Experimental cancer vaccine shows promise in animal studies

Consulting for the media

Thursday, November 10, 2022

NIH researchers found that IV administration improves tumor-fighting activity

What

An experimental therapeutic cancer vaccine elicited two distinct and desirable immune system responses that led to significant tumor regression in mice, report researchers at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

The researchers found that intravenous (IV) administration of the vaccine increased the number of cytotoxic T cells capable of infiltrating and attacking tumor cells and engaged the innate immune system by inducing type I interferon. The innate immune response modified the tumor microenvironment, counteracting suppressive forces that would otherwise reduce T-cell activity. Modification of the tumor microenvironment was not observed in mice that received the vaccine by injecting a needle into the skin (subcutaneous administration).

Dubbed “vax-innate” by the scientific team, this approach achieves an important goal in the search for more effective cancer immunotherapy vaccines. The study shows that the IV vaccine enables and enhances T-cell immunity by overcoming tumor-induced immunosuppressive activity. Researchers say the vaccine candidate could be given intravenously to people who have already received tumor-specific T cells as therapy. It could also improve tumor control by increasing the number of T cells and changing the tumor microenvironment so that they function better, the researchers note.

The experimental vaccine, SNAPvax, was developed by Robert Seder, MD, and colleagues at the NIAID Vaccine Research Center (VRC) along with collaborators at Vaccitech North America, a clinical-stage biopharmaceutical company in Baltimore, Maryland. Vaccitech has announced plans to advance the SNAPvax platform for use in the treatment of human papillomavirus-related cancer in 2023.

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