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.