Ac₂IDU, BVDU, and Thymine Arabinoside Therapy in Experimental Herpes Keratitis

The therapeutic efficacy of three new antiviral agents—5-iodo-3',5'-diacetyl-2-deoxyuridine (diacetylidoxuridine, 1% Ac₂IDU), E-5-(2-bromovinyl)-2'-deoxyuridine (0.25% BVDU), and 3% thymine arabinoside—is compared with available antivirals in an experimental model of herpes simplex virus type 1 (HSV-1) keratitis in New Zealand white rabbits. Compared with placebo, Ac₂IDU significantly reduced ulcerative keratitis on days 4 through 8 after inoculation with virus and iritis on day 8 after inoculation. Compared with placebo, thymine arabinoside reduced ulcerative keratitis but not significantly. Thymine arabinoside caused significant iritis in all eyes. The epithelial disease in BVDU-treated eyes was significantly less than that in placebo-treated eyes on days 5 through 8 after inoculation. The results indicate that 1% Ac₂ IDU and 0.25% BVDU were effective in our ocular model of HSV-1 keratitis, whereas thymine arabinoside was not.