Canine patient triumphs over cancer following clinical trial success
Lola, a 9-year-old golden retriever, was referred to UC Davis William R. Pritchard Veterinary Medical Teaching Hospital after she was diagnosed with oral melanoma
Lola, a 9-year-old golden retriever, was diagnosed with oral melanoma, which had already spread to her lungs in February 2023. At the time of her diagnosis, Allison Roth, Lola’s owner, was told by her veterinarian that Lola had less than 6 months to live, and referred her to the oncology service at the UC Davis William R. Pritchard Veterinary Medical Teaching Hospital for treatment options.
Lola, a 9-year-old golden retriever, was treated at UC Davis William R. Pritchard Veterinary Medical Teaching Hospital for an oral melanoma that spread to her lungs (Image courtesy of UC Davis College of Veterinary Medicine)
“When Lola was a puppy, I was treated for a brain tumor at the Mayo Clinic,” said Roth, in an organizational release.1 “Through my multiple brain surgeries, she was always by my side. When it came time for her cancer treatments, I was thrilled that she would be treated at UC Davis – what I would call the ‘Mayo Clinic for dogs.’”
After consulting with the specialists, Roth had to decide between 2 options for Lola. Either receive palliative radiation treatments that could give her more time or participate in a study at the school’s Veterinary Center for Clinical Trials. The trial was showing success for a new immunotherapy, and Roth decided to enroll Lola in the clinical trial.
The study at UC Davis, “Intravenous Doxorubicin and Inhaled IL-15 Immunotherapy for Treatment of Lung Metastases,” was the latest version of an ongoing series of clinical trials of immunotherapy treatments that involves inhaling cancer-fighting medication, according to an organizational release.1 Sponsored by the National Cancer Institute at the National Institutes of Health, the collaborative study was led by co-principal investors Robert Rebhun, DVM, PhD, Michael Kent, DVM, DACVIM (Oncology), DACVR (Radiation Oncology), and Robert Canter, MD.
The researchers for the study wanted to explore additional treatment options since previous iterations of the IL-15 clinical trials were demonstrating success. This study, which is the third version of the trial, enrolled 10 canine patients with pulmonary metastasis greater than 1 centimeter with a goal of determining whether preconditioning the immune system with chemotherapy improved the response rates to the inhaled IL-15 drugs.
“The previous trials we conducted found that inhaled IL-15 is well tolerated and resulted in durable responses in a subset of dogs with metastatic melanoma or osteosarcoma,” explained Rebhun.1 “We were excited to see if modulating the immune system with chemotherapy might improve response rates in patients with metastatic tumors to the lung.”
Lola receiving IL-15 treatment that required her to inhale cancer-fighting medication
X-rays of Lola’s lungs showed many spots prior to the trial and she did not tolerate the single dose of chemotherapy well to begin the trial, and x-rays following the inhalation treatments, which were 2 times a day for 2 weeks, were not better. The UC Davis team hoped for her x-rays to show either the same as pre-treatment or an elimination of some tumors, but Lola’s showed even more tumor growth. Because of this, she failed out of the trial twice, leading Roth to change her course of action to palliative radiation treatments. In May and June 2023, Lola received 2 treatments of radiation twice a week for 3 weeks.
The radiation treatments were able to shrink the tumor located in Lola’s mouth completely, but another x-ray showed continued tumor growth on her lungs following the radiation. Roth explained that they thought they would lose Lola in the summer of 2023, but she managed to hold on for the entire summer. Then, to the shock of Lola’s team and family, in September 2023, another x-ray showed all her tumors were gone. Researchers believed that she had experienced a delayed response to the IL-15 trial.
“In people, immunotherapies can sometimes result in inflammation of tumors, making them appear larger before they shrink,” Rebhun explained. “This is termed ‘pseudoprogression,’ and it appears to have happened with Lola.”
Two years later, Lola appears to be cancer-free and continues to receive regular checkups at UC Davis, and none of her tumors returned.
Reference
- Dog Beats Cancer Odds After Successful Completion of Clinical Trial. News release. April 23, 2025. Accessed April 28, 2025. https://www.vetmed.ucdavis.edu/news/dog-beats-cancer-odds-after-successful-completion-clinical-trial
