CVM Canine brain tumor clinical trials

Clinical trials open to dogs with brain tumors 

By Fran Howard

Batman, the first patient to undergo a breakthrough experimental treatment for brain cancer in dogs, has become a poster dog for the revolutionary protocol. The pointy, black ears of the 10-year-old German shepherd mix gave the cancer-surviving superhero his name, but his doctors gave him back his life. Without treatment, Batman was not expected to survive past Halloween 2008. Given the circumstances, one wonders whether Batman’s doctors, John Ohlfest, Ph.D., and G. Elizabeth Pluhar, D.V.M., Ph.D., aren’t the true superheroes.

The University’s dynamic duo developed a combination treatment plan for dogs with glioma, a very aggressive and relatively common form of brain cancer. The treatment, which is now available to other dogs with brain cancer, dramatically extended Batman’s life. The three-pronged treatment approach consists of first surgically removing the tumor, then treating the surgical site with a form of gene therapy to attract immune cells that will recognize and destroy remaining tumor cells, and finally administering an anti-cancer vaccine made from the dog’s own cancer cells to prevent tumor recurrence.

Now nearly a year after Pluhar, a veterinary surgeon at the Veterinary Medical Center, and Ohlfest, head of the neurosurgery gene therapy program at the Masonic Cancer Center, gave Batman his initial treatment, the celebrated dog is still enjoying life. The neurological deficits that led to his diagnosis have been almost eliminated. “We documented an anti-tumor immune response that has correlated to control of the tumor,” says Ohlfest. In other words, the treatment appears to have worked, and the implications could be far-reaching.

“There is the potential for this type of therapy to be used on nearly any type of systemic cancer in dogs, not just brain cancer, because the immune response covers the entire body,” says Pluhar. “I’m hopeful this therapy may in time be used for other types of systemic cancer in dogs.”

Through the help of grants from government agencies and private foundations, Ohlfest and Pluhar have since treated four other dogs for similar tumors. The second dog to receive treatment exhibited an impressive tumor regression following six vaccinations, and Ohlfest and Pluhar are optimistic that the other dogs will show similar responses.
 
Canine brain cancer therapy has been organized within the canine brain tumor clinical trials program. The treatment team already has funding to treat up to 50 dogs. That number could soon exceed 100, though, if additional grants and charitable donations come through.

The area of medicine in which Ohlfest and Pluhar work is called comparative oncology. They use what they learn in veterinary medicine to help humans, and they extrapolate what they can from human medicine to help pet animals. Batman is an excellent case in point.

Ohlfest’s work in gene and immune therapy led to a first generation anti-cancer vaccine to be used in a human clinical trial. However, the early vaccine was expensive and difficult to produce. He subsequently used that vaccine to develop a more potent and less expensive vaccine for dogs.

Now it’s Batman’s turn to return the favor. “I would be very disappointed if we couldn’t write a protocol for humans within a year from what we have learned from our work with dogs,” says Ohlfest. “This is first and foremost a new therapy for dogs, but at the same time, it will be more predictive of what might happen in people than any other form of research.”

The cost of therapy for one dog can range between $10,000 and $20,000. However, dogs with tumors that originate in the brain may be eligible for the canine brain tumor clinical trials program. The program will cover the vast majority of the cost of treatment including surgery and supportive care while the dog remains enrolled in the trial.

Learn more about the trials online at www.cvm.umn.edu. To enroll a dog in a trial, call Kelly Noyes, Small Animal Surgery case manager at 612-624-7441 to schedule an appointment with Dr. Pluhar or visit our Web site at www.cvm.umn.edu. To donate to the research effort, click here and select “new gift” then designate the gift is for the “CVM canine brain tumor clinical trials” effort. Or you can contact Sharon Staton, director of advancement, at 612-624-1247, or e-mail her at stato001@umn.edu.