Cationic nanogel–based nasal therapeutic HPV vaccine prevents the development of cervical cancer

Therapeutic vaccines against cervical cancer caused by human papillomavirus (HPV) are still an unmet medical need, despite a prophylactic HPV vaccine being available, and the now-licensed systemic vaccines may have a limited effect on the reproductive tract. To specifically inhibit cervical cancer development, the concept of mucosal immunity based on the reproductive-respiratory axis was adopted to develop a nasal HPV therapeutic vaccine. We used a cationic nanogel for the nasal vaccine delivery system and targeted HPV16 E7, an oncoprotein in HPV-driven cervical cancer to demonstrate the feasibility of a nasal therapeutic vaccine. The vaccine was combined with cyclic di-adenosine monophosphate as a cell-mediated immunity-inducing adjuvant. Intranasal immunization with the nanogel vaccine induced E7-specific CD4⁺ and CD8⁺ T cells in mouse cervicovaginal tissue. An antitumor effect due to the infiltration of vaccine-induced E7-specific T cells was also observed in an orthotopic tumor model in mice. Furthermore, intranasal immunization of nonhuman primates with the nanogel vaccine using a spray device that is also applicable to humans induced E7-specific T cells in the reproductive tissues. Our findings demonstrated that this nasal therapeutic vaccine effectively controlled cervical cancer and will contribute to preclinical evidence for clinical testing in the near future.