EGFR/HER2 Yale Vaccine Update

Posted by Pam Hidaka:

Last Tuesday I joined a live Zoom webinar hosted by Canine Cancer Alliance featuring Professor Mark Mamula, an immunologist at Yale School of Medicine, Department of Internal Medicine/Rheumatology and Yale Cancer Center, and founder of TheraJan LLC. The topic was the Canine EGFR/HER2 Peptide Cancer Immunotherapy, also known as the Yale vaccine, now in clinical trials across the country. 100+ people joined the webinar, which was about 2 hours of information plus many questions by participants.

Canine Cancer Alliance has directly funded Mamula’s work at Yale and the clinical trials since 2019. This webinar was a very good and encouraging opportunity to hear about a promising cancer therapy.

Prof. Mamula is a Golden Retriever owner who lost one of his dogs to inoperable cardiac hemangiosarcoma 11 years ago. He realized the dearth of cancer treatments and information for owners, which perked his interest in the field. “Dogs, just like humans, suffer greatly from their cancers," he said. "If we can provide some benefit, some relief, a pain-free life, that is the best outcome we could ever have.”

The cancer statistics aren’t encouraging, he says. There are 90 million dogs in the U.S. which is more dogs than kids under age 18. 1 in 4 dogs will get a cancer in their lifetime, and dogs fortunate enough to reach 8-10 years, 1 in 2 dogs will get a cancer.

Canine cancers have more rapid growth than human cancers, but otherwise are identical. The EGFR/HER2 family of cancers are associated with poor prognosis, tumor growth and metastasis. These include osteosarcoma, hemangiosarcoma, transitional cell/bladder cancer, as well as cancers of the anal sac, squamous cell, thyroid, non-small cell lung, soft tissue sarcoma, breast and colon. Osteosarcoma, hemangiosrcoma and transition cell/bladder cancer are the main focus of the current clinical trial.

In an early case study, a dog with osteosarcoma failed conventional chemo, and had metastasis to the lungs. 8 months post treatment with the Yale vaccine, the lung lesion resolved and the dog survived 3.5 more years. With amputation and chemo, 30-40% of these dogs will survive 12 months, but adding EGFR/HER2 therapy doubles this survival time, and there are a number of multi-year survivors of 5-6 years.

Adding EGFR /Her2 Yale vaccine therapy for Hemangiosarcoma stages I, II & III significantly increased survival, and doubled the mean survival, which is 1 year with conventional therapy alone, particularly for stages I & II. Stage II (invasion of cancer outside the primary site) improved survival over 200 days, with case studies of 2 years or more. EGFR/HER2 therapy, when used BEFORE surgical intervention also improves outcomes.

Gilvetmab by Merck (currently available, mainly for mast cell, but oncologists can order it for their selected use) is the first PD1 Checkpoint dog cancer inhibitor. The Seattle-area clinical trial at Bridge Animal Referral Center uses Gilvetmab in combination with carboplatin and the Yale vaccine. Mamula reiterated several times in the webinar that combination therapy (radiation, chemo, surgery Gilvetmab, EGFR immunotherapy etc) as with humans, is most effective, improving outcomes than when therapies are used alone.

Incidentally, Mamula also cited a study at Washington State University on palliative radiation used with the Yale vaccine which is a good option for dogs with osteosarcoma who cannot have amputation.

Clinical trials are on-going through the country, and are approved through the end of 2026. By then, Mamula thinks their USDA application for licensing will be active. In 2024 the Yale vaccine had been given to 300 dogs – by December 2025 that number increased to 600, with good results, and they have a lot of data to analyze as to if there are effective differences in breeds, ages etc. There is no data on preventative use of the Yale vaccine.

As to side effects, local injection site inflammation was seen in 20% of dogs, but no appetite or energy changes.

Mamula expects their data to be published in a month.

He listed some key points:

• See your veterinary oncologist for the best options for cancer care

• Combination therapy tends to be a good (or better) option compared to single therapies.

• Just as in human cancer care, not all cancers respond to the same therapy – tumors are ‘smart’

  
  

Mark Mamula thanks all the owners who don’t accept the usual standard of care and want to do better for their dog and have participated in the clinical trial. He’s gratified to hear from patients who are still doing well 5 years post-diagnosis. Many webinar participants gave testimonials to their dogs current good health status after having the Yale vaccine and boosters. That was so encouraging to hear!

Get Your Free Immunotherapy Guide

---

Check out other articles and videos

• Could This Combination Immunotherapy Help Dogs Beat Osteosarcoma (and other aggressive cancers)?

• Finding better, less toxic cancer treatments for dogs with a new genomic test?

• A New Promising Combination Immunotherapy Trial: Autologous Cancer Vaccine with Immune Checkpoint Inhibitor (K9-ACV + ICI)

Questions? Email us at info@ccralliance, and we'll get back to you as soon as we can!

Canine Cancer Alliance is a non-profit organization supporting research for canine cancer cures.

All information on the Canine Cancer Alliance website is for educational purposes only. It is not intended to be a substitute for professional veterinary advice.

Always seek guidance from your veterinarian with any questions regarding your pet’s health and medical condition.