Corneal Penetration into Rabbit Aqueous Humor Is Comparable between Preserved and Preservative-Free Tafluprost

Abstract

Background: Some studies have shown that benzalkonium chloride (BAK), a preservative used in antiglaucoma medications, can increase corneal permeability by acting as a penetration enhancer. Tafluprost is a new prostaglandin F₂_α analog in clinical use for the treatment of ocular hypertension and glaucoma. Methods: This study evaluated the corneal penetration of preservative-free tafluprost 0.0015% eye drops and tafluprost 0.0015% eye drops preserved with 0.01% BAK into the aqueous humor of rabbits. Results: After the administration of a single topical dose (30 μl), the maximum concentrations at 45 min of tafluprost acid in aqueous humor were 4.50 ng/ml for preservative-free tafluprost and 3.99 ng/ml for preserved tafluprost. The area under the concentration-time curves from 45 min to 3 h was 5.14 ng h/ml for the preservative-free formulation and 4.54 ng h/ml for the preserved formulation. Conclusions: These data indicate that BAK does not affect the corneal penetration of tafluprost into the rabbit aqueous humor.

Comparison of the efficacy and tolerability of preservative-free and preservative-containing formulations of the dorzolamide/timolol fixed combination (COSOPT™) in patients with elevated intraocular pressure in a randomized clinical trial

“…It has been suggested that the preservative benzalkonium chloride may be an important factor for drug penetration, and may improve the effectiveness of PC glaucoma drugs [18,19]. However, other data have not supported this hypothesis [20]. Our study showed that both PF and PC dorzolamide/timolol were equally effective in lowering IOP, and there was no evidence that the addition of benzalkonium chloride provided additional efficacy.…”

A novel in vivo corneal trans-epithelial electrical resistance measurement device

“…In vitro experimental systems using cultured cells are often employed to evaluate the barrier function of the corneal epithelium as well as injuries of the corneal epithelium caused by various drugs (Fukuda and Sasaki, 2012: Pellinen and Lokkila, 2009: Yee et al, 2006. These experimental systems provide an excellent means for the objective comparison of the potential for cornea injury among several ophthalmic solutions; however, the extent to which these experimental models reflect the condition of the eyes in vivo remains unclear (Denoyer et al, 2008).…”

Tafluprost/Timolol: A Review in Open-Angle Glaucoma or Ocular Hypertension

“…Of note, the corneal penetration of tafluprost into the aqueous humour of rabbits following a single dose of preservativefree tafluprost 0.0015 % was generally similar to that after a single dose of preservative-containing tafluprost 0.0015 % [15]. Following ocular instillation, timolol is absorbed through the cornea, with its corneal penetration slightly less following a single dose of tafluprost/timolol than following a single dose of timolol alone in rabbits [6].…”