Treatment of Canine Metastatic Osteosarcoma with Combined Tumor Microenvironment Modification and Allogeneic Vaccination

The purpose of this study is to evaluate the combination of a new tumor vaccine given in combination with an oral therapy designed to stimulate the immune system in dogs with malignant bone cancer (osteosarcoma) that has spread to the lungs after amputation and chemotherapy. Unfortuantely, osteosarcoma that has spread to the lungs is very resistant to therapy; only 10% of dogs have their tumors shrink in response to a variety of treatments and the survival time after diagnosis of spread is only 2-3 months. We recently showed that an oral treatment consisting of 3 drugs was able to shrink osteosarcoma spread to the lungs in 30% of dogs. Also, another 40% of dogs had their tumors stabilize, improving the survival time to 150 days. These drugs work by changing the immune cells that are present in the tumor from those that prevent or suppress an effective immune response, to those that help support an immune response against the tumor (i.e., help to kill the osteosarcoma cells). The 3 drugs are: 1) Toceranib (Palladia), a drug that is approved to treat cancer in dogs. Toceranib has been shown to decrease two types of immune cells that actively block activation of other immune cells against the cancer. 2) Losartan, a blood pressure medication that has been shown block also help regulate the flow of immune cells into the tumor. 3) Ladarixin, a drug that blocks a key receptor (IL-8 receptor) immune cells use to help block the action of other immune cells. In the current study, we will combine this 3-drug oral therapy with a vaccine that is designed to further stimulate an immune response against the osteosarcoma cells in dogs that have spread of the cancer to their lung.

Your dog will need to have had a diagnosis of osteosarcoma and have undergone amputation and chemotherapy prior to the development of tumor spread to the lungs to be eligible for the study. Additionally, your dog must be free of other conditions (liver, kidney, heart disease) and must be feeling relatively good to be eligible to enroll in the study.

Exclusion Criteria

Significant liver, kidney or heart disease

Client Benefits

The study will provide the oral drugs and tumor vaccines for free, and will cover nealy all the costs of the study (office visits, x-rays, bloodwork), with the exception of bloodwork at weeks 4, 12, and 20 (approximately $250 per visit) and some oral medications that may be used to treat side effects (i.e., imodium for diarrhe, anti-nausea medication, pepcid for stomach protection). The study will not cover costs associated with conditions unrelated to the osteosarcoma treatment (skin infection, ear infection, etc.).

Sample or Data Requirements

At each study visit, blood will be collected (approximately 2.5 tablespoons) to make sure that the treatment is not affecting your dog’s normal body functions (blood counts, liver, kidneys). This blood will also be used to measure activation of your dog’s immune system and response to the tumor vaccine. X-rays of the lungs will be taken prior to starting the study and then again at 8, 16 and 24 weeks. If your dog is doing well, a final vaccine booster will be given at 24 weeks.

Contact Info

For questions regarding the clinical trial, please email Clinicaltrials@tufts.edu.