Calviri, Inc. announced the successful conclusion of the Vaccine Against Canine Cancer Study (VACCS) on May 4, 2024; a five-year clinical trial investigating a novel preventative cancer vaccine in dogs. This multi-center, double-blind, placebo-controlled study, the largest of its kind in veterinary oncology, represents a significant milestone in the fight against canine cancer.
Revolutionizing Canine Cancer Prevention: A Paradigm Shift
On the road to end cancer.
For many years, attempts at developing cancer vaccines have been unsuccessful. However, the realization of the importance of neoantigens for generating immune responses against tumors has led to recent reports of successful vaccines in humans. Neoantigens are irregular peptides from mutations in tumor DNA. Unfortunately, these mutations are unique to each patient, requiring personal vaccines.
The VACCS trial marks a paradigm shift by leveraging what we now know are shared neoantigens. Stephen Albert Johnston, CEO of Calviri and former Professor at Arizona State University, discovered these unique protein fragments that arise from errors during tumor RNA processing, and that they are present across multiple cancer types. The VACCS vaccine consisted of 31 of these shared neoantigens, allowing for a broad-spectrum approach to cancer prevention. This strategy has the potential to revolutionize canine cancer prevention by offering a single vaccine to protect against a wide range of cancers and may provide critical proof-of-concept to initiate similar efforts for human cancer prevention. The rationale for testing a preventative cancer vaccine in dogs was published (A Worldwide Preventative Cancer Vaccine Is Achievable With New Discoveries And Comparative Oncology (gavinpublishers.com))
Collaborative Research and Rigorous Design: Ensuring Scientific Merit
The VACCS trial was conducted at three U.S. academic institutions renowned for their expertise in veterinary oncology: Colorado State University, University of Wisconsin-Madison, and University of California, Davis. Over 800 dogs were enrolled in the trial, following a meticulous screening process to exclude any pre-existing tumors or other serious health issues. Participants were then randomly assigned to receive either the investigational vaccine or a placebo, ensuring scientific rigor and unbiased results. Subsequently, dogs were examined every 6 months for tumors and received a vaccine boost ever year. Blood samples were collected to examine dogs’ health and immune response to the vaccine. The trial design has been published (Design of a randomized, placebo-controlled study evaluating efficacy and safety of a cancer preventative vaccine in dogs – ScienceDirect).
Safety remained a top priority throughout the trial, with an independent Data Safety Monitoring Board headed by Dr. Kristen Weishaar closely overseeing the process. Fortunately, no significant vaccine-related adverse events were reported.
Promising Outcomes and Future Developments: A Brighter Future for Canine Health
While the analysis of the trial’s primary efficacy data, specifically the impact on cancer incidence, is still ongoing and slated for publication in a peer-reviewed journal, the initial safety/efficacy profile is highly encouraging. Based on these positive findings, Johnston, stated that “The safety and efficacy results are encouraging enough that we have begun production of an improved version of the vaccine for approval and conditional sales.” This next-generation vaccine holds the promise of becoming a valuable tool in the fight against canine cancer.
Gratitude for Collaboration and Owner Participation: Recognizing the Importance of Teamwork
The success of the VACCS trial hinged on the invaluable collaboration of the participating institutions and the remarkable commitment of dog owners.
According to Dr. Douglas Thamm, principal clinical investigator (CSU), “The owner participation was amazing. This was one of the largest clinical trials for dogs and it required significant commitment on the part of the owners. The owners made the trial a success.”
“The motivation of many of the dog owners was that this trial would lead to developing a vaccine to prevent cancer in humans. We all hope they are right” stated Dr. Jenna Burton, co-PI at CSU.
Calviri extends its sincere gratitude to Open Philanthropy for their critical grant funding, which enabled this high-risk, potentially transformative research endeavor. “We are grateful that OP would take a chance, where no one else would, to fund such a high-risk trial” said Dr. David Vail, PI, UW.
“The VACCs team has done an amazing job” said Heather Youngs, Senior Program Officer at Open Philanthropy. “We are so pleased with the progress on this trial and the potential of this technology to save many animal (and potentially human) lives in the future.”
The unwavering support of these partners was instrumental in bringing this groundbreaking research to fruition.
The VACCS trial stands as a significant advancement in the field of canine cancer prevention. The veterinary community and dog owners will eagerly await the forthcoming publication of efficacy results. This trial has the potential to pave the way for a future where canine cancer is not a constant threat, but a preventable disease.
Calviri is also developing a diagnostic for the early detection of cancer in dogs and people, as well as off the shelf therapeutic and preventative cancer vaccines. Calviri is a spin-out of ASU and headquartered in the Phoenix Bioscience Core.