He is optimistic, however, that it will also work for humans.
"I decided to use dogs because vets use chemotherapy and radiation therapy in much the same way as humans with cancer are treated."
Although the science is complicated and groundbreaking, the treatment is simple. The dogs need only two shots three weeks apart.
So far, everything is going well. The vaccines not only slow the growth of the original tumour but also help prevent new ones from developing.
Most dogs in Dr Weir's trial have outlived their vet's expectations and many owners report an improved quality of life.
Sally was lucky. Not only is she a deeply loved family pet, but one of her owners works with Dr Weir and another is a final-year veterinary science student.
She was diagnosed with liver cancer two and a half years ago but was considered too old for chemotherapy.
Her vet did a fantastic job but could not remove the whole tumour because it was too close to a blood vessel, says owner Jenny Millar.
He kept a bit of the tumour, which Dr Weir used to make a vaccine.
"As soon as she recovered from the surgery I took her to the laboratory. My mother brought down the vaccine and I gave her an injection in the car park.
"We did not expect her to make it this long. She's wonderful. She's doing well. We have to stop her from running about too much.
"It is great that this is potentially going to help people in the future."
Royal North Shore Hospital medical oncologist Professor Stephen Clarke says the vaccine has been shown to be both safe and effective in animals.
This "bodes well" for the start of clinical trials in the near future.
"It's essential to undertake animal studies before starting studies in cancer patients and these results are very encouraging."
- AAP