Why Cancer Vaccines' Greatest Advantage May Be Durability of Response, Not Immediate Tumor Shrinkage

Keith L. Knutson, PhD, Professor of Immunology, Mayo Clinic, and Eric von Hofe, PhD, CEO, CellxLife, discuss the evolution of personalized cancer vaccine development in an interview with BioPharm International®. They also explain why individualized tumor characterization has become central to generating an effective immune response. In June 2026, the two organizations entered into a licensing agreement centered around a dendritic cell vaccine in clinical development for ovarian cancer.¹

Dr Knutson emphasizes that decades of research have shown that individual tumors differ substantially in protein composition and structure, even those originating in the same anatomic location. Early efforts assumed an off-the-shelf vaccine targeting a common biomarker, such as HER2-neu in HER2-positive breast cancer, would be broadly effective, but that approach has proven insufficient, he says, because structural differences between tumors can block immune system access and recognition.

"This started to become clear that we needed to be able to evaluate the tumor at the individual level and design vaccines based on what we see in an individual's tumor," Dr Knutson explains.

Why do cancer vaccines offer durability advantages that other cancer therapies lack?

Dr von Hofe adds that cancer vaccines have demonstrated an excellent safety profile with minimal associated toxicity, positioning them well for use after initial standard-of-care treatment. Early cancer vaccine research established that an immune response against tumors could be generated, he notes, but translating that response into extended overall survival and relapse-free survival proved more difficult.

"The big difference is the durability of response," Dr von Hofe states, contrasting cancer vaccines with chemotherapy and other therapeutics that typically produce an immediate but not durable improvement in survival.

Dr Von Hofe also notes that cancer recurrence, rather than the initial tumor, remains the central clinical challenge in cancer care, and, today, said cancer vaccines are beginning to show real promise in preventing that recurrence across a growing number of cancer types.

About the speakers

Keith L. Knutson, PhD, Professor of Immunology, Mayo Clinic

Dr Knutson is a consultant in the Department of Immunology, Mayo Clinic in Florida, with a joint appointment in the Department of Cancer Biology.He serves as the director of the Mayo Clinic in Florida Cell Analysis and Cell Imaging Core.He is also co-director of the Mayo Clinic Enterprise Cancer Center’s Cancer Immunology and Immunotherapy Program and vice chair of the Mayo Clinic Enterprise Research Personnel Committee.Dr. Knutson joined the staff of Mayo Clinic in 2005 andholds the academic rank of Professor of Immunology, Mayo Clinic College of Medicine and Science. He is recognized with the distinction of the Andrew A. and Mary S. Sugg Professor of Cancer Research. He received his Bachelor of Science in Microbiology at the University of Washington and earned his PhD in Physiology and Pharmacology from the University of Georgia.

Eric von Hofe, PhD, CEO, CellxLife

Dr Hofe has more than 30 years of experience in managing and overseeing novel biotechnology approaches to cancer immunotherapy and technology development. Prior to becoming CEO of CellxLIfe, he led development efforts at AffyImmune Therapeutics raising over $20 million and advancing a novel CAR T cell therapeutic into the clinic against refractory thyroid cancer. Previously he led the development of an immunotherapeutic vaccine for breast and prostate cancer at Antigen Express, resulting in a collaboration with Merck. Prior to that he held positions at Millennium Pharmaceuticals overseeing the advancement of internal technology development projects and personalized medicine.

Reference

1. CellxLife. Cellxlife enters into exclusive license agreement for dendritic cell vaccine for ovarian cancer. Published June 16, 2026. Accessed August 13, 2026. https://www.cellxlife.com/