Jack Hoopes spends a lot of time with dying dogs. A veterinary radiation specialist at Dartmouth College, Hoopes has spent his decades-long career treating canine cancers with the latest experimental therapies as a pathway for developing human treatments. Recently, many of Hoopes’ furry patients have come to him with a relatively common oral cancer that will almost certainly kill them within a few months if left untreated. Even if the cancer goes into remission after radiation treatment, there’s a very high chance it will soon re-emerge.

For Hoopes, it’s a grim prognosis that’s all too familiar. But these pups are in luck. They’re patients in an experimental study exploring the efficacy of a new cancer treatment derived from a common plant virus. After receiving the viral therapy, several of the dogs had their tumors disappear entirely and lived into old age without recurring cancer. Given that around 85 percent of dogs with oral cancer will develop a new tumor within a year of radiation therapy, the results were striking. The treatment, Hoopes felt, had the potential to be a breakthrough that could save lives, both human and canine.

“If a treatment works in dog cancer, it has a very good chance of working, at some level, in human patients,” says Hoopes.