Intraocular penetration of trifluridine.

We studied intraocular penetration of topically applied trifluridine in five patients with herpetic keratitis undergoing penetrating keratoplasty. We compared the concentration of trifluridine and its metabolite 5-carboxy 2'-deoxyuridine in the aqueous humor to those of normal control patients undergoing routine cataract extraction without preoperative antiviral therapy. Significant concentrations of intact trifluridine were achieved in the acqueous humor after topical application of 1% trifluridine ophthalmic drops. The metabolite, 5-carboxy 2'-deoxyuridine, was not found in the aqueous humor. Unlike idoxuridine and vidarabine, it is possible to achieve therapeutic levels of trifluridine at intraocular sites that would be advantageous in the treatment of deep herpetic disease involving the stroma and iris.