Can A New Adoptive Cell Immunotherapy Induce Long-term Remission in Dogs with Osteosarcoma?

Key Points

  • A new cancer treatment based on immunotherapy developed by ELIAS Animal Health is currently available for osteosarcoma patients.

  • In the clinical trial, half of the ten dogs that completed the therapy became disease-free and experienced long-term remission.

  • The treatment includes vaccination and T-cell infusion, and is a form of vaccine-primed adoptive cell therapy.

Wouldn't it be wonderful if remission from canine osteosarcoma meant years of ball-chasing, tail-wagging and living a dog's best life?


Osteosarcoma is one of the most aggressive type of canine cancer. Even with amputation and chemotherapy, the survival time is typically less than a year. Having lost our dog, Gus, to osteosarcoma three years ago, I've been particularly interested in research for new treatments for this disease.


Like many dogs, Gus ended up with pulmonary metastasis 12 months after his diagnosis, and my big disappointment was not being able to enroll him in a immunotherapy clinical trial for a shot at a long-term remission.


Immunotherapy engages the immune system to fight cancer and has produced outstanding results in some human patients.

Dog with osteosarcoma after amputation surgery
Gus was happy and active after his amputation. Sadly, he didn't have a chance at an immunotherapy treatment and passed away a little over 12 months after diagnosis.

After losing Gus, I wanted to learn as much as possible about research in dog cancer treatments. So in early 2018, I flew to Anchorage, Alaska, to attend a Veterinary Cancer Society conference, which is where I first learned about a new immunotherapy developed by ELIAS Animal Health and began following their work.


Recently, they reported findings from their clinical trial so I reached out to their founder and CEO Tammie Wahaus, and their Chief Medical Officer Noel Reyes DVM to learn more. I also had a conversation with Prof. Jeffrey N Bryan DVM Ph.D., who led their clinical studies at the University of Missouri.


Here is a summary of what I learned.

Tammie Wahaus, CEO of ELIAS Animal Health
Tammie Wahaus, CEO of ELIAS Animal Health

What is ELIAS Cancer Immunotherapy or ECI®?


Elias Cancer Immunotherapy or ECI is a form of immunotherapy known as Autologous Adoptive Cell Therapy or Adoptive T-Cell Therapy.


A dog's cancer-fighting T-cells are removed and activated in the laboratory and infused back into the dog so they can better kill cancer cells.


ELIAS combines it with vaccination. They produce a vaccine using the dog's own tumor cells, so the immune system is first stimulated to recognize the unique proteins on the surface of the tumor cells.

A form of Adoptive Cell Therapy called CAR-T therapy has met with spectacular successes with some human patients with blood cancer.


How does it work?


ECI treatment is administered over 6-8 weeks and consists of two steps.

ELIAS immunotherapy treatment steps
ELIAS Immunotherapy Treatment Steps

Step 1


The patient dog undergoes amputation surgery of the affected limb. A tumor sample is sent to ELIAS's lab, where a vaccine is created. This patient-specific vaccine is injected intradermally weekly for three weeks.

The goal of this step is to increase the number of primed T-cells that specifically target cancer neoantigens in the patient's body. (Neoantigens are new antigens or proteins formed by cancer-specific mutations and found on the surface of tumor cells).


Step 2


The white blood cells are removed from the patient in a procedure called apheresis. It takes 4-6 hours depending on the size of the dog and requires sedation.


The collected white blood cells are sent to ELIAS's lab.


In the lab, mononuclear white blood cells are stimulated using a T cell-specific super-antigen. The vaccine-primed precursor T-cells are differentiated and activated into effector T-cells that can attack cancer.


These activated T-cells are shipped back to the clinic where, roughly seven days after apheresis, the patient receives an infusion of the T-cells.


The dog also receives five subcutaneous IL-2 injections. IL2 is an immune-stimulating cytokine (molecules usually secreted by cells) and helps sustain in-vivo T-cell proliferation.


What do we know about the safety of the treatment?


ELIAS has been evaluating ECI for several years by working with different veterinary teaching hospitals and clinicians.


In a trial recently described in a scientific conference paper, a total of 14 dogs with osteosarcoma were enrolled and evaluated.


The dogs included lab retrievers, few golden retrievers, and Great Danes. The median age was 6.6 years old, and the median weight was 39 kg (85lb).


Ten out of fourteen dogs completed the entire treatment protocol.


For all dogs, the treatment proved to be very safe and the observed side effects were mild to moderate and transient.


What is the standard-of-care treatment for dogs with osteosarcoma and does this immunotherapy treatment extend survival times?


Standard-of-care treatment for many osteosarcoma patients consists of amputation surgery followed by chemotherapy. And ECI’s median survival time was greater than historical survival times for dogs receiving surgery and chemotherapy treatment.


The median survival time for dogs getting surgery (without chemotherapy) is 134 days.

The median survival time for dogs receiving surgery+chemotherapy is 308 days.


ELIAS reported a median survival time of 415 days for dogs who had surgery + ECI. (No chemotherapy)


This means that half the dogs who finished their treatment survived beyond 415 days.


The survival times and quality of life have been impressive for some dogs, according to ELIAS.

Table comparing median survival times for dogs who received immunotherapy vs amputation vs amputation plus chemotherapy
Comparison of Median Survival Times (source: TVAX)

However, we have to remember that n is still very small in their trial.


So their findings do not mean that roughly half of the dogs receiving the treatment are guaranteed to experience long-term remission.


A larger clinical trial is being planned, so they can better understand the efficacy and safety of the treatment.

Kaplan Meier survival curve for dogs receiving adoptive cell transfer immunotherapy
Kaplan Meier survival curve (10 dogs) source: ELIAS

What do we know about how different dogs responded to the treatment?


Five of the ten dogs that completed the treatment were still alive and disease-free at the time of the conference paper at the end of 2019.