Suppression of ocular herpes recurrences by a thymidine kinase inhibitor in squirrel monkeys

5′-Ethynylthymidine, an inhibitor of viral thymidine kinase (TK), was given intraperitoneally to squirrel monkeys previously infected by the ocular route with Rodanus strain herpes simplex virus. Spontaneous ocular recurrences were reduced during therapy, compared to saline-treated controls. This is the first in vivo demonstration that a viral TK inhibitor can reduce recurrences of HSV-1. Similar benefit would be expected for HSV-2 and perhaps VZV (varicella zoster virus).