Practical Use of Tigilanol Tiglate for Treatment of Mast Cell Tumors in Dogs

In the Literature

Musser ML, Jones PD, Goodson TL, Roof E, Johannes CM. Response to tigilanol tiglate in dogs with mast cell tumors. J Vet Intern Med. 2024;38(6):3162-3169. doi:10.1111/jvim.17211

The Research …

Tigilanol tiglate is a novel therapy FDA-approved for intratumoral injection of nonmetastatic cutaneous and subcutaneous mast cell tumors (MCT) located at or distal to the elbow or hock in dogs.^1-4

This study^a was designed to characterize use of tigilanol tiglate in veterinary oncology and examine the clinical response rate. Data from 149 dogs with 151 treated tumors, including patients previously treated with other therapies (eg, radiation, surgery, chemotherapy, immunotherapy, electrochemotherapy), were included. Patients receiving additional therapies concurrently with tigilanol tiglate and patients with multiple MCTs treated simultaneously were excluded. Concurrent administration of medications (eg, prednisone, H₁- or H₂-receptor antagonists, antiemetics, antidiarrheals) was allowed.

Crossbreeds, pit bull terriers, Labrador retrievers, and boxers were most common. Most tumors (67%) were on a limb, although trunk, muzzle, mucocutaneous junction, and other locations were also reported. Most patients (81%) had no pretreatment with other therapies prior to tigilanol tiglate injection. Sedation was required for 57% of tigilanol tiglate injections, and general anesthesia was required for 2%. The median longest tumor diameter treated was 1.7 cm.

Complete resolution was achieved in 75% of tumors following a single tigilanol tiglate injection, and 68% of tumors given a second injection achieved complete resolution. Wounds reported secondary to tigilanol tiglate injection had a median area of 4.71 cm². Largest wound formation occurred in a median of 7 days, and complete healing occurred in a median of 30 days. A durable response to a single treatment with tigilanol tiglate 1 year after treatment was reported in 64% of patients with follow-up data.

^a Development of the REDCap survey used to collect information for this study was financially supported by QBiotics.

… The Takeaways

Key pearls to put into practice:

• Tigilanol tiglate is an effective novel therapy for MCT in dogs and can be used alone or following other treatment modalities like radiation and surgery, although the latter-mentioned therapies remain the standard of care.

• Sedation is recommended with tigilanol tiglate injection to minimize potential injection pain and risk for infiltration of the drug into surrounding tissues. Veterinary team members should be aware of the potential for significant tissue damage from a needlestick injury when drawing up and administering this drug.

• Dogs with nonmetastatic tumors <2 cm in diameter at or below the hock or elbow are ideal candidates for treatment with tigilanol tiglate. The minimum dose per tumor is 0.1 mL; total dose should not exceed 5 mL/dog.^1-4 To reduce the risk for potentially life-threatening effects of MCT degranulation, oral H₁- and H₂-receptor antagonists should be administered on the day of and for 7 days following treatment, and corticosteroid therapy should be administered 2 days prior to and for 8 days following treatment.^1-4

• Most MCTs respond to a single injection of tigilanol tiglate and maintain a clinical response 1 year after treatment. If the first injection does not induce remission, a second injection results in complete regression in most patients. Proper case selection is essential, as wound formation with injection is common. Wounds typically develop within 7 days after treatment and resolve within 1 month with supportive care.