Feline herpes virus 1 (FHV-1) is a frequent cause of eye infections in cats. However, the drugs available to treat these infections must be applied multiple times a day and there is scant scientific evidence to support their use. A new model hopes to change that.

Researchers from the Baker Institute for Animal Health at Cornell University’s College of Veterinary Medicine (Cornell Vet Med) have developed a model system that can be used to test drugs for treating FHV-1. Early results have also pointed to a new drug that will soon head to clinical trials.

The study was published in the June issue of the Journal of General Virology.

The researchers filled corneas from cats that died of causes other than eye disease with agarose. Agarose enabled the corneas, which have the consistency of Jell-O, to maintain the natural, dome-shaped structures. After the corneas firmed up, the researchers turned them over and kept them in a liquid medium.

To use these petri plate corneas as a model of FHV-1 infection, the researchers then applied the virus to some of the corneas and left others uninfected. They then tested the effectiveness of two drugs that are used for topical treatment of FHV-1 eye infections in cats: cidofovir, which is frequently used in the clinic at Cornell Vet Med, and acyclovir, which has shown promise when given frequently.

Both drugs cleared the infection when applied every 12 hours, but cidofovir was more effective.

Additionally, the researchers used the model system to identify another drug for treating FHV-1 infections. The antiretroviral drug raltegravir, commonly used in humans to treat HIV infections, had never been used to treat FHV-1 in cats before.

“We found that it is very effective against FHV-1,” said Gerlinda R. Van de Walle, DVM, PhD, and one of the study authors. “It even worked when we applied the drug only once every 24 hours.”

Photo credit: © iStock/rkankaro