Cancer vaccine shows promise against HPV-related throat tumors in early study

A lab study in mice and in human tumor samples found a therapeutic HPV vaccine built with spherical nucleic acids slowed tumor growth and boosted T-cell responses; human clinical testing is still required.

Scientists report a therapeutic vaccine designed for HPV-driven head and neck cancers produced strong immune responses in laboratory tests. The vaccine is built from spherical nucleic acids (SNAs) that carry a fragment of an HPV tumor protein alongside an adjuvant to stimulate immune cells. In mice the vaccine slowed tumor growth and improved survival, and in human tumor samples it increased cancer-cell killing compared with other vaccine arrangements. The researchers note these are preclinical findings and that outcomes in animals and isolated tissues do not always predict results in people. Key findings: - A vaccine design that attached the HPV fragment to the surface of the SNA at the fragment's N terminus triggered the strongest immune response, causing killer T cells to produce up to eight times more interferon-gamma. - In mouse models the vaccine significantly slowed tumor growth and improved survival, and in tumor samples from patients the N-terminus design killed two to three times more cancer cells than the alternative designs. - Investigators report the improved effect came from changing the arrangement of the same components rather than adding new ingredients or increasing dose, and they indicate clinical testing in people is the next step; timing is undetermined. Summary: The study highlights that the geometry and placement of vaccine components can substantially change immune activation in preclinical HPV-positive tumor models. Whether this design will be safe and effective in people remains to be determined through clinical testing; timing is undetermined.