Zoster Eye Disease Study (ZEDS): A multi-center, randomized, double-masked, placebo-controlled clinical trial of valacyclovir for one year in immunocompetent study participants with an episode of dendriform epithelial keratitis, stromal keratitis, endothe

The purpose of this study is to find out whether one year of a low dose of the medicine valacyclovir reduces complications of shingles affecting the eye. Shingles is caused by the chicken pox virus. Patients are asked to participate in this study because they have eye problems due to shingles. The study will involve two groups of participants. One group will receive daily valacyclovir medication and the other group will receive placebo (a pill designed to look like valacyclovir but contains no active drug). This study is looking to see if treatment with 12 months of daily valacyclovir medication reduces the development of certain types of new or worsening eye disease; specifically, infection on the surface of the front of the eye (cornea), inflammation of the cornea, or inflammation inside the front of the eye (referred to as dendriform epithelial keratitis, stromal keratitis, endothelial keratitis, and iritis). This study also hopes to find out if this treatment reduces postherpetic neuralgia, the condition of ongoing pain after the shingles infection goes away. In addition, the study wants to find out if the effects of valacyclovir treatment last during the six months after treatment is finished. This trial is a NIH defined Phase 3 (FDA defined Phase 4)