Prostaglandin A2

New Zealand White rabbits (2.3 to 2.7 kg, free of preexisting corneal defects)^[3]

0.5 mg/mL; 1.0 mg/mL; 2.0 mg/mL

topical eyedrops; five doses per day every 2 hours; days 3 to 7 post-infection

Showed only one significant epithelial lesion score reduction vs.
placebo at a single dose and time point; overall, epithelial disease did not respond in a dose-dependent manner.
Recorded mean lesion scores on day 8 post-infection of 1.7 (1 mg/mL) and 2.1 (2 mg/mL).
Observed no significant differences in corneal thickness between treated and placebo groups at peak stromal involvement (12 to 14 days post-infection), with mean corneal thicknesses at day 12 post-infection of 473 ± 23 μm (0.5 mg/mL), 582 ± 76 μm (1.0 mg/mL), and 541 ± 42 μm (2.0 mg/mL).
Detected significantly higher anterior chamber flare scores in treated groups vs.
placebo in a dose-dependent manner, with mean flare scores after 1 day of therapy of 0.44 (0.5 mg/mL), 0.88 (1 mg/mL), and 1.03 (2 mg/mL).
Caused worse long-term sequelae in treated rabbits, with mean corneal thickness at 67 days post-infection of 569 ± 120 μm (1 mg/mL) and 694 ± 124 μm (2 mg/mL) vs.
480 ± 70 μm for placebo, and 14 of 28 treated eyes developing necrotizing stromal keratitis vs.
3 of 10 placebo eyes.
Observed no differences in virus recovery from trigeminal ganglia or corneas between treated and placebo groups, with 15 of 18 trigeminal ganglia from treated rabbits yielding infectious virus upon cocultivation, and 4 of 18 or 5 of 12 corneas from treated rabbits yielding infectious virus.