Palladia for Dogs (toceranib phosphate)

What Is Palladia?

Toceranib phosphate is an oral tablet that has received FDA approval as an antineoplastic agent for dogs.¹ It was approved for treating grade II and grade III mast cell tumors, with or without evidence of spread to the lymph nodes.² At one point considered only for use in those intermediate and high-grade mast cell tumors, Palladia for dogs is now a common cancer strategy for many types of cancer.

Additional veterinary studies have found additional promising uses for this medication.² Toceranib phosphate was developed as a veterinary product, unlike many cancer treatments which were originally approved for use in humans. ²

Brand Names

Palladia^® is the brand name of Toceranib phosphate.

How Palladia Works

Palladia inhibits (stops or slows down) the activity of the enzyme tyrosine kinase.

By doing so it limits the growth of tumors, decreases the recruitment of new blood vessels to tumors (anti-angiogenesis), and limits the spread of tumor cells (metastasis).²

Common Uses for Palladia

Although toceranib phosphate was initially approved to treat mast cell tumors in dogs, it is showing promise for other cancers as well.

Mast Cell Tumors

Toceranib phosphate is approved for use in treating grade II or III mast cell neoplasia with or without regional spread to lymph nodes. ^1,2

Heart Base Tumors

A 2019 study retrospectively evaluated the use of toceranib phosphate in 28 dogs with heart base tumors. The study noted a 10% response rate, and 90% of the dogs showed improvement of clinical signs after starting treatment. That means that 10% went into remission, and 90% showed signs of improvement in symptoms. For 81% of dogs, the symptoms completely resolved.³

Gastrointestinal Stromal Tumors

A small retrospective study of seven dogs with gastrointestinal stromal tumors reported that 71% demonstrated benefit from toceranib therapy.⁴

Pheochromocytoma

In a small 2018 study, five dogs received Palladia for a pheochromocytoma. One demonstrated a partial response and the remaining four had stable disease for 11-36 weeks.⁵

Assorted Solid Tumors

A 2012 study assessed the use of Palladia in 85 dogs diagnosed with apocrine gland anal sac adenocarcinoma, head and neck carcinoma, metastatic osteosarcoma, nasal carcinoma, and thyroid carcinoma.

Nearly three quarters (74%) of the dogs studied demonstrated a clinical benefit of either partial response (tumors shrinking), stable disease (tumors remaining the same, not getting bigger), or complete response (tumors going away).

This was an initial study, so more research is needed.⁶

Safety and Side Effects of Palladia for Dogs

Most common side effects that dogs experience while taking Palladia are:^1,2

• Diarrhea or bloody stool
• Decreased appetite
• Vomiting
• Lethargy
• Lameness
• Weight loss
• Pigment changes

Side effects can range from mild to severe. If your dog experiences side effects from toceranib phosphate, call your veterinarian or oncologist to determine if your dog should continue therapy or not. Decreasing the dose may help to resolve side effects.

When to Not Use Palladia

Toceranib phosphate may impair wound healing. Your veterinarian will guide you on how to discontinue use before surgery.²

Do not use in dogs used for breeding or pregnant or lactating dogs.¹

The following medications either have been reported to adversely interact with toceranib or may have adverse reactions in dogs. This does not mean that they cannot be used together, however, you should consult with your veterinarian regarding the use of toceranib with these medications:²

• Calcitriol
• Non-steroidal anti-inflammatory drugs (NSAIDs)
• CYP3AQ4 inhibitors (clarithromycin, fluconazole, grapefruit juice, itraconazole, ketoconazole, verapamil)
• Other chemotherapeutic drugs

How to Give Palladia

Palladia is generally dosed orally on every other day or every third day schedules.²

Weekly veterinary monitoring is recommended for the first six weeks and then every six weeks afterwards.^1,2 Your veterinarian will monitor your dog’s:

• red blood cell count
• white blood cell count
• kidney function
• phosphorous levels
• serum protein levels

These tests will regularly monitored. ^1,2 Changes in these laboratory values may influence whether you continue to give this medication.

Gastrointestinal bleed or diarrhea may also be reasons for your veterinarian to discontinue the use of toceranib phosphate. ¹

Do not just stop giving Palladia; discontinuation should always be under the advice of your veterinarian.

Discontinuation may be temporary until the abnormal lab values or gastrointestinal signs resolve, or dosages may be reduced, so your dog has fewer side effects.^1,2

Your veterinarian may also monitor your dog’s blood pressure, thyroid level, full chemistry panel, and urine protein: creatinine ratio.²

What If I Miss a Dose of Palladia?

If a dose is missed, contact your veterinarian and ask for further instructions.

Storage and Handling of Palladia

Even though it is given at home, Palladia is still a chemotherapy drug, and you should take precautions to avoid exposure to it.

• Store at room temperature, out of the reach of children and pets.²
• Wear gloves when handling Palladia or any feces, urine, or vomit from your cancer patient.
• Do not crush or split tablets.²
• Be sure that all soiled laundry is washed separately.²