Last month the U.S. Department of Agriculture (USDA) approved Oncept, a new canine melanoma vaccine that will help extend the lives of dogs with oral melanoma.
“The approval of Oncept is a milestone in the cancer vaccine field and a significant advancement for our DNA delivery technology platform,” said Vijay B. Samant in a press release. Samant is president and chief executive officer of Vical Inc., the company that developed the vaccine. “Oncept is to our knowledge the only therapeutic vaccine approved, and we believe this achievement is a major step toward the initial approvals of therapeutic vaccines for humans.”
Melanoma is a common cancer in dogs. While it is the most common malignant mouth tumor, it can also occur in a dog’s eye, nail, or paw pad. This type of cancer can affect any breed and is very aggressive. It is usually treated using surgery and/or radiation; it is resistant to chemotherapy. Even if the cancer is successfully removed locally, it frequently spreads through a dog’s body to the lymph nodes, liver, lungs and kidneys.
Because it is difficult for a pet owner to look inside a dog’s mouth, most oral tumors are not detected in their early stages. By the time they are diagnosed, the dog has a poorer chance of recovery. However, these types of tumors are easy for your veterinarian to see during routine oral examinations. You may also be more likely to see them yourself if you brush your dog’s teeth.
If your dog has any of the following symptoms, you should have him checked by your vet:
Difficulty swallowing
Bad breath
Oral bleeding
Loss of teeth
Facial swelling
Oral melanoma is diagnosed by performing a biopsy of the tumor by removing a small tissue sample and sending it to a laboratory for analysis. Your veterinarian also may use x-rays or other diagnostic tools.
While the Oncept vaccine will not prevent oral melanoma, it will help extend the survival of dogs in stage II or III. The vaccine is DNA based, which according to petcancervaccine.com means it uses information found in DNA “to help the dog’s immune system recognize a specific protein found on cells that may normally be ignored, such as melanoma tumor cells.”
According to Vical, the Oncept vaccine contains a gene that encodes tyrosinase, a human enzyme that is associated with skin pigmentation. The human tyrosinase used in the vaccine is similar to the dog enzyme, and it stimulates an immune response against canine melanoma cells producing the enzyme. Because the enzyme in the vaccine is from a non-canine species, it makes dogs produce tyrosinase that is considered foreign by their immune systems, thus stimulating a strong immune response. Because the human tyrosinase is similar to canine tyrosinase, the dog’s immune response will target canine melanoma cells.
The vaccine will be manufactured by Merial, which makes several canine vaccines as well as Frontline flea and tick control products.
PHOTOS: veterinarymedicine.dvm360.com, petinsurance.com,organic-pet-digest.com