes.
• To assess the potential of collagen shields to enhance F3T delivery for ophthalmic infections.

Main Methods:

• Rabbit eyes with and without epithelial defects were used.
• Trifluorothymidine (F3T) was applied topically, with or without collagen shields presoaked in F3T.
• Corneal and aqueous F3T concentrations were measured at multiple time points (30 minutes, 2, 4, and 8 hours).

Main Results:

• In eyes with epithelial defects, collagen shields significantly increased F3T levels in the cornea and aqueous humor compared to drops alone.
• A presoaked shield alone also showed higher F3T levels than drops alone at early time points (30 minutes, 2 hours).
• Collagen shields did not enhance F3T penetration in eyes with intact corneal epithelium.

Conclusions:

• Collagen shields can significantly enhance the ocular penetration of trifluorothymidine (F3T) in the presence of corneal epithelial damage.
• This drug delivery enhancement may improve treatment outcomes for conditions like herpetic keratouveitis.
• The use of collagen shields is beneficial only when the corneal epithelium is compromised.