New Cancer Drug Offers Hope for Cats and Humans Alike
Jakiro, or “Jak,” a 9-year-old black domestic shorthair, naps in a sunbeam on a quiet afternoon. To his owner, Tina Thomas, every extra moment with Jak feels precious. Diagnosed with oral squamous cell carcinoma—a devastating and aggressive cancer in cats—Jak was expected to live only six to eight weeks. Instead, he survived more than eight months, thanks to a groundbreaking clinical trial testing a new cancer drug at the University of California, San Francisco (UCSF) and UC Davis.
The trial, the first of its kind in pet cats, showed that 35 percent of cats with squamous cell carcinoma had their disease controlled with minimal side effects. Oral squamous cell carcinoma in cats is notoriously difficult to treat, with traditional therapies such as surgery, chemotherapy, and radiation offering little hope. “One of the struggles I’ve had my entire career is that cats with this cancer—there is really nothing we can do,” said Katherine Skorupski, a professor of clinical medical oncology at UC Davis. “So the fact that we would have something, anything, that might help these cats is so exciting.”
The drug, originally developed for human head and neck cancers, targets a protein called STAT3—a molecular switch that drives cancer cell growth. “What’s exciting is that this study shows it’s possible to shut down a protein that drives cancer,” said Daniel Johnson of UCSF’s Helen Diller Family Comprehensive Cancer Center. Researchers also noted that cats with naturally occurring cancers can serve as better models for human disease than traditional mouse studies, potentially accelerating cancer research for people.
Jak’s story illustrates the human and veterinary impact of the trial. After receiving weekly treatments for a month, his symptoms improved, allowing him to enjoy more quality time with his family, including one more Christmas under the tree. “It was invaluable to us to give him time where he was comfortable and could enjoy being around his family,” Thomas said.
Across the 20 cats enrolled in the trial, seven experienced partial responses or stable disease. Apart from mild anemia, none developed significant side effects. The treatment not only blocked STAT3 but also appeared to boost proteins linked to immune responses against cancer.
Jennifer Grandis of UCSF emphasized the broader implications: “By partnering with veterinary oncologists and doing clinical trials in companion animals, we can learn an enormous amount about how these drugs work while also helping people’s pets. None of the cats in these trials were harmed, and many of them benefited.”
The research team, including UC Davis collaborators Robert Rebhun, Daniel York, Hong Chang, and Ellen Sparger, is now working with a biotech company to advance the compound in clinical trials for both cats and humans. Funded by the National Institutes of Health and the UC Davis Center for Companion Animal Health, this study may represent a turning point in feline cancer care—and a potential breakthrough for human oncology.
