Toceranib (Palladia) is in a new class of drugs currently being used with much success in the treatment of cutaneous mast cell tumors in dogs. Toceranib is useful for treating other tumor types as well, even those tumors that do not respond to chemotherapy. It is orally administered and FDA-approved for use in dogs. Unfortunately, a common side effect is diarrhea which impacts quality of life and requires stopping the drug, waiting a week or more, and restarting at a lower dose. While quality of life is improved at the lower dose, toceranib may not be as effective at the lowered dose.
Cytokeratin 18 (CK18) is a protein expressed in cells that line the gastrointestinal tract. During cell death, CK18 is released into the bloodstream and thus can be measured. Detection of CK18 can be used a marker for damage to the intestinal lining.
The purpose of this pilot study is to determine if plasma CK18 levels can be used as a biomarker to help predict which dogs are at risk for having gastrointestinal side effects.
Dogs will not be eligible if they have serious kidney or liver disease, have been treated with chemotherapy or radiation therapy for their mast cell tumor, have concurrent blood cell changes (like severe anemia), or are currently treated with complementary or alternative medicines. (A 5 day washout period before entry into the study will be sufficient for most medications
Although the study is completed in one month, all of the prescribed toceranib (Palladia) will be provided at no charge to the participating client for 4 months. Toceranib can cost $100 to $450/month depending on patient body weight.