The Effects of Xalatan ® On the Recovery of Ocular Herpes Simplex Virus Type 1 (HSV-1) in the Induced Reactivation and Spontaneous Shedding Rabbit Models

Abstract

Purpose: Xalatan^® treatment has been reported both clinically and experimentally to promote recurrences of herpetic keratitis. Our goal was to determine the effects of topical Xalatan^® and its components on the recovery of ocular herpes simplex virus type 1 (HSV-1) in the Induced Reactivation (IR) and Spontaneous Shedding (SS) HSV-1/NZW rabbit latency models using virological outcome measures. Methods: HSV-1 latently-infected rabbits in both the IR and SS studies were divided into different topical treatment groups to evaluate commercial Xalatan^®, its preservatives, and vehicle against appropriate negative and positive controls. In the IR Studies, 91 rabbits received intra-stromal injections of water in both eyes to promote ocular shedding of latent HSV-1. All eyes were then treated and cultured for 10 days. In the SS Studies, 65 rabbits were treated and cultured in both eyes for 30 days. Results: Dexamethasone, a positive control, promoted extensive ocular shedding of HSV-1 in both the IR and SS Models. In general, neither Xalatan^® nor its components demonstrated any adverse effects, but some experimental variation was noted. All groups demonstrated comparable recovery of latent HSV-1 from respective trigeminal ganglia. Conclusions: Our experimental studies support the world wide clinical epidemiological experience that commercial Xalatan^® does not appear to promote HSV-1 ocular shedding.