Penn Researchers Demonstrate Efficacy Of Non-Hodgkin's Lymphoma Vaccine

An experimental vaccine developed by researchers at the University of Pennsylvania's schools of Medicine and Veterinary Medicine is the first veterinary cancer vaccine of its kind that shows an increase in survival time for dogs with spontaneous non-Hodgkin's lymphoma. The work shows for the first time the feasibility and therapeutic efficacy of this alternative cell-based vaccine, which could be employed in the treatment of a number of different cancer types. The research was conducted by Nicola Mason, assistant professor of medicine at Penn Vet; Robert H. Vonderheide, associate professor of hematology and oncology at the Perelman School of Medicine; and Karin U. Sorenmo, associate professor of oncology at Penn Vet. Erika Krick, Beth Overley and Thomas P. Gregor of Penn Vet and Christina M. Coughlin of the School of Medicine also contributed to the research.

Their work was published in the open access journal PLOS ONE.

The team recruited dogs that were brought to Penn's Matthew J. Ryan Veterinary Hospital with newly diagnosed non-Hodgkin's lymphoma to receive the experimental vaccine following standard induction chemotherapy and confirmation of clinical remission. The goal of the study was to determine whether the vaccine would prevent or prolong time to a relapse, a common scenario in both humans and dogs with NHL.

"We vaccinated dogs, which were in clinical remission following chemotherapy, three times," Mason said. "We then tracked them over several years to see if the vaccine would prevent relapse and would prolong overall survival.

"We found that, although the vaccinated dogs still relapsed with clinical disease when they were treated with rescue chemotherapy, they had significantly increased overall survival times when compared to an unvaccinated control group. Some of these dogs are still alive and cancer free more than three years later.

"The results with these dogs indicate that our immunotherapy and rescue chemotherapy appear to act synergistically to prevent a second relapse -- a phenomenon that has been previously recognized in human patients treated with other types of immunotherapy," she said.